[maven-release-plugin] prepare release ebean-11.15.8

Restore mapping.

README.md

@@ -11,7 +11,7 @@ Goto [https://ebean-orm.github.io/](http://ebean-orm.github.io/ "Ebean ORM's Web
 [Maven central - all related projects](http://search.maven.org/#search%7Cga%7C1%7Cebean "maven central all related projects")
 
 ## Current versions
-* [![Maven Central : ebean](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean/badge.svg)](https://maven-badges.herokuapp.com/maven-central/org.avaje.ebean/ebean) - ebean
-* [![Maven Central : ebean-agent](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-agent/badge.svg)](https://maven-badges.herokuapp.com/maven-central/org.avaje.ebean/ebean-agent) - ebean-agent
-* [![Maven Central : ebean-maven-plugin](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-maven-plugin/badge.svg)](https://maven-badges.herokuapp.com/maven-central/org.avaje.ebean/ebean-maven-plugin) - ebean-maven-plugin
+* [![Maven Central : ebean](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean/badge.svg)](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean) - ebean
+* [![Maven Central : ebean-agent](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-agent/badge.svg)](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-agent) - ebean-agent
+* [![Maven Central : ebean-maven-plugin](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-maven-plugin/badge.svg)](https://maven-badges.herokuapp.com/maven-central/io.ebean/ebean-maven-plugin) - ebean-maven-plugin
 

pom.xml

@@ -9,15 +9,20 @@
 
   <groupId>io.ebean</groupId>
   <artifactId>ebean</artifactId>
-  <version>11.15.1</version>
+  <version>11.15.8</version>
   <packaging>jar</packaging>
 
   <name>ebean</name>
   <url>http://ebean-orm.github.io/</url>
 
+  <properties>
+    <jackson-core.version>2.9.5</jackson-core.version>
+    <snakeyaml.version>1.21</snakeyaml.version>
+  </properties>
+
   <scm>
     <developerConnection>scm:git:git@github.com:ebean-orm/ebean.git</developerConnection>
-    <tag>ebean-11.15.1</tag>
+    <tag>ebean-11.15.8</tag>
   </scm>
 
   <profiles>
@@ -89,7 +94,7 @@
     <dependency>
       <groupId>org.yaml</groupId>
       <artifactId>snakeyaml</artifactId>
-      <version>1.19</version>
+      <version>${snakeyaml.version}</version>
     </dependency>
 
     <!--
@@ -118,7 +123,7 @@
     <dependency>
       <groupId>org.avaje</groupId>
       <artifactId>avaje-datasource</artifactId>
-      <version>3.1.1</version>
+      <version>3.2.2</version>
     </dependency>
 
     <dependency>
@@ -130,7 +135,7 @@
     <dependency>
       <groupId>io.ebean</groupId>
       <artifactId>ebean-migration</artifactId>
-      <version>11.5.1</version>
+      <version>11.5.4</version>
     </dependency>
 
     <dependency>
@@ -143,14 +148,14 @@
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-core</artifactId>
-      <version>2.9.0</version>
+      <version>${jackson-core.version}</version>
     </dependency>
 
     <!-- provided scope for JsonNode support -->
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-databind</artifactId>
-      <version>2.9.0</version>
+      <version>${jackson-core.version}</version>
       <scope>provided</scope>
     </dependency>
 
@@ -169,13 +174,6 @@
       <scope>provided</scope>
     </dependency>
 
-    <dependency>
-      <groupId>javax.servlet</groupId>
-      <artifactId>javax.servlet-api</artifactId>
-      <version>3.1.0</version>
-      <scope>provided</scope>
-    </dependency>
-
     <dependency>
       <groupId>joda-time</groupId>
       <artifactId>joda-time</artifactId>
@@ -224,7 +222,7 @@
     <dependency>
       <groupId>io.ebean</groupId>
       <artifactId>ebean-agent</artifactId>
-      <version>11.10.1</version>
+      <version>11.11.1</version>
       <scope>test</scope>
     </dependency>
 
@@ -254,7 +252,7 @@
     <dependency>
       <groupId>com.microsoft.sqlserver</groupId>
       <artifactId>mssql-jdbc</artifactId>
-      <version>6.1.3.jre8-preview</version>
+      <version>6.4.0.jre8</version>
       <scope>test</scope>
     </dependency>
 
@@ -297,7 +295,7 @@
       <plugin>
         <groupId>io.ebean</groupId>
         <artifactId>ebean-maven-plugin</artifactId>
-        <version>11.10.1</version>
+        <version>11.11.1</version>
         <executions>
           <execution>
             <id>test</id>

src/main/java/io/ebean/EbeanServer.java

@@ -437,6 +437,19 @@ public interface EbeanServer {
    */
   <T> DtoQuery<T> findDto(Class<T> dtoType, String sql);
 
+  /**
+   * Create a named Query for DTO beans.
+   * <p>
+   * DTO beans are just normal bean like classes with public constructor(s) and setters.
+   * They do not need to be registered with Ebean before use.
+   * </p>
+   *
+   * @param dtoType    The type of the DTO bean the rows will be mapped into.
+   * @param namedQuery The name of the query
+   * @param <T>        The type of the DTO bean.
+   */
+  <T> DtoQuery<T> createNamedDtoQuery(Class<T> dtoType, String namedQuery);
+
   /**
    * Create a SqlQuery for executing native sql
    * query statements.
@@ -508,30 +521,44 @@ public interface EbeanServer {
    * etc.
    * </p>
    * <p>
+   * <h3>Using try with resources</h3>
    * <pre>{@code
    *
    *    // start a transaction (stored in a ThreadLocal)
-   *    ebeanServer.beginTransaction();
+   *
+   *    try (Transaction txn = ebeanServer.beginTransaction()) {
+   *
+   * 	    Order order = ebeanServer.find(Order.class,10);
+   * 	    ...
+   * 	    ebeanServer.save(order);
+   *
+   * 	    txn.commit();
+   *    }
+   *
+   * }</pre>
+   * <p>
+   * <h3>Using try finally block</h3>
+   * <pre>{@code
+   *
+   *    // start a transaction (stored in a ThreadLocal)
+   *    Transaction txn = ebeanServer.beginTransaction();
    *    try {
    * 	    Order order = ebeanServer.find(Order.class,10);
    *
    * 	    ebeanServer.save(order);
    *
-   * 	    ebeanServer.commitTransaction();
+   * 	    txn.commit();
    *
    *    } finally {
-   * 	    // rollback if we didn't commit
-   * 	    // i.e. an exception occurred before commitTransaction().
-   * 	    ebeanServer.endTransaction();
+   * 	    txn.end();
    *    }
    *
    * }</pre>
    * <p>
-   * <h3>Transaction options:</h3>
+   * <h3>Transaction options</h3>
    * <pre>{@code
    *
-   *     Transaction txn = ebeanServer.beginTransaction();
-   *     try {
+   *     try (Transaction txn = ebeanServer.beginTransaction()) {
    *       // explicitly turn on/off JDBC batch use
    *       txn.setBatchMode(true);
    *       txn.setBatchSize(50);
@@ -552,10 +579,6 @@ public interface EbeanServer {
    *       ...
    *
    *       txn.commit();
-   *
-   *    } finally {
-   *       // rollback if necessary
-   *       txn.end();
    *    }
    *
    * }</pre>
@@ -585,19 +608,16 @@ public interface EbeanServer {
    * <pre>{@code
    * // Start a new transaction. If there is a current transaction
    * // suspend it until this transaction ends
-   * Transaction txn = server.beginTransaction(TxScope.requiresNew());
-   * try {
+   * try (Transaction txn = server.beginTransaction(TxScope.requiresNew())) {
    *
    *   ...
    *
    *   // commit the transaction
    *   txn.commit();
    *
-   * } finally {
-   *   // end this transaction which:
-   *   //  A) will rollback transaction if it has not been committed already
+   *   // At end this transaction will:
+   *   //  A) will rollback transaction if it has not been committed
    *   //  B) will restore a previously suspended transaction
-   *   txn.end();
    * }
    *
    * }</pre>
@@ -606,20 +626,13 @@ public interface EbeanServer {
    * <pre>{@code
    *
    * // start a new transaction if there is not a current transaction
-   * Transaction txn = server.beginTransaction(TxScope.required());
-   * try {
+   * try (Transaction txn = server.beginTransaction(TxScope.required())) {
    *
    *   ...
    *
    *   // commit the transaction if it was created or
    *   // do nothing if there was already a current transaction
    *   txn.commit();
-   *
-   * } finally {
-   *   // end this transaction which will rollback the transaction
-   *   // if it was created for this try finally scope and has not
-   *   // already been committed
-   *   txn.end();
    * }
    *
    * }</pre>

src/main/java/io/ebean/ExpressionFactory.java

@@ -327,6 +327,30 @@ public interface ExpressionFactory {
    */
   Expression allEq(Map<String, Object> propertyMap);
 
+  /**
+   * Add expression for ANY of the given bit flags to be set.
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  Expression bitwiseAny(String propertyName, long flags);
+
+  /**
+   * Add expression for ALL of the given bit flags to be set.
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  Expression bitwiseAll(String propertyName, long flags);
+
+  /**
+   * Add bitwise AND expression of the given bit flags to compare with the match/mask.
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  Expression bitwiseAnd(String propertyName, long flags, long match);
+
   /**
    * Add raw expression with a single parameter.
    * <p>

src/main/java/io/ebean/ExpressionList.java

@@ -482,7 +482,7 @@ public interface ExpressionList<T> {
 
   /**
    * Extended version for setDistinct in conjunction with "findSingleAttributeList";
-   *
+   * <p>
    * <pre>{@code
    *
    *  List<CountedValue<Order.Status>> orderStatusCount =
@@ -878,7 +878,7 @@ public interface ExpressionList<T> {
 
   /**
    * In - using a subQuery.
-   *
+   * <p>
    * This is exactly the same as in() and provided due to "in" being a Kotlin keyword
    * (and hence to avoid the slightly ugly escaping when using in() in Kotlin)
    */
@@ -888,7 +888,7 @@ public interface ExpressionList<T> {
 
   /**
    * In - property has a value in the array of values.
-   *
+   * <p>
    * This is exactly the same as in() and provided due to "in" being a Kotlin keyword
    * (and hence to avoid the slightly ugly escaping when using in() in Kotlin)
    */
@@ -898,7 +898,7 @@ public interface ExpressionList<T> {
 
   /**
    * In - property has a value in the collection of values.
-   *
+   * <p>
    * This is exactly the same as in() and provided due to "in" being a Kotlin keyword
    * (and hence to avoid the slightly ugly escaping when using in() in Kotlin)
    */
@@ -996,6 +996,53 @@ public interface ExpressionList<T> {
    */
   ExpressionList<T> arrayIsNotEmpty(String propertyName);
 
+  /**
+   * Add expression for ANY of the given bit flags to be set.
+   * <pre>{@code
+   *
+   * where().bitwiseAny("flags", BwFlags.HAS_BULK + BwFlags.HAS_COLOUR)
+   *
+   * }</pre>
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  ExpressionList<T> bitwiseAny(String propertyName, long flags);
+
+  /**
+   * Add expression for ALL of the given bit flags to be set.
+   * <p>
+   * <pre>{@code
+   *
+   * where().bitwiseAll("flags", BwFlags.HAS_BULK + BwFlags.HAS_COLOUR)
+   *
+   * }</pre>
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  ExpressionList<T> bitwiseAll(String propertyName, long flags);
+
+  /**
+   * Add bitwise AND expression of the given bit flags to compare with the match/mask.
+   * <p>
+   * <pre>{@code
+   *
+   * // Flags Bulk + Size = Size
+   * // ... meaning Bulk is not set and Size is set
+   *
+   * long selectedFlags = BwFlags.HAS_BULK + BwFlags.HAS_SIZE;
+   * long mask = BwFlags.HAS_SIZE; // Only Size flag set
+   *
+   * where().bitwiseAnd("flags", selectedFlags, mask)
+   *
+   * }</pre>
+   *
+   * @param propertyName The property that holds the flags value
+   * @param flags        The flags we are looking for
+   */
+  ExpressionList<T> bitwiseAnd(String propertyName, long flags, long match);
+
   /**
    * Add raw expression with a single parameter.
    * <p>

src/main/java/io/ebean/SqlUpdate.java

@@ -30,6 +30,35 @@ package io.ebean;
  * String msg = "There were " + modifiedCount + " rows updated";
  *
  * }</pre>
+ * <p>
+ * <h3>Example: Using setNextParameter()</h3>
+ * <pre>{@code
+ *
+ *  String sql = "insert into audit_log (id, description, modified_description) values (?,?,?)";
+ *  SqlUpdate insert = Ebean.createSqlUpdate(sql);
+ *
+ *  try (Transaction txn = Ebean.beginTransaction()) {
+ *    txn.setBatchMode(true);
+ *
+ *    insert.setNextParameter(10000);
+ *    insert.setNextParameter("hello");
+ *    insert.setNextParameter("rob");
+ *    insert.execute();
+ *
+ *    insert.setNextParameter(10001);
+ *    insert.setNextParameter("goodbye");
+ *    insert.setNextParameter("rob");
+ *    insert.execute();
+ *
+ *    insert.setNextParameter(10002);
+ *    insert.setNextParameter("chow");
+ *    insert.setNextParameter("bob");
+ *    insert.execute();
+ *
+ *    txn.commit();
+ *  }
+ *
+ * }</pre>
  *
  * @see Update
  * @see SqlQuery
@@ -61,7 +90,7 @@ public interface SqlUpdate {
 
   /**
    * Execute and return the generated key. This is effectively a short cut for:
-   *
+   * <p>
    * <pre>{@code
    *
    *   sqlUpdate.execute();
@@ -137,6 +166,13 @@ public interface SqlUpdate {
    */
   SqlUpdate setTimeout(int secs);
 
+  /**
+   * Set the next positioned parameter.
+   *
+   * @param value The value to bind
+   */
+  SqlUpdate setNextParameter(Object value);
+
   /**
    * Set a parameter via its index position.
    */

src/main/java/io/ebean/Transaction.java

@@ -23,6 +23,7 @@ public interface Transaction extends AutoCloseable {
    * This returns the current transaction for the 'default server'.  If you are using
    * multiple EbeanServer's then use {@link EbeanServer#currentTransaction()}.
    * </p>
+   *
    * @see Ebean#currentTransaction()
    * @see EbeanServer#currentTransaction()
    */
@@ -136,6 +137,18 @@ public interface Transaction extends AutoCloseable {
    */
   void rollback(Throwable e) throws PersistenceException;
 
+  /**
+   * Set when we want nested transactions to use Savepoint's.
+   * <p>
+   * This means that for a nested transaction:
+   * <ul>
+   * <li>begin transaction maps to creating a savepoint</li>
+   * <li>commit transaction maps to releasing a savepoint</li>
+   * <li>rollback transaction maps to rollback a savepoint</li>
+   * </ul>
+   */
+  void setNestedUseSavepoint();
+
   /**
    * Mark the transaction for rollback only.
    */
@@ -151,7 +164,6 @@ public interface Transaction extends AutoCloseable {
    */
   void end();
 
-
   /**
    * Synonym for end() to support AutoClosable.
    */
@@ -227,7 +239,7 @@ public interface Transaction extends AutoCloseable {
    * Refer to {@link ServerConfig#setSkipCacheAfterWrite(boolean)} for configuring the default behavior
    * for using the L2 bean cache in transactions spanning multiple query/persist requests.
    * </p>
-   * <p>
+   *
    * <pre>{@code
    *
    *   // assume Customer has L2 bean caching enabled ...
@@ -309,7 +321,7 @@ public interface Transaction extends AutoCloseable {
    * <p>
    * Example: batch processing executing every 3 rows
    * </p>
-   * <p>
+   *
    * <pre>{@code
    *
    * String data = "This is a simple test of the batch processing"

src/main/java/io/ebean/bean/BeanCollection.java

@@ -72,6 +72,11 @@ public interface BeanCollection<E> extends Serializable {
    */
   boolean isSkipSave();
 
+  /**
+   * Return true if the collection holds modifications.
+   */
+  boolean holdsModifications();
+
   /**
    * Return the bean that owns this collection.
    */

src/main/java/io/ebean/bean/EntityBeanIntercept.java

@@ -133,6 +133,20 @@ public final class EntityBeanIntercept implements Serializable {
     this.nodeUsageCollector = usageCollector;
   }
 
+  /**
+   * Return the ownerId (IdClass).
+   */
+  public Object getOwnerId() {
+    return ownerId;
+  }
+
+  /**
+   * Set the ownerId (IdClass).
+   */
+  public void setOwnerId(Object ownerId) {
+    this.ownerId = ownerId;
+  }
+
   /**
    * Return the owning bean for an embedded bean.
    */

src/main/java/io/ebean/common/AbstractBeanCollection.java

@@ -6,7 +6,6 @@ import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
 
-import javax.persistence.PersistenceException;
 import java.util.Set;
 
 /**
@@ -64,7 +63,7 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
     this.ebeanServerName = loader.getName();
     this.ownerBean = ownerBean;
     this.propertyName = propertyName;
-    this.readOnly = ownerBean._ebean_getIntercept().isReadOnly();
+    this.readOnly = ownerBean != null && ownerBean._ebean_getIntercept().isReadOnly();
   }
 
   @Override
@@ -96,13 +95,6 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
     if (loader == null) {
       loader = (BeanCollectionLoader) Ebean.getServer(ebeanServerName);
     }
-    if (loader == null) {
-      String msg = "Lazy loading but LazyLoadEbeanServer is null?"
-        + " The LazyLoadEbeanServer needs to be set after deserialization"
-        + " to support lazy loading.";
-      throw new PersistenceException(msg);
-    }
-
     loader.loadMany(this, onlyIds);
     checkEmptyLazyLoad();
   }
@@ -215,7 +207,8 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
   /**
    * Return true if there are underlying additions or removals.
    */
-  boolean holdsModifications() {
+  @Override
+  public boolean holdsModifications() {
     return modifyHolder != null && modifyHolder.hasModifications();
   }
 

src/main/java/io/ebean/config/ServerConfig.java

@@ -488,6 +488,11 @@ public class ServerConfig {
    */
   private boolean defaultOrderById = false;
 
+  /**
+   * The mappingLocations for searching xml mapping.
+   */
+  private List<String> mappingLocations = new ArrayList<>();
+
   /**
    * Construct a Server Configuration for programmatically creating an EbeanServer.
    */
@@ -2780,10 +2785,8 @@ public class ServerConfig {
     dbOffline = p.getBoolean("dbOffline", dbOffline);
     serverCachePlugin = p.createInstance(ServerCachePlugin.class, "serverCachePlugin", serverCachePlugin);
 
-    if (packages != null) {
-      String packagesProp = p.get("search.packages", p.get("packages", null));
-      packages = getSearchJarsPackages(packagesProp);
-    }
+    String packagesProp = p.get("search.packages", p.get("packages", null));
+    packages = getSearchList(packagesProp, packages);
 
     collectQueryStatsByNode = p.getBoolean("collectQueryStatsByNode", collectQueryStatsByNode);
     collectQueryOrigins = p.getBoolean("collectQueryOrigins", collectQueryOrigins);
@@ -2862,10 +2865,13 @@ public class ServerConfig {
     tenantSchemaProvider = p.createInstance(TenantSchemaProvider.class, "tenant.schemaProvider", tenantSchemaProvider);
     tenantPartitionColumn = p.get("tenant.partitionColumn", tenantPartitionColumn);
     classes = getClasses(p);
+
+    String mappingsProp = p.get("mappingLocations", null);
+    mappingLocations = getSearchList(mappingsProp, mappingLocations);
   }
 
   private NamingConvention createNamingConvention(PropertiesWrapper properties, NamingConvention namingConvention) {
-    NamingConvention nc = properties.createInstance(NamingConvention.class, "namingconvention", null);
+    NamingConvention nc = properties.createInstance(NamingConvention.class, "namingConvention", null);
     return (nc != null) ? nc : namingConvention;
   }
 
@@ -2898,17 +2904,17 @@ public class ServerConfig {
     return classes;
   }
 
-  private List<String> getSearchJarsPackages(String searchPackages) {
+  private List<String> getSearchList(String searchNames, List<String> defaultValue) {
 
-    if (searchPackages != null) {
-      String[] entries = StringHelper.splitNames(searchPackages);
+    if (searchNames != null) {
+      String[] entries = StringHelper.splitNames(searchNames);
 
       List<String> hitList = new ArrayList<>(entries.length);
       Collections.addAll(hitList, entries);
 
       return hitList;
     } else {
-      return new ArrayList<>();
+      return defaultValue;
     }
   }
 
@@ -3076,6 +3082,33 @@ public class ServerConfig {
     return config;
   }
 
+  /**
+   * Add a mapping location to search for xml mapping via class path search.
+   */
+  public void addMappingLocation(String mappingLocation) {
+    if (mappingLocations == null) {
+      mappingLocations = new ArrayList<>();
+    }
+    mappingLocations.add(mappingLocation);
+  }
+
+  /**
+   * Return mapping locations to search for xml mapping via class path search.
+   */
+  public List<String> getMappingLocations() {
+    return mappingLocations;
+  }
+
+  /**
+   * Set mapping locations to search for xml mapping via class path search.
+   * <p>
+   * This is only used if classes have not been explicitly specified.
+   * </p>
+   */
+  public void setMappingLocations(List<String> mappingLocations) {
+    this.mappingLocations = mappingLocations;
+  }
+
   public enum UuidVersion {
     VERSION4,
     VERSION1,

src/main/java/io/ebean/config/UnderscoreNamingConvention.java

@@ -112,39 +112,7 @@ public class UnderscoreNamingConvention extends AbstractNamingConvention {
    * Convert and return the string to underscore from camel case.
    */
   protected String toUnderscoreFromCamel(String camelCase) {
-
-    int lastUpper = -1;
-    StringBuilder sb = new StringBuilder(camelCase.length() + 4);
-    for (int i = 0; i < camelCase.length(); i++) {
-      char c = camelCase.charAt(i);
-
-      if ('_' == c) {
-        // Underscores should just be passed through
-        sb.append(c);
-        lastUpper = i;
-      } else if (Character.isDigit(c)) {
-        if (i > lastUpper + 1 && !digitsCompressed) {
-          sb.append("_");
-        }
-        sb.append(c);
-        lastUpper = i;
-
-      } else if (Character.isUpperCase(c)) {
-        if (i > lastUpper + 1) {
-          sb.append("_");
-        }
-        sb.append(Character.toLowerCase(c));
-        lastUpper = i;
-
-      } else {
-        sb.append(c);
-      }
-    }
-    String ret = sb.toString();
-    if (forceUpperCase) {
-      ret = ret.toUpperCase();
-    }
-    return ret;
+    return CamelCaseHelper.toUnderscoreFromCamel(camelCase, digitsCompressed, forceUpperCase);
   }
 
   /**

src/main/java/io/ebean/util/CamelCaseHelper.java

@@ -2,6 +2,52 @@ package io.ebean.util;
 
 public class CamelCaseHelper {
 
+  /**
+   * To underscore from camel case using digits compressed true and force upper case false.
+   */
+  public static String toUnderscoreFromCamel(String camelCase) {
+    return toUnderscoreFromCamel(camelCase, true, false);
+  }
+
+  /**
+   * Convert and return the string to underscore from camel case.
+   */
+  public static String toUnderscoreFromCamel(String camelCase, boolean digitsCompressed, boolean forceUpperCase) {
+
+    int lastUpper = -1;
+    StringBuilder sb = new StringBuilder(camelCase.length() + 4);
+    for (int i = 0; i < camelCase.length(); i++) {
+      char c = camelCase.charAt(i);
+
+      if ('_' == c) {
+        // Underscores should just be passed through
+        sb.append(c);
+        lastUpper = i;
+      } else if (Character.isDigit(c)) {
+        if (i > lastUpper + 1 && !digitsCompressed) {
+          sb.append("_");
+        }
+        sb.append(c);
+        lastUpper = i;
+
+      } else if (Character.isUpperCase(c)) {
+        if (i > lastUpper + 1) {
+          sb.append("_");
+        }
+        sb.append(Character.toLowerCase(c));
+        lastUpper = i;
+
+      } else {
+        sb.append(c);
+      }
+    }
+    String ret = sb.toString();
+    if (forceUpperCase) {
+      ret = ret.toUpperCase();
+    }
+    return ret;
+  }
+
   /**
    * To camel from underscore.
    *

src/main/java/io/ebeaninternal/api/LoadManyRequest.java

@@ -1,6 +1,5 @@
 package io.ebeaninternal.api;
 
-import io.ebean.EbeanServer;
 import io.ebean.bean.BeanCollection;
 import io.ebean.bean.EntityBean;
 import io.ebean.util.StringHelper;
@@ -124,11 +123,11 @@ public class LoadManyRequest extends LoadRequest {
     return loadContext.getBeanProperty();
   }
 
-  public SpiQuery<?> createQuery(EbeanServer server, int batchSize) {
+  public SpiQuery<?> createQuery(SpiEbeanServer server, int batchSize) {
 
     BeanPropertyAssocMany<?> many = getMany();
 
-    SpiQuery<?> query = (SpiQuery<?>) server.createQuery(many.getTargetType());
+    SpiQuery<?> query = many.newQuery(server);
     String orderBy = many.getLazyFetchOrderBy();
     if (orderBy != null) {
       query.orderBy(orderBy);

src/main/java/io/ebeaninternal/api/SpiExpressionRequest.java

@@ -1,8 +1,8 @@
 package io.ebeaninternal.api;
 
-import io.ebeaninternal.server.core.DbExpressionHandler;
 import io.ebeaninternal.server.core.SpiOrmQueryRequest;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
+import io.ebeaninternal.server.expression.platform.DbExpressionHandler;
 
 import java.util.List;
 

src/main/java/io/ebeaninternal/api/SpiJsonContext.java

@@ -1,9 +1,11 @@
 package io.ebeaninternal.api;
 
 import com.fasterxml.jackson.core.JsonGenerator;
+import io.ebean.plugin.BeanType;
 import io.ebean.text.json.JsonContext;
 import io.ebean.text.json.JsonWriteOptions;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
 import java.io.Writer;
 
@@ -21,4 +23,10 @@ public interface SpiJsonContext extends JsonContext {
    * Create a Json Writer for writing beans as JSON supplying a writer.
    */
   SpiJsonWriter createJsonWriter(Writer writer);
+
+  /**
+   * Create a Json Reader for reading the JSON content.
+   */
+  SpiJsonReader createJsonRead(BeanType<?> beanType, String json);
+
 }

src/main/java/io/ebeaninternal/api/SpiSqlUpdate.java

@@ -23,4 +23,9 @@ public interface SpiSqlUpdate extends SqlUpdate {
    * Set the generated key value.
    */
   void setGeneratedKey(Object idValue);
+
+  /**
+   * Reset bind position to be ready for another bind execute.
+   */
+  void reset();
 }

src/main/java/io/ebeaninternal/api/SpiTransaction.java

@@ -319,4 +319,9 @@ public interface SpiTransaction extends Transaction {
    * Return the profile location for this transaction.
    */
   ProfileLocation getProfileLocation();
+
+  /**
+   * Return true when nested transactions should create Savepoints.
+   */
+  boolean isNestedUseSavepoint();
 }

src/main/java/io/ebeaninternal/api/SpiTransactionProxy.java

@@ -21,7 +21,7 @@ import java.sql.SQLException;
 /**
  * Proxy for an underlying SpiTransaction (most of the API).
  */
-abstract class SpiTransactionProxy implements SpiTransaction {
+public abstract class SpiTransactionProxy implements SpiTransaction {
 
   protected SpiTransaction transaction;
 
@@ -50,6 +50,16 @@ abstract class SpiTransactionProxy implements SpiTransaction {
     return transaction.isRollbackOnly();
   }
 
+  @Override
+  public void setNestedUseSavepoint() {
+    transaction.setNestedUseSavepoint();
+  }
+
+  @Override
+  public boolean isNestedUseSavepoint() {
+    return transaction.isNestedUseSavepoint();
+  }
+
   @Override
   public long profileOffset() {
     return transaction.profileOffset();

src/main/java/io/ebeaninternal/api/json/SpiJsonReader.java

@@ -0,0 +1,36 @@
+package io.ebeaninternal.api.json;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.ebean.bean.EntityBean;
+import io.ebean.bean.PersistenceContext;
+import io.ebeaninternal.server.deploy.BeanDescriptor;
+
+import java.io.IOException;
+import java.util.Map;
+
+public interface SpiJsonReader {
+
+  PersistenceContext getPersistenceContext();
+
+  SpiJsonReader forJson(JsonParser moreJson, boolean resetContext);
+
+  <T> void persistenceContextPut(Object beanId, T currentBean);
+
+  Object persistenceContextPutIfAbsent(Object id, EntityBean bean, BeanDescriptor<?> beanDesc);
+
+  ObjectMapper getObjectMapper();
+
+  JsonParser getParser();
+
+  JsonToken nextToken() throws IOException;
+
+  void pushPath(String path);
+
+  void popPath();
+
+  void beanVisitor(Object bean, Map<String, Object> unmappedProperties);
+
+  Object readValueUsingObjectMapper(Class<?> propertyType) throws IOException;
+}

src/main/java/io/ebeaninternal/api/json/SpiJsonWriter.java

@@ -1,9 +1,10 @@
-package io.ebeaninternal.server.text.json;
+package io.ebeaninternal.api.json;
 
 import io.ebean.bean.EntityBean;
 import io.ebean.text.json.JsonWriter;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
 
+import java.io.IOException;
 import java.util.Collection;
 
 /**
@@ -11,6 +12,11 @@ import java.util.Collection;
  */
 public interface SpiJsonWriter extends JsonWriter {
 
+  /**
+   * Flush the buffer.
+   */
+  void flush() throws IOException;
+
   /**
    * Return true if the value is a parent bean.
    */
@@ -60,7 +66,7 @@ public interface SpiJsonWriter extends JsonWriter {
    * Write value using underlying Jaskson object mapper if available.
    */
   void writeValueUsingObjectMapper(String name, Object value);
-  
+
   /**
    * Write the bean properties.
    */

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildContext.java

@@ -4,13 +4,18 @@ import io.ebean.config.DbConstraintNaming;
 import io.ebean.config.dbplatform.DbPlatformType;
 import io.ebean.config.dbplatform.DbPlatformTypeMapping;
 import io.ebeaninternal.dbmigration.model.MColumn;
+import io.ebeaninternal.dbmigration.model.MCompoundForeignKey;
 import io.ebeaninternal.dbmigration.model.MTable;
 import io.ebeaninternal.dbmigration.model.ModelContainer;
+import io.ebeaninternal.server.deploy.BeanDescriptor;
 import io.ebeaninternal.server.deploy.BeanProperty;
+import io.ebeaninternal.server.deploy.TableJoin;
+import io.ebeaninternal.server.deploy.TableJoinColumn;
 import io.ebeaninternal.server.type.ScalarType;
 
 import java.util.Collection;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * The context used during DDL generation.
@@ -187,4 +192,49 @@ public class ModelBuildContext {
     addTable(draftTable);
   }
 
+  /**
+   * Return a builder to add foreign keys.
+   */
+  public FkeyBuilder fkeyBuilder(MTable destTable) {
+    return new FkeyBuilder(this, destTable);
+  }
+
+  public static class FkeyBuilder {
+
+    private final AtomicInteger count = new AtomicInteger();
+
+    private final ModelBuildContext ctx;
+
+    private final MTable destTable;
+
+    private final String tableName;
+
+    FkeyBuilder(ModelBuildContext ctx, MTable destTable) {
+      this.ctx = ctx;
+      this.destTable = destTable;
+      this.tableName = destTable.getName();
+    }
+
+    /**
+     * Add a foreign key based on the table join.
+     */
+    public FkeyBuilder addForeignKey(BeanDescriptor<?> desc, TableJoin tableJoin, boolean direction) {
+
+      String baseTable = ctx.normaliseTable(desc.getBaseTable());
+      String fkName = ctx.foreignKeyConstraintName(tableName, baseTable, count.incrementAndGet());
+      String fkIndex = ctx.foreignKeyIndexName(tableName, baseTable, count.get());
+
+      MCompoundForeignKey foreignKey = new MCompoundForeignKey(fkName, desc.getBaseTable(), fkIndex);
+
+      for (TableJoinColumn column : tableJoin.columns()) {
+        String localCol = direction ? column.getForeignDbColumn() : column.getLocalDbColumn();
+        String refCol = !direction ? column.getForeignDbColumn() : column.getLocalDbColumn();
+        foreignKey.addColumnPair(localCol, refCol);
+      }
+
+      destTable.addForeignKey(foreignKey);
+      return this;
+    }
+
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildElementTable.java

@@ -0,0 +1,34 @@
+package io.ebeaninternal.dbmigration.model.build;
+
+import io.ebeaninternal.dbmigration.model.MTable;
+import io.ebeaninternal.dbmigration.model.visitor.VisitAllUsing;
+import io.ebeaninternal.server.deploy.BeanDescriptor;
+import io.ebeaninternal.server.deploy.BeanPropertyAssocMany;
+import io.ebeaninternal.server.deploy.BeanTable;
+
+/**
+ * Add the element collection table to the model.
+ */
+public class ModelBuildElementTable {
+
+  /**
+   * Build and add the MTable model for the ElementCollection property.
+   */
+  public static void build(ModelBuildContext ctx, BeanPropertyAssocMany<?> manyProp) {
+
+    BeanTable beanTable = manyProp.getBeanTable();
+
+    BeanDescriptor<?> targetDescriptor = manyProp.getTargetDescriptor();
+
+    MTable table = new MTable(beanTable.getBaseTable());
+
+    VisitAllUsing.visitOne(targetDescriptor, new ModelBuildPropertyVisitor(ctx, table, targetDescriptor));
+
+    ctx.fkeyBuilder(table)
+      .addForeignKey(manyProp.getBeanDescriptor(), manyProp.getTableJoin(), true);
+
+    ctx.addTable(table);
+  }
+
+
+}

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildIntersectionTable.java

@@ -1,7 +1,6 @@
 package io.ebeaninternal.dbmigration.model.build;
 
 import io.ebeaninternal.dbmigration.model.MColumn;
-import io.ebeaninternal.dbmigration.model.MCompoundForeignKey;
 import io.ebeaninternal.dbmigration.model.MTable;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
 import io.ebeaninternal.server.deploy.BeanProperty;
@@ -12,7 +11,7 @@ import io.ebeaninternal.server.deploy.TableJoinColumn;
 /**
  * Add the intersection table to the model.
  */
-public class ModelBuildIntersectionTable {
+class ModelBuildIntersectionTable {
 
   private final ModelBuildContext ctx;
 
@@ -22,9 +21,7 @@ public class ModelBuildIntersectionTable {
 
   private MTable intersectionTable;
 
-  private int countForeignKey;
-
-  public ModelBuildIntersectionTable(ModelBuildContext ctx, BeanPropertyAssocMany<?> manyProp) {
+  ModelBuildIntersectionTable(ModelBuildContext ctx, BeanPropertyAssocMany<?> manyProp) {
     this.ctx = ctx;
     this.manyProp = manyProp;
     this.intersectionTableJoin = manyProp.getIntersectionTableJoin();
@@ -51,33 +48,13 @@ public class ModelBuildIntersectionTable {
 
   private void buildFkConstraints() {
 
-    BeanDescriptor<?> localDesc = manyProp.getBeanDescriptor();
-    buildFkConstraints(localDesc, intersectionTableJoin.columns(), true);
-
-    BeanDescriptor<?> targetDesc = manyProp.getTargetDescriptor();
-    buildFkConstraints(targetDesc, tableJoin.columns(), false);
+    ctx.fkeyBuilder(intersectionTable)
+      .addForeignKey(manyProp.getBeanDescriptor(), intersectionTableJoin, true)
+      .addForeignKey(manyProp.getTargetDescriptor(), tableJoin, false);
 
     intersectionTable.checkDuplicateForeignKeys();
   }
 
-
-  private void buildFkConstraints(BeanDescriptor<?> desc, TableJoinColumn[] columns, boolean direction) {
-
-    String tableName = intersectionTableJoin.getTable();
-    String baseTable = ctx.normaliseTable(desc.getBaseTable());
-    String fkName = ctx.foreignKeyConstraintName(tableName, baseTable, ++countForeignKey);
-    String fkIndex = ctx.foreignKeyIndexName(tableName, baseTable, countForeignKey);
-
-    MCompoundForeignKey foreignKey = new MCompoundForeignKey(fkName, desc.getBaseTable(), fkIndex);
-    intersectionTable.addForeignKey(foreignKey);
-
-    for (TableJoinColumn column : columns) {
-      String localCol = direction ? column.getForeignDbColumn() : column.getLocalDbColumn();
-      String refCol = !direction ? column.getForeignDbColumn() : column.getLocalDbColumn();
-      foreignKey.addColumnPair(localCol, refCol);
-    }
-  }
-
   private MTable createTable() {
 
     BeanDescriptor<?> localDesc = manyProp.getBeanDescriptor();

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildPropertyVisitor.java

@@ -123,27 +123,24 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
 
   @Override
   public void visitMany(BeanPropertyAssocMany<?> p) {
-    if (p.hasJoinTable()) {
-      if (p.getMappedBy() == null) {
-        // only create on other 'owning' side
+    if (p.hasJoinTable() && p.getMappedBy() == null) {
+      // only create on other 'owning' side
 
-        //TableJoin intersectionTableJoin = p.getIntersectionTableJoin();
-        // check if the intersection table has already been created
-
-        // build the create table and fkey constraints
-        // putting the DDL into ctx for later output as we are
-        // in the middle of rendering the create table DDL
-        MTable intersectionTable = new ModelBuildIntersectionTable(ctx, p).build();
-        if (p.isO2mJoinTable()) {
-          intersectionTable.clearForeignKeyIndexes();
-          Collection<MColumn> cols = intersectionTable.allColumns();
-          if (cols.size() == 2) {
-            // always the second column that we put the unique constraint on
-            MColumn col = new ArrayList<>(cols).get(1);
-            col.setUnique(determineUniqueConstraintName(col.getName()));
-          }
+      // build the create table and fkey constraints
+      // putting the DDL into ctx for later output as we are
+      // in the middle of rendering the create table DDL
+      MTable intersectionTable = new ModelBuildIntersectionTable(ctx, p).build();
+      if (p.isO2mJoinTable()) {
+        intersectionTable.clearForeignKeyIndexes();
+        Collection<MColumn> cols = intersectionTable.allColumns();
+        if (cols.size() == 2) {
+          // always the second column that we put the unique constraint on
+          MColumn col = new ArrayList<>(cols).get(1);
+          col.setUnique(determineUniqueConstraintName(col.getName()));
         }
       }
+    } else if (p.isElementCollection()) {
+      ModelBuildElementTable.build(ctx, p);
     }
   }
 

src/main/java/io/ebeaninternal/dbmigration/model/visitor/VisitAllUsing.java

@@ -16,6 +16,14 @@ import java.util.List;
  */
 public class VisitAllUsing {
 
+  /**
+   * Visit a single Descriptor using the given visitor.
+   */
+  public static void visitOne(BeanDescriptor<?> descriptor, BeanPropertyVisitor visitor) {
+
+    new VisitAllUsing().visitProperties(descriptor, visitor);
+  }
+
   protected final BeanVisitor visitor;
 
   protected final List<BeanDescriptor<?>> descriptors;
@@ -36,6 +44,11 @@ public class VisitAllUsing {
     this.descriptors = descriptors;
   }
 
+  private VisitAllUsing() {
+    this.visitor = null;
+    this.descriptors = null;
+  }
+
   public void visitAllBeans() {
     for (BeanDescriptor<?> desc : descriptors) {
       if (desc.isBaseTable()) {
@@ -51,29 +64,32 @@ public class VisitAllUsing {
 
     BeanPropertyVisitor propertyVisitor = visitor.visitBean(desc);
     if (propertyVisitor != null) {
-
-      BeanProperty idProp = desc.getIdProperty();
-      if (idProp != null) {
-        visit(propertyVisitor, idProp);
-      }
-
-      BeanPropertyAssocOne<?> unidirectional = desc.getUnidirectional();
-      if (unidirectional != null) {
-        visit(propertyVisitor, unidirectional);
-      }
-
-      BeanProperty[] propertiesNonTransient = desc.propertiesNonTransient();
-      for (BeanProperty p : propertiesNonTransient) {
-        if (p.isDDLColumn()) {
-          visit(propertyVisitor, p);
-        }
-      }
-
-      visitInheritanceProperties(desc, propertyVisitor);
-      propertyVisitor.visitEnd();
+      visitProperties(desc, propertyVisitor);
     }
   }
 
+  private void visitProperties(BeanDescriptor<?> desc, BeanPropertyVisitor propertyVisitor) {
+    BeanProperty idProp = desc.getIdProperty();
+    if (idProp != null) {
+      visit(propertyVisitor, idProp);
+    }
+
+    BeanPropertyAssocOne<?> unidirectional = desc.getUnidirectional();
+    if (unidirectional != null) {
+      visit(propertyVisitor, unidirectional);
+    }
+
+    BeanProperty[] propertiesNonTransient = desc.propertiesNonTransient();
+    for (BeanProperty p : propertiesNonTransient) {
+      if (p.isDDLColumn()) {
+        visit(propertyVisitor, p);
+      }
+    }
+
+    visitInheritanceProperties(desc, propertyVisitor);
+    propertyVisitor.visitEnd();
+  }
+
   /**
    * Visit the property.
    */

src/main/java/io/ebeaninternal/server/autotune/service/ProfileOriginNodeUsage.java

@@ -2,11 +2,11 @@ package io.ebeaninternal.server.autotune.service;
 
 import io.ebean.bean.NodeUsageCollector;
 import io.ebean.text.PathProperties;
+import io.ebean.util.SplitName;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
 import io.ebeaninternal.server.deploy.BeanProperty;
 import io.ebeaninternal.server.deploy.BeanPropertyAssoc;
 import io.ebeaninternal.server.el.ElPropertyValue;
-import io.ebean.util.SplitName;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -56,7 +56,7 @@ public class ProfileOriginNodeUsage {
       }
 
       for (String propName : aggregateUsed) {
-        BeanProperty beanProp = desc.getBeanPropertyFromPath(propName);
+        BeanProperty beanProp = desc.findPropertyFromPath(propName);
         if (beanProp == null) {
           logger.warn("AutoTune: Can't find property[" + propName + "] for " + desc.getName());
 

src/main/java/io/ebeaninternal/server/cache/CachedBeanDataFromBean.java

@@ -4,6 +4,7 @@ import io.ebean.bean.EntityBean;
 import io.ebean.bean.EntityBeanIntercept;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
 import io.ebeaninternal.server.deploy.BeanProperty;
+import io.ebeaninternal.server.deploy.BeanPropertyAssocMany;
 
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -33,6 +34,12 @@ public class CachedBeanDataFromBean {
       }
     }
 
+    for (BeanPropertyAssocMany<?> prop : desc.propertiesMany()) {
+      if (prop.isElementCollection()) {
+        data.put(prop.getName(), prop.getCacheDataValue(bean));
+      }
+    }
+
     long version = desc.getVersion(bean);
     EntityBean sharableBean = createSharableBean(desc, bean, ebi);
     return new CachedBeanData(sharableBean, desc.getDiscValue(), data, version);

src/main/java/io/ebeaninternal/server/cache/CachedBeanDataToBean.java

@@ -15,20 +15,26 @@ public class CachedBeanDataToBean {
     EntityBeanIntercept ebi = bean._ebean_getIntercept();
 
     BeanProperty idProperty = desc.getIdProperty();
+    if (desc.getInheritInfo() != null) {
+        desc = desc.getInheritInfo().readType(bean.getClass()).desc();
+    }
+
     if (idProperty != null) {
       // load the id property
       loadProperty(bean, cacheBeanData, ebi, idProperty, context);
     }
 
     // load the non-many properties
-    BeanProperty[] props = desc.propertiesNonMany();
-    for (BeanProperty prop : props) {
+    for (BeanProperty prop : desc.propertiesNonMany()) {
       loadProperty(bean, cacheBeanData, ebi, prop, context);
     }
 
-    BeanPropertyAssocMany<?>[] many = desc.propertiesMany();
-    for (BeanPropertyAssocMany<?> aMany : many) {
-      aMany.createReferenceIfNull(bean);
+    for (BeanPropertyAssocMany<?> prop : desc.propertiesMany()) {
+      if (prop.isElementCollection()) {
+        loadProperty(bean, cacheBeanData, ebi, prop, context);
+      } else {
+        prop.createReferenceIfNull(bean);
+      }
     }
 
     ebi.setLoadedLazy();

src/main/java/io/ebeaninternal/server/core/BaseDbExpression.java

@@ -1,19 +0,0 @@
-package io.ebeaninternal.server.core;
-
-/**
- * Not supported JSON or ARRAY expression handler.
- */
-abstract class BaseDbExpression implements DbExpressionHandler {
-
-  private final String concatOperator;
-
-  BaseDbExpression(String concatOperator) {
-    this.concatOperator = concatOperator;
-  }
-
-  @Override
-  public String getConcatOperator() {
-    return concatOperator;
-  }
-
-}

src/main/java/io/ebeaninternal/server/core/DefaultServer.java

@@ -802,7 +802,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
    */
   @Override
   public void commitTransaction() {
-    transactionManager.scope().commit();
+    currentTransaction().commit();
   }
 
   /**
@@ -810,7 +810,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
    */
   @Override
   public void rollbackTransaction() {
-    transactionManager.scope().rollback();
+    currentTransaction().rollback();
   }
 
   /**
@@ -843,7 +843,10 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
    */
   @Override
   public void endTransaction() {
-    transactionManager.scope().end();
+    Transaction transaction = transactionManager.getInScope();
+    if (transaction != null) {
+      transaction.end();
+    }
   }
 
   /**
@@ -966,7 +969,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
   }
 
   @Override
-  public <T> Query<T> createQuery(Class<T> beanType, String eql) {
+  public <T> DefaultOrmQuery<T> createQuery(Class<T> beanType, String eql) {
     DefaultOrmQuery<T> query = createQuery(beanType);
     EqlParser.parse(eql, query);
     return query;
@@ -999,6 +1002,16 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
     return new DefaultDtoQuery<>(this, descriptor, sql.trim());
   }
 
+  @Override
+  public <T> DtoQuery<T> createNamedDtoQuery(Class<T> dtoType, String namedQuery) {
+    DtoBeanDescriptor<T> descriptor = dtoBeanManager.getDescriptor(dtoType);
+    String sql = descriptor.getNamedRawSql(namedQuery);
+    if (sql == null) {
+      throw new PersistenceException("No named query called " + namedQuery + " for bean:" + dtoType.getName());
+    }
+    return new DefaultDtoQuery<>(this, descriptor, sql);
+  }
+
   @Override
   public <T> DtoQuery<T> findDto(Class<T> dtoType, SpiQuery<?> ormQuery) {
 

src/main/java/io/ebeaninternal/server/core/DefaultSqlUpdate.java

@@ -97,6 +97,11 @@ public final class DefaultSqlUpdate implements Serializable, SpiSqlUpdate {
     this(null, sql, new BindParams());
   }
 
+  @Override
+  public void reset() {
+    addPos = 0;
+  }
+
   @Override
   public Object executeGetKey() {
     execute();
@@ -182,8 +187,9 @@ public final class DefaultSqlUpdate implements Serializable, SpiSqlUpdate {
     return this;
   }
 
-  public void addParameter(Object value) {
+  public SqlUpdate setNextParameter(Object value) {
     setParameter(++addPos, value);
+    return this;
   }
 
   @Override

src/main/java/io/ebeaninternal/server/core/InternalConfigXmlRead.java

@@ -0,0 +1,108 @@
+package io.ebeaninternal.server.core;
+
+import io.ebean.config.ServerConfig;
+import io.ebeaninternal.server.dto.DtoNamedQueries;
+import io.ebeaninternal.xmlmapping.XmlMappingReader;
+import io.ebeaninternal.xmlmapping.model.XmDto;
+import io.ebeaninternal.xmlmapping.model.XmEbean;
+import io.ebeaninternal.xmlmapping.model.XmRawSql;
+import org.avaje.classpath.scanner.ClassPathScanner;
+import org.avaje.classpath.scanner.Resource;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Reads the Xml deployment information.
+ */
+class InternalConfigXmlRead {
+
+  private static final Logger log = LoggerFactory.getLogger(InternalConfigXmlRead.class);
+
+  private final ServerConfig serverConfig;
+
+  private final ClassLoader classLoader;
+
+  private final Map<Class<?>, DtoNamedQueries> dtoNamedQueries = new HashMap<>();
+
+  private List<XmEbean> xmlEbeanList;
+
+  InternalConfigXmlRead(ServerConfig serverConfig) {
+    this.serverConfig = serverConfig;
+    this.classLoader = serverConfig.getClassLoadConfig().getClassLoader();
+
+    init();
+  }
+
+  private void init() {
+    this.xmlEbeanList = XmlMappingReader.readByResourceName(classLoader, "ebean.xml");
+    xmlEbeanList.addAll(XmlMappingReader.readByResourceList(xmlMappingResources()));
+  }
+
+  private List<Resource> xmlMappingResources() {
+    List<ClassPathScanner> scanners = ClassPathScanners.find(serverConfig);
+    List<String> mappingLocations = serverConfig.getMappingLocations();
+    List<Resource> resourceList = new ArrayList<>();
+
+    long st = System.currentTimeMillis();
+    if (mappingLocations != null && !mappingLocations.isEmpty()) {
+      for (ClassPathScanner finder : scanners) {
+        for (String mappingLocation : mappingLocations) {
+          resourceList.addAll(finder.scanForResources(mappingLocation, resourceName -> resourceName.endsWith(".xml")));
+        }
+      }
+    }
+
+    long searchTime = System.currentTimeMillis() - st;
+    log.debug("Classpath search mappings[{}] searchTime[{}]", resourceList.size(), searchTime);
+    return resourceList;
+  }
+
+  /**
+   * Return the XML deployment information for entity beans.
+   */
+  List<XmEbean> xmlDeployment() {
+    return xmlEbeanList;
+  }
+
+  /**
+   * Return the named queries for Dto beans.
+   */
+  Map<Class<?>, DtoNamedQueries> readDtoMapping() {
+    for (XmEbean mapping : xmlEbeanList) {
+      List<XmDto> dtoList = mapping.getDto();
+      for (XmDto dto : dtoList) {
+        readDtoMapping(dto);
+      }
+    }
+
+    return dtoNamedQueries;
+  }
+
+  private void readDtoMapping(XmDto dto) {
+
+    String dtoClassName = dto.getClazz();
+    Class<?> dtoClass;
+    try {
+      dtoClass = Class.forName(dtoClassName, false, classLoader);
+    } catch (Exception e) {
+      log.error("Could not load dto bean class " + dtoClassName + " for ebean xml entry");
+      return;
+    }
+
+    DtoNamedQueries namedQueries = dtoNamedQueries.computeIfAbsent(dtoClass, aClass -> new DtoNamedQueries());
+
+    for (XmRawSql sql : dto.getRawSql()) {
+      namedQueries.addRawSql(sql.getName(), sql.getQuery().getValue());
+    }
+
+    if (!dto.getNamedQuery().isEmpty()) {
+      log.error("Only raw-sql named queries supported for DTO beans - bean:" + dtoClass);
+    }
+  }
+
+}

src/main/java/io/ebeaninternal/server/core/InternalConfiguration.java

@@ -42,6 +42,8 @@ import io.ebeaninternal.server.deploy.parse.DeployInherit;
 import io.ebeaninternal.server.deploy.parse.DeployUtil;
 import io.ebeaninternal.server.dto.DtoBeanManager;
 import io.ebeaninternal.server.expression.DefaultExpressionFactory;
+import io.ebeaninternal.server.expression.platform.DbExpressionHandler;
+import io.ebeaninternal.server.expression.platform.DbExpressionHandlerFactory;
 import io.ebeaninternal.server.persist.Binder;
 import io.ebeaninternal.server.persist.DefaultPersister;
 import io.ebeaninternal.server.persist.platform.MultiValueBind;
@@ -153,10 +155,12 @@ public class InternalConfiguration {
 
     this.deployCreateProperties = new DeployCreateProperties(typeManager);
     this.deployUtil = new DeployUtil(typeManager, serverConfig);
-    this.dtoBeanManager = new DtoBeanManager(typeManager);
 
+    InternalConfigXmlRead xmlRead = new InternalConfigXmlRead(serverConfig);
+
+    this.dtoBeanManager = new DtoBeanManager(typeManager, xmlRead.readDtoMapping());
     this.beanDescriptorManager = new BeanDescriptorManager(this);
-    Map<String, String> asOfTableMapping = beanDescriptorManager.deploy();
+    Map<String, String> asOfTableMapping = beanDescriptorManager.deploy(xmlRead.xmlDeployment());
     Map<String, String> draftTableMap = beanDescriptorManager.getDraftTableMap();
     beanDescriptorManager.scheduleBackgroundTrim();
 
@@ -267,18 +271,7 @@ public class InternalConfiguration {
    * Return the JSON expression handler for the given database platform.
    */
   private DbExpressionHandler getDbExpressionHandler(DatabasePlatform databasePlatform) {
-    Platform platform = databasePlatform.getPlatform();
-    String concatOperator = databasePlatform.getConcatOperator();
-    switch (platform) {
-      case POSTGRES:
-        return new PostgresDbExpression(concatOperator);
-      case ORACLE:
-        return new OracleDbExpression(concatOperator);
-      case SQLSERVER:
-        return new SqlServerDbExpression(concatOperator);
-      default:
-        return new BasicDbExpression(concatOperator);
-    }
+    return DbExpressionHandlerFactory.from(databasePlatform);
   }
 
   private MultiValueBind createMultiValueBind(Platform platform) {

src/main/java/io/ebeaninternal/server/core/OrmQueryRequest.java

@@ -79,6 +79,8 @@ public final class OrmQueryRequest<T> extends BeanRequest implements SpiOrmQuery
 
   private List<T> cacheBeans;
 
+  private BeanPropertyAssocMany<?> manyProperty;
+
   /**
    * Create the InternalQueryRequest.
    */
@@ -496,11 +498,18 @@ public final class OrmQueryRequest<T> extends BeanRequest implements SpiOrmQuery
   }
 
   /**
-   * Return the many property that is fetched in the query or null if there is
-   * not one.
+   * Determine and return the ToMany property that is included in the query.
+   */
+  public BeanPropertyAssocMany<?> determineMany() {
+    manyProperty = beanDescriptor.getManyProperty(query);
+    return manyProperty;
+  }
+
+  /**
+   * Return the many property that is fetched in the query or null if there is not one.
    */
   public BeanPropertyAssocMany<?> getManyProperty() {
-    return beanDescriptor.getManyProperty(query);
+    return manyProperty;
   }
 
   /**

src/main/java/io/ebeaninternal/server/core/PersistRequestBean.java

@@ -35,6 +35,7 @@ import javax.persistence.PersistenceException;
 import java.io.IOException;
 import java.sql.Statement;
 import java.util.ArrayList;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -107,6 +108,11 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
    */
   private boolean updatedManysOnly;
 
+  /**
+   * Element collection change as part of bean cache.
+   */
+  private Map<String, Object> collectionChanges;
+
   /**
    * Many properties that were cascade saved (and hence might need caches updated later).
    */
@@ -154,6 +160,11 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
    */
   private boolean getterCallback;
 
+  /**
+   * postUpdate notifications. Used to combine bean and element update updates into single postUpdate event.
+   */
+  private int pendingPostUpdateNotify;
+
   public PersistRequestBean(SpiEbeanServer server, T bean, Object parentBean, BeanManager<T> mgr, SpiTransaction t,
                             PersistExecute persistExecute, PersistRequest.Type type, int flags) {
 
@@ -337,11 +348,16 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
 
   @Override
   public void preGetterTrigger(int propertyIndex) {
-    if (propertyIndex < 0 || beanDescriptor.isGeneratedProperty(propertyIndex)) {
+    if (flushBatchOnGetter(propertyIndex)) {
       transaction.flushBatch();
     }
   }
 
+  private boolean flushBatchOnGetter(int propertyIndex) {
+    // propertyIndex of -1 the Id property, no flush for get Id on UPDATE
+    return propertyIndex == -1 ? type == Type.INSERT : beanDescriptor.isGeneratedProperty(propertyIndex);
+  }
+
   public void setSkipBatchForTopLevel() {
     skipBatchForTopLevel = true;
   }
@@ -858,6 +874,16 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
     }
   }
 
+  private void postUpdateNotify() {
+    if (pendingPostUpdateNotify > 0) {
+      // invoke the delayed postUpdate notification (combined with element collection update)
+      controller.postUpdate(this);
+    } else {
+      // batched update with no element collection, send postUpdate notification once it executes
+      pendingPostUpdateNotify = -1;
+    }
+  }
+
   /**
    * Aggressive L1 and L2 cache cleanup for deletes.
    */
@@ -905,13 +931,42 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
     }
   }
 
+  /**
+   * Ensure the preUpdate event fires (for case where only element collection has changed).
+   */
+  public void preElementCollectionUpdate() {
+    if (controller != null && !dirty) {
+      // fire preUpdate notification when only element collection updated
+      controller.preUpdate(this);
+    }
+  }
+
+  /**
+   * Combine with the beans postUpdate event notification.
+   */
+  public boolean postElementCollectionUpdate() {
+    if (controller != null) {
+      pendingPostUpdateNotify += 2;
+    }
+    if (!dirty) {
+      setNotifyCache();
+    }
+    return notifyCache;
+  }
+
   private void controllerPost() {
     switch (type) {
       case INSERT:
         controller.postInsert(this);
         break;
       case UPDATE:
-        controller.postUpdate(this);
+        if (pendingPostUpdateNotify == -1) {
+          // notify now - batched bean update with no element collection
+          controller.postUpdate(this);
+        } else {
+          // delay notify to combine with element collection update
+          pendingPostUpdateNotify++;
+        }
         break;
       case SOFT_DELETE:
         controller.postSoftDelete(this);
@@ -1031,13 +1086,7 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
       setNotifyCache();
       addEvent();
     }
-  }
-
-  /**
-   * Return true if only many properties where updated.
-   */
-  public boolean isUpdatedManysOnly() {
-    return updatedManysOnly;
+    postUpdateNotify();
   }
 
   /**
@@ -1265,4 +1314,50 @@ public final class PersistRequestBean<T> extends PersistRequest implements BeanP
   public boolean isInsertedParent() {
     return Flags.isInsert(flags);
   }
+
+  /**
+   * Add an element collection change to L2 bean cache update.
+   */
+  public void addCollectionChange(String name, Object value) {
+    if (collectionChanges == null) {
+      collectionChanges = new LinkedHashMap<>();
+    }
+    collectionChanges.put(name, value);
+  }
+
+  /**
+   * Build the bean update for the L2 cache.
+   */
+  public void addBeanUpdate(CacheChangeSet changeSet) {
+
+    if (!updatedManysOnly || collectionChanges != null) {
+
+      boolean updateNaturalKey = false;
+
+      Map<String, Object> changes = new LinkedHashMap<>();
+      EntityBean bean = getEntityBean();
+      boolean[] dirtyProperties = getDirtyProperties();
+      if (dirtyProperties != null) {
+        for (int i = 0; i < dirtyProperties.length; i++) {
+          if (dirtyProperties[i]) {
+            BeanProperty property = beanDescriptor.propertyByIndex(i);
+            if (property.isCacheDataInclude()) {
+              Object val = property.getCacheDataValue(bean);
+              changes.put(property.getName(), val);
+              if (property.isNaturalKey()) {
+                updateNaturalKey = true;
+                changeSet.addNaturalKeyPut(beanDescriptor, idValue, val);
+              }
+            }
+          }
+        }
+      }
+      if (collectionChanges != null) {
+        // add element collection update
+        changes.putAll(collectionChanges);
+      }
+
+      changeSet.addBeanUpdate(beanDescriptor, idValue, changes, updateNaturalKey, getVersion());
+    }
+  }
 }

src/main/java/io/ebeaninternal/server/core/PersistRequestUpdateSql.java

@@ -30,12 +30,13 @@ public final class PersistRequestUpdateSql extends PersistRequest {
   /**
    * Create.
    */
-  public PersistRequestUpdateSql(SpiEbeanServer server, SqlUpdate updateSql,
+  public PersistRequestUpdateSql(SpiEbeanServer server, SqlUpdate sqlUpdate,
                                  SpiTransaction t, PersistExecute persistExecute) {
 
-    super(server, t, persistExecute, updateSql.getLabel());
+    super(server, t, persistExecute, sqlUpdate.getLabel());
     this.type = Type.UPDATESQL;
-    this.updateSql = (SpiSqlUpdate) updateSql;
+    this.updateSql = (SpiSqlUpdate) sqlUpdate;
+    updateSql.reset();
   }
 
   @Override

src/main/java/io/ebeaninternal/server/core/ServletContextListener.java

@@ -1,32 +0,0 @@
-package io.ebeaninternal.server.core;
-
-import io.ebeaninternal.server.lib.ShutdownManager;
-
-import javax.servlet.ServletContextEvent;
-
-/**
- * Listens for webserver server starting and stopping events.
- * <p>
- * Register this listener in the web.xml configuration file. This will listen
- * for startup and shutdown events.
- * </p>
- */
-public class ServletContextListener implements javax.servlet.ServletContextListener {
-
-  /**
-   * The servlet container is stopping.
-   */
-  @Override
-  public void contextDestroyed(ServletContextEvent event) {
-    ShutdownManager.shutdown();
-  }
-
-  /**
-   * Do nothing on startup.
-   */
-  @Override
-  public void contextInitialized(ServletContextEvent event) {
-
-  }
-
-}

src/main/java/io/ebeaninternal/server/deploy/BaseCollectionHelp.java

@@ -1,11 +1,47 @@
 package io.ebeaninternal.server.deploy;
 
 import io.ebean.bean.BeanCollection;
+import io.ebean.bean.BeanCollectionLoader;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
+import java.io.IOException;
 import java.util.Collection;
 
 abstract class BaseCollectionHelp<T> implements BeanCollectionHelp<T> {
 
+  final BeanPropertyAssocMany<T> many;
+  final BeanDescriptor<T> targetDescriptor;
+  final String propertyName;
+
+  BeanCollectionLoader loader;
+
+  BaseCollectionHelp(BeanPropertyAssocMany<T> many) {
+    this.many = many;
+    this.targetDescriptor = many.getTargetDescriptor();
+    this.propertyName = many.getName();
+  }
+
+   BaseCollectionHelp() {
+    this.many = null;
+    this.targetDescriptor = null;
+    this.propertyName = null;
+  }
+
+  @Override
+  public void setLoader(BeanCollectionLoader loader) {
+    this.loader = loader;
+  }
+
+  @Override
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    if (withCheck) {
+      collection.internalAddWithCheck(bean);
+    } else {
+      collection.internalAdd(bean);
+    }
+  }
+
   @Override
   public Collection underlying(Object value) {
     if (value instanceof BeanCollection) {
@@ -14,4 +50,18 @@ abstract class BaseCollectionHelp<T> implements BeanCollectionHelp<T> {
       return (Collection)value;
     }
   }
+
+  void jsonWriteCollection(SpiJsonWriter ctx, String name, Collection<?> list) throws IOException {
+    if (!list.isEmpty() || ctx.isIncludeEmpty()) {
+      ctx.beginAssocMany(name);
+      for (Object bean : list) {
+        jsonWriteElement(ctx, bean);
+      }
+      ctx.endAssocMany();
+    }
+  }
+
+  void jsonWriteElement(SpiJsonWriter ctx, Object bean) throws IOException {
+    targetDescriptor.jsonWrite(ctx, (EntityBean) bean);
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/BeanChangeJson.java

@@ -2,7 +2,7 @@ package io.ebeaninternal.server.deploy;
 
 import io.ebean.PersistenceIOException;
 import io.ebean.bean.BeanDiffVisitor;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 import io.ebeaninternal.server.util.ArrayStack;
 
 import java.io.IOException;
@@ -82,10 +82,10 @@ class BeanChangeJson implements BeanDiffVisitor {
   void flush() {
     try {
       newJson.writeEndObject();
-      newJson.gen().flush();
+      newJson.flush();
       if (oldJson != null) {
         oldJson.writeEndObject();
-        oldJson.gen().flush();
+        oldJson.flush();
       }
     } catch (IOException e) {
       throw new PersistenceIOException(e);

src/main/java/io/ebeaninternal/server/deploy/BeanCollectionHelp.java

@@ -7,7 +7,8 @@ import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollectionAdd;
 import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+import io.ebeaninternal.server.query.CQueryCollectionAdd;
 
 import java.io.IOException;
 import java.util.Collection;
@@ -15,7 +16,7 @@ import java.util.Collection;
 /**
  * Helper functions for performing tasks on Lists Sets or Maps.
  */
-public interface BeanCollectionHelp<T> {
+public interface BeanCollectionHelp<T> extends CQueryCollectionAdd<T> {
 
   /**
    * Set the EbeanServer that owns the configuration.

src/main/java/io/ebeaninternal/server/deploy/BeanCollectionHelpFactory.java

@@ -18,16 +18,17 @@ public class BeanCollectionHelpFactory {
   /**
    * Create the helper based on the many property.
    */
-  public static <T> BeanCollectionHelp<T> create(BeanPropertyAssocMany<T> manyProperty) {
+  public static <T> BeanCollectionHelp<T> create(BeanPropertyAssocMany<T> many) {
 
-    ManyType manyType = manyProperty.getManyType();
+    boolean elementCollection = many.isElementCollection();
+    ManyType manyType = many.getManyType();
     switch (manyType) {
       case LIST:
-        return new BeanListHelp<>(manyProperty);
+        return elementCollection ? new BeanListHelpElement<>(many) : new BeanListHelp<>(many);
       case SET:
-        return new BeanSetHelp<>(manyProperty);
+        return elementCollection ? new BeanSetHelpElement<>(many) : new BeanSetHelp<>(many);
       case MAP:
-        return new BeanMapHelp<>(manyProperty);
+        return elementCollection ? new BeanMapHelpElement<>(many) :new BeanMapHelp<>(many);
       default:
         throw new RuntimeException("Invalid type " + manyType);
     }
@@ -35,9 +36,7 @@ public class BeanCollectionHelpFactory {
   }
 
   @SuppressWarnings("unchecked")
-  public static <T> BeanCollectionHelp<T> create(OrmQueryRequest<T> request) {
-
-    SpiQuery.Type manyType = request.getQuery().getType();
+  public static <T> BeanCollectionHelp<T> create(SpiQuery.Type manyType, OrmQueryRequest<T> request) {
 
     if (manyType == SpiQuery.Type.LIST) {
       return LIST_HELP;

src/main/java/io/ebeaninternal/server/deploy/BeanCollectionUtil.java

@@ -11,6 +11,16 @@ import java.util.Map;
  */
 public class BeanCollectionUtil {
 
+  /**
+   * Return true if this is a bean collection and not considered dirty.
+   */
+  public static boolean isModified(Object collection) {
+    if ((collection instanceof BeanCollection<?>)) {
+      return ((BeanCollection<?>) collection).holdsModifications();
+    }
+    return true;
+  }
+
   /**
    * Return the details of the collection or map taking care to avoid
    * unnecessary fetching of the data.

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptor.java

@@ -41,6 +41,8 @@ import io.ebeaninternal.api.SpiEbeanServer;
 import io.ebeaninternal.api.SpiQuery;
 import io.ebeaninternal.api.SpiUpdatePlan;
 import io.ebeaninternal.api.TransactionEventTable.TableIUD;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 import io.ebeaninternal.server.cache.CacheChangeSet;
 import io.ebeaninternal.server.cache.CachedBeanData;
 import io.ebeaninternal.server.cache.CachedManyIds;
@@ -62,11 +64,16 @@ import io.ebeaninternal.server.el.ElPropertyDeploy;
 import io.ebeaninternal.server.el.ElPropertyValue;
 import io.ebeaninternal.server.persist.DmlUtil;
 import io.ebeaninternal.server.query.CQueryPlan;
-import io.ebeaninternal.server.query.SqlTreeProperty;
+import io.ebeaninternal.server.query.ExtraJoin;
+import io.ebeaninternal.server.query.STreeProperty;
+import io.ebeaninternal.server.query.STreePropertyAssoc;
+import io.ebeaninternal.server.query.STreePropertyAssocMany;
+import io.ebeaninternal.server.query.STreePropertyAssocOne;
+import io.ebeaninternal.server.query.STreeType;
+import io.ebeaninternal.server.query.SqlBeanLoad;
+import io.ebeaninternal.server.querydefn.DefaultOrmQuery;
 import io.ebeaninternal.server.querydefn.OrmQueryDetail;
 import io.ebeaninternal.server.rawsql.SpiRawSql;
-import io.ebeaninternal.server.text.json.ReadJson;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
 import io.ebeaninternal.server.type.DataBind;
 import io.ebeaninternal.server.type.ScalarType;
 import io.ebeaninternal.util.SortByClause;
@@ -100,7 +107,7 @@ import java.util.concurrent.ConcurrentHashMap;
 /**
  * Describes Beans including their deployment information.
  */
-public class BeanDescriptor<T> implements BeanType<T> {
+public class BeanDescriptor<T> implements BeanType<T>, STreeType {
 
   private static final Logger logger = LoggerFactory.getLogger(BeanDescriptor.class);
 
@@ -114,7 +121,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
 
   private final ConcurrentHashMap<String, ElComparator<T>> comparatorCache = new ConcurrentHashMap<>();
 
-  private final ConcurrentHashMap<String, SqlTreeProperty> dynamicProperty = new ConcurrentHashMap<>();
+  private final ConcurrentHashMap<String, STreeProperty> dynamicProperty = new ConcurrentHashMap<>();
 
   private final Map<String, SpiRawSql> namedRawSql;
 
@@ -229,7 +236,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
   /**
    * The type of bean this describes.
    */
-  private final Class<T> beanType;
+  final Class<T> beanType;
 
   protected final Class<?> rootBeanType;
 
@@ -239,7 +246,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
   private final BeanDescriptorMap owner;
 
 
-  private final String[] properties;
+  final String[] properties;
 
   /**
    * Intercept pre post on insert,update, and delete .
@@ -400,7 +407,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
 
   private final BeanDescriptorDraftHelp<T> draftHelp;
   private final BeanDescriptorCacheHelp<T> cacheHelp;
-  private final BeanDescriptorJsonHelp<T> jsonHelp;
+  final BeanDescriptorJsonHelp<T> jsonHelp;
   private DocStoreBeanAdapter<T> docStoreAdapter;
   private DocumentMapping docMapping;
   private boolean docStoreEmbeddedInvalidation;
@@ -422,8 +429,8 @@ public class BeanDescriptor<T> implements BeanType<T> {
     this.name = InternString.intern(deploy.getName());
     this.baseTableAlias = "t0";
     this.fullName = InternString.intern(deploy.getFullName());
-    this.locationById = ProfileLocation.createAt(fullName+".byId");
-    this.locationAll = ProfileLocation.createAt(fullName+".all");
+    this.locationById = ProfileLocation.createAt(fullName + ".byId");
+    this.locationAll = ProfileLocation.createAt(fullName + ".all");
     this.profileBeanId = deploy.getProfileId();
     this.beanType = deploy.getBeanType();
     this.rootBeanType = PersistenceContextUtil.root(beanType);
@@ -601,7 +608,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
   /**
    * Create an entity bean that is used as a prototype/factory to create new instances.
    */
-  private EntityBean createPrototypeEntityBean(Class<T> beanType) {
+  protected EntityBean createPrototypeEntityBean(Class<T> beanType) {
     if (Modifier.isAbstract(beanType.getModifiers())) {
       return null;
     }
@@ -656,27 +663,29 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return properties;
   }
 
+  public BeanProperty propertyByIndex(int pos) {
+    return propertiesIndex[pos];
+  }
+
   /**
    * Initialise the Id properties first.
    * <p>
    * These properties need to be initialised prior to the association properties
    * as they are used to get the imported and exported properties.
    * </p>
-   *
-   * @param withHistoryTables map populated if @History is supported on this entity bean
    */
-  public void initialiseId(Map<String, String> withHistoryTables, Map<String, String> draftTables) {
+  public void initialiseId(BeanDescriptorInitContext initContext) {
 
     if (logger.isTraceEnabled()) {
       logger.trace("BeanDescriptor initialise " + fullName);
     }
 
     if (draftable) {
-      draftTables.put(baseTable, draftTable);
+      initContext.addDraft(baseTable, draftTable);
     }
     if (historySupport) {
       // add mapping (used to swap out baseTable for asOf queries)
-      withHistoryTables.put(baseTable, baseTableAsOf);
+      initContext.addHistory(baseTable, baseTableAsOf);
     }
 
     if (inheritInfo != null) {
@@ -686,28 +695,24 @@ public class BeanDescriptor<T> implements BeanType<T> {
     if (isEmbedded()) {
       // initialise all the properties
       for (BeanProperty prop : propertiesAll()) {
-        prop.initialise();
+        prop.initialise(initContext);
       }
     } else {
       // initialise just the Id properties
       if (idProperty != null) {
-        idProperty.initialise();
+        idProperty.initialise(initContext);
       }
     }
   }
 
   /**
    * Initialise the exported and imported parts for associated properties.
-   *
-   * @param asOfTableMap   the map of base tables to associated 'with history' tables
-   * @param asOfViewSuffix the suffix added to the table name to derive the 'with history' view name
-   * @param draftTableMap  the map of base tables to associated 'draft' tables.
    */
-  public void initialiseOther(Map<String, String> asOfTableMap, String asOfViewSuffix, Map<String, String> draftTableMap) {
+  public void initialiseOther(BeanDescriptorInitContext initContext) {
 
-    for (BeanPropertyAssocMany<?> aPropertiesManyToMany1 : propertiesManyToMany) {
+    for (BeanPropertyAssocMany<?> many : propertiesManyToMany) {
       // register associated draft table for M2M intersection
-      aPropertiesManyToMany1.registerDraftIntersectionTable(draftTableMap);
+      many.registerDraftIntersectionTable(initContext);
     }
 
     if (historySupport) {
@@ -717,8 +722,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
         // register associated history table for M2M intersection
         if (!aPropertiesManyToMany.isExcludedFromHistory()) {
           TableJoin intersectionTableJoin = aPropertiesManyToMany.getIntersectionTableJoin();
-          String intersectionTableName = intersectionTableJoin.getTable();
-          asOfTableMap.put(intersectionTableName, intersectionTableName + asOfViewSuffix);
+          initContext.addHistoryIntersection(intersectionTableJoin.getTable());
         }
       }
     }
@@ -727,14 +731,14 @@ public class BeanDescriptor<T> implements BeanType<T> {
       // initialise all the non-id properties
       for (BeanProperty prop : propertiesAll()) {
         if (!prop.isId()) {
-          prop.initialise();
+          prop.initialise(initContext);
         }
         prop.registerColumn(this, null);
       }
     }
 
     if (unidirectional != null) {
-      unidirectional.initialise();
+      unidirectional.initialise(initContext);
     }
 
     idBinder.initialise();
@@ -777,7 +781,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
 
     for (BeanProperty prop : propertiesNonTransient) {
       if (prop.isUnique()) {
-        propertiesUnique.add(new BeanProperty[] { prop });
+        propertiesUnique.add(new BeanProperty[]{prop});
       }
     }
     // convert unique columns to properties
@@ -799,7 +803,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
       if (propName == null) {
         return;
       }
-      props[i] = findBeanProperty(propName);
+      props[i] = findProperty(propName);
     }
     if (props.length == 1) {
       for (BeanProperty[] inserted : propertiesUnique) {
@@ -861,6 +865,16 @@ public class BeanDescriptor<T> implements BeanType<T> {
     }
   }
 
+  /**
+   * Bind all the property values to the SqlUpdate.
+   */
+  public void bindElementValue(SqlUpdate insert, Object value) {
+    EntityBean bean = (EntityBean) value;
+    for (BeanProperty property : propertiesBaseScalar) {
+      insert.setNextParameter(property.getValue(bean));
+    }
+  }
+
   /**
    * Return the ReadAuditLogger for logging read audit events.
    */
@@ -936,7 +950,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
       SpiJsonWriter jsonWriter = createJsonWriter(writer);
 
       jsonWriteForInsert(jsonWriter, request.getEntityBean());
-      jsonWriter.gen().flush();
+      jsonWriter.flush();
 
       return beanChange(ChangeType.INSERT, request.getBeanId(), writer.toString(), null);
 
@@ -950,6 +964,10 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return ebeanServer.jsonExtended().createJsonWriter(writer);
   }
 
+  SpiJsonReader createJsonReader(String json) {
+    return ebeanServer.jsonExtended().createJsonRead(this, json);
+  }
+
   /**
    * Populate the diff for inserts with flattened non-null property values.
    */
@@ -1016,7 +1034,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
 
     Object[] bindValues = idBinder.getBindValues(id);
     for (Object bindValue : bindValues) {
-      sqlDelete.addParameter(bindValue);
+      sqlDelete.setNextParameter(bindValue);
     }
 
     return sqlDelete;
@@ -1421,7 +1439,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
   @SuppressWarnings("unchecked")
   public void cacheBeanPutAll(Collection<?> beans) {
     if (!beans.isEmpty()) {
-      cacheHelp.beanPutAll((Collection<EntityBean>)beans);
+      cacheHelp.beanPutAll((Collection<EntityBean>) beans);
     }
   }
 
@@ -1639,6 +1657,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
   /**
    * Execute the postLoad if a BeanPostLoad exists for this bean.
    */
+  @Override
   public void postLoad(Object bean) {
     if (beanPostLoad != null) {
       beanPostLoad.postLoad(bean);
@@ -1705,7 +1724,15 @@ public class BeanDescriptor<T> implements BeanType<T> {
    * associated L2 bean caching.
    */
   public boolean isDeleteByStatement() {
-    return deleteRecurseSkippable && !isBeanCaching();
+    return persistListener == null
+      && persistController == null
+      && deleteRecurseSkippable && !isBeanCaching();
+  }
+
+  public boolean isDeleteByBulk() {
+    return persistListener == null
+      && persistController == null
+      && propertiesManyToMany.length == 0;
   }
 
   /**
@@ -1787,6 +1814,11 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return idBinder instanceof IdBinderSimple;
   }
 
+  @Override
+  public boolean hasId() {
+    return idProperty != null;
+  }
+
   /**
    * Return true if this type has a simple Id and the platform supports mutli-value binding.
    */
@@ -1847,6 +1879,9 @@ public class BeanDescriptor<T> implements BeanType<T> {
    * on first access (lazy load) or immediately (eager load)
    */
   public EntityBean createEntityBean(boolean isNew) {
+    if (prototypeEntityBean == null) {
+      throw new UnsupportedOperationException("cannot create entity bean for abstract entity " + getName());
+    }
     try {
       EntityBean bean = (EntityBean) prototypeEntityBean._ebean_newInstance();
 
@@ -1874,12 +1909,19 @@ public class BeanDescriptor<T> implements BeanType<T> {
   }
 
   /**
-   * Creates a new entitybean without invoking {@link BeanPostConstructListener#postCreate(Object)}
+   * Creates a new entity bean without invoking {@link BeanPostConstructListener#postCreate(Object)}
    */
   public EntityBean createEntityBean() {
     return createEntityBean(false);
   }
 
+  /**
+   * Create an entity bean for JSON marshalling (which differs for the element collection case).
+   */
+  public EntityBean createEntityBeanForJson() {
+    return createEntityBean();
+  }
+
   /**
    * Create a reference bean based on the id.
    */
@@ -1931,6 +1973,13 @@ public class BeanDescriptor<T> implements BeanType<T> {
   public T createReference(Object id, PersistenceContext pc) {
 
     try {
+      if (inheritInfo != null && !inheritInfo.isConcrete()) {
+        // we actually need to do a query because we don't know the type without the discriminator
+        // value, just select the id property and discriminator column (auto added)
+        DefaultOrmQuery<T> query = new DefaultOrmQuery<>(this, ebeanServer, ebeanServer.getExpressionFactory());
+        return query.select(getIdProperty().getName()).setId(id).findOne();
+      }
+
       EntityBean eb = createEntityBean();
       id = convertSetId(id, eb);
       EntityBeanIntercept ebi = eb._ebean_getIntercept();
@@ -1951,7 +2000,8 @@ public class BeanDescriptor<T> implements BeanType<T> {
    * Return the bean property traversing the object graph and taking into
    * account inheritance.
    */
-  public BeanProperty getBeanPropertyFromPath(String path) {
+  @Override
+  public BeanProperty findPropertyFromPath(String path) {
     BeanDescriptor<?> other = this;
     while (true) {
 
@@ -1983,7 +2033,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
       }
       String[] splitBegin = SplitName.splitBegin(path);
 
-      BeanProperty beanProperty = result.findBeanProperty(splitBegin[0]);
+      BeanProperty beanProperty = result.findProperty(splitBegin[0]);
       if (beanProperty instanceof BeanPropertyAssoc<?>) {
         BeanPropertyAssoc<?> assocProp = (BeanPropertyAssoc<?>) beanProperty;
         path = splitBegin[1];
@@ -2224,7 +2274,7 @@ public class BeanDescriptor<T> implements BeanType<T> {
 
   @Override
   public Property getProperty(String propName) {
-    return findBeanProperty(propName);
+    return findProperty(propName);
   }
 
   /**
@@ -2458,17 +2508,18 @@ public class BeanDescriptor<T> implements BeanType<T> {
   /**
    * Return a 'dynamic property' used to read a formula.
    */
-  private SqlTreeProperty findSqlTreeFormula(String formulaExpression) {
+  private STreeProperty findSqlTreeFormula(String formulaExpression) {
 
     return dynamicProperty.computeIfAbsent(formulaExpression, (formula) -> new FormulaPropertyPath(this, formula).build());
   }
 
   /**
    * Return a property that is part of the SQL tree.
-   *
+   * <p>
    * The property can be a dynamic formula or a well known bean property.
    */
-  public SqlTreeProperty findSqlTreeProperty(String propName) {
+  @Override
+  public STreeProperty findPropertyWithDynamic(String propName) {
     if (propName.indexOf('(') > -1) {
       return findSqlTreeFormula(propName);
     }
@@ -2482,7 +2533,8 @@ public class BeanDescriptor<T> implements BeanType<T> {
    * inheritance tree (not up).
    * </p>
    */
-  public BeanProperty findBeanProperty(String propName) {
+  @Override
+  public BeanProperty findProperty(String propName) {
     int basePos = propName.indexOf('.');
     if (basePos > -1) {
       // embedded property
@@ -2540,6 +2592,10 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return autoTunable;
   }
 
+  public boolean isElementType() {
+    return false;
+  }
+
   /**
    * Returns the Inheritance mapping information. This will be null if this type
    * of bean is not involved in any ORM inheritance mapping.
@@ -2809,6 +2865,41 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return draftableElement;
   }
 
+  @Override
+  public boolean isEmbeddedPath(String propertyPath) {
+    ElPropertyDeploy elProp = getElPropertyDeploy(propertyPath);
+    if (elProp == null) {
+      throw new PersistenceException("Invalid path " + propertyPath + " from " + getFullName());
+    }
+    return elProp.getBeanProperty().isEmbedded();
+  }
+
+  @Override
+  public ExtraJoin extraJoin(String propertyPath) {
+
+    ElPropertyValue elGetValue = getElGetValue(propertyPath);
+    if (elGetValue != null) {
+      BeanProperty beanProperty = elGetValue.getBeanProperty();
+      if (beanProperty instanceof BeanPropertyAssoc<?>) {
+        BeanPropertyAssoc<?> assocProp = (BeanPropertyAssoc<?>) beanProperty;
+        if (!assocProp.isEmbedded()) {
+          return new ExtraJoin(assocProp, elGetValue.containsMany());
+        }
+      }
+    }
+    return null;
+  }
+
+  @Override
+  public void inheritanceLoad(SqlBeanLoad sqlBeanLoad, STreeProperty property, DbReadContext ctx) {
+    BeanProperty p = getBeanProperty(property.getName());
+    if (p != null) {
+      p.load(sqlBeanLoad);
+    } else {
+      property.loadIgnore(ctx);
+    }
+  }
+
   public void setUnmappedJson(EntityBean bean, Map<String, Object> unmappedProperties) {
     if (unmappedJson != null) {
       unmappedJson.setValueIntercept(bean, unmappedProperties);
@@ -2933,16 +3024,6 @@ public class BeanDescriptor<T> implements BeanType<T> {
     return selectLastInsertedId;
   }
 
-  /**
-   * Return the TableJoins.
-   * <p>
-   * For properties mapped to secondary tables rather than the base table.
-   * </p>
-   */
-  public TableJoin[] tableJoins() {
-    return derivedTableJoins;
-  }
-
   @Override
   public Collection<? extends Property> allProperties() {
     return propertiesAll();
@@ -3131,6 +3212,26 @@ public class BeanDescriptor<T> implements BeanType<T> {
     }
   }
 
+  @Override
+  public STreeProperty[] propsBaseScalar() {
+    return propertiesBaseScalar;
+  }
+
+  @Override
+  public STreePropertyAssoc[] propsEmbedded() {
+    return propertiesEmbedded;
+  }
+
+  @Override
+  public STreePropertyAssocOne[] propsOne() {
+    return propertiesOne;
+  }
+
+  @Override
+  public STreePropertyAssocMany[] propsMany() {
+    return propertiesMany;
+  }
+
   /**
    * All the BeanPropertyAssocOne that are not embedded. These are effectively
    * joined beans. For ManyToOne and OneToOne associations.
@@ -3273,6 +3374,18 @@ public class BeanDescriptor<T> implements BeanType<T> {
     jsonHelp.jsonWriteDirtyProperties(writeJson, bean, dirtyProps);
   }
 
+  public void jsonWriteMapEntry(SpiJsonWriter ctx, Map.Entry<?, ?> entry) throws IOException {
+    throw new IllegalStateException("Unexpected - expect Element override");
+  }
+
+  public void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    throw new IllegalStateException("Unexpected - expect Element override");
+  }
+
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+    throw new IllegalStateException("Unexpected - expect Element override");
+  }
+
   public void jsonWrite(SpiJsonWriter writeJson, EntityBean bean) throws IOException {
     jsonHelp.jsonWrite(writeJson, bean, null);
   }
@@ -3285,11 +3398,11 @@ public class BeanDescriptor<T> implements BeanType<T> {
     jsonHelp.jsonWriteProperties(writeJson, bean);
   }
 
-  public T jsonRead(ReadJson jsonRead, String path) throws IOException {
+  public T jsonRead(SpiJsonReader jsonRead, String path) throws IOException {
     return jsonHelp.jsonRead(jsonRead, path);
   }
 
-  protected T jsonReadObject(ReadJson jsonRead, String path) throws IOException {
+  protected T jsonReadObject(SpiJsonReader jsonRead, String path) throws IOException {
     return jsonHelp.jsonReadObject(jsonRead, path);
   }
 

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorCacheHelp.java

@@ -20,6 +20,7 @@ import io.ebeaninternal.server.transaction.DefaultPersistenceContext;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -272,6 +273,11 @@ final class BeanDescriptorCacheHelp<T> {
    */
   boolean manyPropLoad(BeanPropertyAssocMany<?> many, BeanCollection<?> bc, Object parentId, Boolean readOnly) {
 
+    if (many.isElementCollection()) {
+      // held as part of the bean cache so skip
+			return false;
+    }
+
     CachedManyIds entry = manyPropGet(parentId, many.getName());
     if (entry == null) {
       // not in cache so return unsuccessful
@@ -298,9 +304,29 @@ final class BeanDescriptorCacheHelp<T> {
    */
   void manyPropPut(BeanPropertyAssocMany<?> many, Object details, Object parentId) {
 
-    CachedManyIds entry = createManyIds(many, details);
-    if (entry != null) {
-      cachePutManyIds(parentId, many.getName(), entry);
+    if (many.isElementCollection()) {
+      CachedBeanData data = (CachedBeanData) beanCache.get(parentId);
+      if (data != null) {
+        try {
+          // add as JSON to bean cache
+          String asJson = many.jsonWriteCollection(details);
+          Map<String,Object> changes = new HashMap<>();
+          changes.put(many.getName(), asJson);
+
+          CachedBeanData newData = data.update(changes, data.getVersion());
+          if (beanLog.isDebugEnabled()) {
+            beanLog.debug("   UPDATE {}({})  changes:{}", cacheName, parentId, changes);
+          }
+          beanCache.put(parentId, newData);
+        } catch (IOException e) {
+          logger.error("Error updating L2 cache", e);
+        }
+      }
+    } else {
+      CachedManyIds entry = createManyIds(many, details);
+      if (entry != null) {
+        cachePutManyIds(parentId, many.getName(), entry);
+      }
     }
   }
 
@@ -730,38 +756,17 @@ final class BeanDescriptorCacheHelp<T> {
     List<BeanPropertyAssocMany<?>> manyCollections = updateRequest.getUpdatedManyCollections();
     if (manyCollections != null) {
       for (BeanPropertyAssocMany<?> many : manyCollections) {
-        Object details = many.getValue(updateRequest.getEntityBean());
-        CachedManyIds entry = createManyIds(many, details);
-        if (entry != null) {
-          changeSet.addManyPut(desc, many.getName(), id, entry);
-        }
-      }
-    }
-
-    // check if the bean itself was updated
-    if (!updateRequest.isUpdatedManysOnly()) {
-
-      boolean updateNaturalKey = false;
-
-      Map<String, Object> changes = new LinkedHashMap<>();
-      EntityBean bean = updateRequest.getEntityBean();
-      boolean[] dirtyProperties = updateRequest.getDirtyProperties();
-      for (int i = 0; i < dirtyProperties.length; i++) {
-        if (dirtyProperties[i]) {
-          BeanProperty property = desc.propertiesIndex[i];
-          if (property.isCacheDataInclude()) {
-            Object val = property.getCacheDataValue(bean);
-            changes.put(property.getName(), val);
-            if (property.isNaturalKey()) {
-              updateNaturalKey = true;
-              changeSet.addNaturalKeyPut(desc, id, val);
-            }
+        if (!many.isElementCollection()) {
+          Object details = many.getValue(updateRequest.getEntityBean());
+          CachedManyIds entry = createManyIds(many, details);
+          if (entry != null) {
+            changeSet.addManyPut(desc, many.getName(), id, entry);
           }
         }
       }
-
-      changeSet.addBeanUpdate(desc, id, changes, updateNaturalKey, updateRequest.getVersion());
     }
+
+    updateRequest.addBeanUpdate(changeSet);
   }
 
   /**

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorElement.java

@@ -0,0 +1,49 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
+import io.ebeaninternal.server.type.ScalarType;
+
+import java.util.Arrays;
+
+/**
+ * Bean descriptor used with ElementCollection (where we don't have a mapped type/class).
+ * <p>
+ * This is somewhat a BeanDescriptor created 'on the fly' for a specific element collection property
+ * with a unidirectional property and mapping etc specific to the property (and not the type if embedded).
+ */
+abstract class BeanDescriptorElement<T> extends BeanDescriptor<T> {
+
+  final ElementHelp elementHelp;
+
+  BeanDescriptorElement(BeanDescriptorMap owner, DeployBeanDescriptor<T> deploy, ElementHelp elementHelp) {
+    super(owner, deploy);
+    this.elementHelp = elementHelp;
+  }
+
+  /**
+   * Find and return the first base scalar type (and we expect only 1).
+   */
+  ScalarType<Object> firstBaseScalarType() {
+    BeanProperty[] props = propertiesBaseScalar();
+    if (props.length != 1) {
+      throw new IllegalStateException("Expecting 1 property for element scalar but got " + Arrays.toString(props));
+    }
+    return props[0].getScalarType();
+  }
+
+  @Override
+  public boolean isElementType() {
+    return true;
+  }
+
+  /**
+   * Our entity beans used are somewhat fake ones (ElementEntityBean) such that we hold the unidirectional property
+   * value (foreign key) and the actual element collection value (scalar or embedded plus map key).
+   */
+  @Override
+  protected EntityBean createPrototypeEntityBean(Class<T> beanType) {
+    return new ElementEntityBean(properties);
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorElementEmbedded.java

@@ -0,0 +1,79 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.PersistenceIOException;
+import io.ebean.SqlUpdate;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
+
+import java.io.IOException;
+
+/**
+ * Bean descriptor used with element collection of list/set of embeddable.
+ */
+class BeanDescriptorElementEmbedded<T> extends BeanDescriptorElement<T> {
+
+  private final BeanPropertyAssocOne embeddedProperty;
+
+  private final EntityBean prototype;
+
+  private BeanDescriptor targetDescriptor;
+
+  BeanDescriptorElementEmbedded(BeanDescriptorMap owner, DeployBeanDescriptor<T> deploy, ElementHelp elementHelp) {
+    super(owner, deploy, elementHelp);
+    try {
+      this.prototype = (EntityBean) beanType.newInstance();
+    } catch (Exception e) {
+      throw new IllegalStateException("Unable to create entity bean prototype for "+beanType);
+    }
+    BeanPropertyAssocOne<?>[] embedded = propertiesEmbedded();
+    if (embedded.length == 1) {
+      embeddedProperty = embedded[0];
+    } else {
+      embeddedProperty = null;
+    }
+  }
+
+  @Override
+  public void initialiseOther(BeanDescriptorInitContext initContext) {
+    super.initialiseOther(initContext);
+    this.targetDescriptor = embeddedProperty.getTargetDescriptor();
+  }
+
+  @Override
+  public EntityBean createEntityBeanForJson() {
+    return (EntityBean)prototype._ebean_newInstance();
+  }
+
+  public void bindElementValue(SqlUpdate insert, Object value) {
+    targetDescriptor.bindElementValue(insert, value);
+  }
+
+  @Override
+  public void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    writeJsonElement(ctx, element);
+  }
+
+  @Override
+  public T jsonRead(SpiJsonReader jsonRead, String path) throws IOException {
+    return readJsonElement(jsonRead, path);
+  }
+
+  @SuppressWarnings("unchecked")
+  T readJsonElement(SpiJsonReader jsonRead, String path) throws IOException {
+    return (T)targetDescriptor.jsonRead(jsonRead, path);
+  }
+
+  void writeJsonElement(SpiJsonWriter ctx, Object element) {
+    try {
+      if (element == null) {
+        ctx.writeNull();
+      } else {
+        targetDescriptor.jsonWrite(ctx, (EntityBean)element);
+      }
+    } catch (IOException e) {
+      throw new PersistenceIOException(e);
+    }
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorElementEmbeddedMap.java

@@ -0,0 +1,84 @@
+package io.ebeaninternal.server.deploy;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
+import io.ebeaninternal.server.type.ScalarType;
+
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * Descriptor for element collection using Map with the value holding an embedded bean.
+ * <p>
+ * The expected limitation is that the key is a scalar type.
+ */
+class BeanDescriptorElementEmbeddedMap<T> extends BeanDescriptorElementEmbedded<T> {
+
+  private final ScalarType scalarTypeKey;
+
+  private final boolean stringKey;
+
+  BeanDescriptorElementEmbeddedMap(BeanDescriptorMap owner, DeployBeanDescriptor<T> deploy, ElementHelp elementHelp) {
+    super(owner, deploy, elementHelp);
+    this.scalarTypeKey = firstBaseScalarType();
+    this.stringKey = String.class.equals(scalarTypeKey.getType());
+  }
+
+  @Override
+  @SuppressWarnings("unchecked")
+  public void jsonWriteMapEntry(SpiJsonWriter ctx, Map.Entry<?, ?> entry) throws IOException {
+    ctx.writeStartObject();
+    if (stringKey) {
+      Object key = entry.getKey();
+      String keyName = (key == null) ? "null" : key.toString();
+      ctx.writeFieldName(keyName);
+      writeJsonElement(ctx, entry.getValue());
+    } else {
+      ctx.writeFieldName("key");
+      scalarTypeKey.jsonWrite(ctx.gen(), entry.getKey());
+      ctx.writeFieldName("value");
+      writeJsonElement(ctx, entry.getValue());
+    }
+    ctx.writeEndObject();
+  }
+
+  @Override
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+
+    JsonParser parser = readJson.getParser();
+    ElementCollector add = elementHelp.createCollector();
+    do {
+      JsonToken token = parser.nextToken();
+      if (token != JsonToken.START_OBJECT) {
+        break;
+      }
+      if (stringKey) {
+        String key = parser.nextFieldName();
+        parser.nextToken();
+        Object val = readJsonElement(readJson, null);
+        add.addKeyValue(key, val);
+
+      } else {
+        parser.nextFieldName();
+        Object key = scalarTypeKey.jsonRead(parser);
+
+        parser.nextFieldName();
+        Object val = readJsonElement(readJson, null);
+        add.addKeyValue(key, val);
+      }
+
+      token = parser.nextToken();
+      if (token != JsonToken.END_OBJECT) {
+        break;
+      }
+
+    } while (true);
+
+    return add.collection();
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorElementScalar.java

@@ -0,0 +1,56 @@
+package io.ebeaninternal.server.deploy;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+import io.ebean.PersistenceIOException;
+import io.ebean.SqlUpdate;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
+import io.ebeaninternal.server.type.ScalarType;
+
+import java.io.IOException;
+
+/**
+ * Bean descriptor used with element collection mapped to a list or set of scalar values.
+ */
+class BeanDescriptorElementScalar<T> extends BeanDescriptorElement<T> {
+
+  private final ScalarType<Object> scalarType;
+
+  BeanDescriptorElementScalar(BeanDescriptorMap owner, DeployBeanDescriptor<T> deploy, ElementHelp elementHelp) {
+    super(owner, deploy, elementHelp);
+    this.scalarType = firstBaseScalarType();
+  }
+
+  public void bindElementValue(SqlUpdate insert, Object value) {
+    insert.setNextParameter(value);
+  }
+
+  @Override
+  public void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    try {
+      scalarType.jsonWrite(ctx.gen(), element);
+    } catch (IOException e) {
+      throw new PersistenceIOException(e);
+    }
+  }
+
+  @Override
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+
+    JsonParser parser = readJson.getParser();
+    ElementCollector add = elementHelp.createCollector();
+    do {
+      JsonToken token = parser.nextToken();
+      if (JsonToken.VALUE_NULL == token || JsonToken.END_ARRAY == token) {
+        break;
+      }
+      add.addElement(scalarType.jsonRead(parser));
+    } while (true);
+
+    return add.collection();
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorElementScalarMap.java

@@ -0,0 +1,88 @@
+package io.ebeaninternal.server.deploy;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
+import io.ebeaninternal.server.type.ScalarType;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Map;
+
+/**
+ * Bean descriptor used with element collection mapped to Map where key and value are scalar types.
+ */
+class BeanDescriptorElementScalarMap<T> extends BeanDescriptorElement<T> {
+
+  private final ScalarType scalarTypeKey;
+  private final ScalarType scalarTypeVal;
+  private final boolean stringKey;
+
+  BeanDescriptorElementScalarMap(BeanDescriptorMap owner, DeployBeanDescriptor<T> deploy, ElementHelp elementHelp) {
+    super(owner, deploy, elementHelp);
+    BeanProperty[] props = propertiesNonTransient();
+    if (props.length != 2) {
+      throw new IllegalStateException("Expecting 2 properties for key and value but got " + Arrays.toString(props));
+    }
+    this.scalarTypeKey = props[0].getScalarType();
+    this.scalarTypeVal = props[1].getScalarType();
+    this.stringKey = String.class.equals(scalarTypeKey.getType());
+  }
+
+  @Override
+  @SuppressWarnings("unchecked")
+  public void jsonWriteMapEntry(SpiJsonWriter ctx, Map.Entry<?, ?> entry) throws IOException {
+    ctx.writeStartObject();
+    if (stringKey) {
+      Object key = entry.getKey();
+      String keyName = (key == null) ? "null" : key.toString();
+      ctx.writeFieldName(keyName);
+      scalarTypeVal.jsonWrite(ctx.gen(), entry.getValue());
+    } else {
+      ctx.writeFieldName("key");
+      scalarTypeKey.jsonWrite(ctx.gen(), entry.getKey());
+      ctx.writeFieldName("value");
+      scalarTypeVal.jsonWrite(ctx.gen(), entry.getValue());
+    }
+    ctx.writeEndObject();
+  }
+
+  @Override
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+
+    JsonParser parser = readJson.getParser();
+    ElementCollector add = elementHelp.createCollector();
+    do {
+      JsonToken token = parser.nextToken();
+      if (token != JsonToken.START_OBJECT) {
+        break;
+      }
+      if (stringKey) {
+        String key = parser.nextFieldName();
+        parser.nextToken();
+        Object val = scalarTypeVal.jsonRead(parser);
+        add.addKeyValue(key, val);
+
+      } else {
+        parser.nextFieldName();
+        Object key = scalarTypeKey.jsonRead(parser);
+
+        parser.nextFieldName();
+        Object val = scalarTypeVal.jsonRead(parser);
+        add.addKeyValue(key, val);
+      }
+
+      token = parser.nextToken();
+      if (token != JsonToken.END_OBJECT) {
+        break;
+      }
+
+    } while (true);
+
+    return add.collection();
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorInitContext.java

@@ -0,0 +1,32 @@
+package io.ebeaninternal.server.deploy;
+
+import java.util.Map;
+
+class BeanDescriptorInitContext {
+
+  private final Map<String, String> withHistoryTables;
+  private final Map<String, String> draftTables;
+  private final String asOfViewSuffix;
+
+  BeanDescriptorInitContext(Map<String, String> withHistoryTables, Map<String, String> draftTables, String asOfViewSuffix) {
+    this.withHistoryTables = withHistoryTables;
+    this.draftTables = draftTables;
+    this.asOfViewSuffix = asOfViewSuffix;
+  }
+
+  void addDraft(String baseTable, String draftTable) {
+    draftTables.put(baseTable, draftTable);
+  }
+
+  void addHistory(String baseTable, String baseTableAsOf) {
+    withHistoryTables.put(baseTable, baseTableAsOf);
+  }
+
+  void addHistoryIntersection(String intersectionTableName) {
+    withHistoryTables.put(intersectionTableName, intersectionTableName + asOfViewSuffix);
+  }
+
+  void addDraftIntersection(String intersectionPublishTable, String intersectionDraftTable) {
+    draftTables.put(intersectionPublishTable, intersectionDraftTable);
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorJsonHelp.java

@@ -5,8 +5,8 @@ import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
 import io.ebean.bean.EntityBean;
 import io.ebean.text.json.EJson;
-import io.ebeaninternal.server.text.json.ReadJson;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
 import java.io.IOException;
 import java.util.LinkedHashMap;
@@ -70,7 +70,7 @@ public class BeanDescriptorJsonHelp<T> {
   }
 
   @SuppressWarnings("unchecked")
-  public T jsonRead(ReadJson jsonRead, String path) throws IOException {
+  public T jsonRead(SpiJsonReader jsonRead, String path) throws IOException {
 
     JsonParser parser = jsonRead.getParser();
     //noinspection StatementWithEmptyBody
@@ -116,14 +116,14 @@ public class BeanDescriptorJsonHelp<T> {
     return (T) inheritInfo.readType(discValue).desc().jsonReadObject(jsonRead, path);
   }
 
-  protected T jsonReadObject(ReadJson readJson, String path) throws IOException {
+  protected T jsonReadObject(SpiJsonReader readJson, String path) throws IOException {
 
-    EntityBean bean = desc.createEntityBean();
+    EntityBean bean = desc.createEntityBeanForJson();
     return jsonReadProperties(readJson, bean, path);
   }
 
   @SuppressWarnings("unchecked")
-  protected T jsonReadProperties(ReadJson readJson, EntityBean bean, String path) throws IOException {
+  protected T jsonReadProperties(SpiJsonReader readJson, EntityBean bean, String path) throws IOException {
 
     if (path != null) {
       readJson.pushPath(path);

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorManager.java

@@ -56,7 +56,6 @@ import io.ebeaninternal.server.query.CQueryPlan;
 import io.ebeaninternal.server.type.ScalarType;
 import io.ebeaninternal.server.type.ScalarTypeInteger;
 import io.ebeaninternal.server.type.TypeManager;
-import io.ebeaninternal.xmlmapping.XmlMappingReader;
 import io.ebeaninternal.xmlmapping.model.XmAliasMapping;
 import io.ebeaninternal.xmlmapping.model.XmColumnMapping;
 import io.ebeaninternal.xmlmapping.model.XmEbean;
@@ -72,16 +71,12 @@ import javax.persistence.MappedSuperclass;
 import javax.persistence.PersistenceException;
 import javax.persistence.Transient;
 import javax.sql.DataSource;
-import java.io.IOException;
-import java.io.InputStream;
 import java.io.Serializable;
 import java.lang.reflect.Field;
 import java.lang.reflect.Modifier;
-import java.net.URL;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
-import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -184,8 +179,6 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
 
   private final BeanLifecycleAdapterFactory beanLifecycleAdapterFactory;
 
-  private final boolean eagerFetchLobs;
-
   private final String asOfViewSuffix;
 
   /**
@@ -215,12 +208,11 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     this.databasePlatform = serverConfig.getDatabasePlatform();
     this.multiValueBind = config.getMultiValueBind();
     this.idBinderFactory = new IdBinderFactory(databasePlatform.isIdInExpandedForm(), multiValueBind);
-    this.eagerFetchLobs = serverConfig.isEagerFetchLobs();
     this.queryPlanTTLSeconds = serverConfig.getQueryPlanTTLSeconds();
 
     this.asOfViewSuffix = getAsOfViewSuffix(databasePlatform, serverConfig);
     String versionsBetweenSuffix = getVersionsBetweenSuffix(databasePlatform, serverConfig);
-    this.readAnnotations = new ReadAnnotations(config.getGeneratedPropertyFactory(), asOfViewSuffix, versionsBetweenSuffix, serverConfig.isDisableL2Cache());
+    this.readAnnotations = new ReadAnnotations(config.getGeneratedPropertyFactory(), asOfViewSuffix, versionsBetweenSuffix, serverConfig);
     this.bootupClasses = config.getBootupClasses();
     this.createProperties = config.getDeployCreateProperties();
     this.namingConvention = serverConfig.getNamingConvention();
@@ -365,12 +357,12 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
   /**
    * Deploy returning the asOfTableMap (which is required by the SQL builders).
    */
-  public Map<String, String> deploy() {
+  public Map<String, String> deploy(List<XmEbean> mappings) {
 
     try {
       createListeners();
       readEntityDeploymentInitial();
-      readXmlMapping();
+      readXmlMapping(mappings);
       readEmbeddedDeployment();
       readEntityBeanTable();
       readEntityDeploymentAssociations();
@@ -401,30 +393,14 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     }
   }
 
-  private void readXmlMapping() {
+  private void readXmlMapping(List<XmEbean> mappings) {
+    ClassLoader classLoader = serverConfig.getClassLoadConfig().getClassLoader();
 
-    try {
-      ClassLoader classLoader = serverConfig.getClassLoadConfig().getClassLoader();
-
-      Enumeration<URL> resources = classLoader.getResources("ebean.xml");
-
-      List<XmEbean> mappings = new ArrayList<>();
-      while (resources.hasMoreElements()) {
-        URL url = resources.nextElement();
-        try (InputStream is = url.openStream()) {
-          mappings.add(XmlMappingReader.read(is));
-        }
+    for (XmEbean mapping : mappings) {
+      List<XmEntity> entityDeploy = mapping.getEntity();
+      for (XmEntity deploy : entityDeploy) {
+        readEntityMapping(classLoader, deploy);
       }
-
-      for (XmEbean mapping : mappings) {
-        List<XmEntity> entityDeploy = mapping.getEntity();
-        for (XmEntity deploy : entityDeploy) {
-          readEntityMapping(classLoader, deploy);
-        }
-      }
-
-    } catch (IOException e) {
-      throw new RuntimeException("Error reading ebean.xml", e);
     }
   }
 
@@ -575,12 +551,14 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     // we can initialise them which sorts out circular
     // dependencies for OneToMany and ManyToOne etc
 
+    BeanDescriptorInitContext initContext = new BeanDescriptorInitContext(asOfTableMap, draftTableMap, asOfViewSuffix);
+
     // PASS 1:
     // initialise the ID properties of all the beans
     // first (as they are needed to initialise the
     // associated properties in the second pass).
     for (BeanDescriptor<?> d : descMap.values()) {
-      d.initialiseId(asOfTableMap, draftTableMap);
+      d.initialiseId(initContext);
     }
 
     // PASS 2:
@@ -595,7 +573,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
       // also look for intersection tables with
       // associated history support and register them
       // into the asOfTableMap
-      d.initialiseOther(asOfTableMap, asOfViewSuffix, draftTableMap);
+      d.initialiseOther(initContext);
     }
 
     // PASS 4:
@@ -656,6 +634,13 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     return beanTableMap.get(type);
   }
 
+  /**
+   * Return a BeanTable for an ElementCollection.
+   */
+  public BeanTable createCollectionBeanTable(String fullTableName, Class<?> targetType) {
+    return new BeanTable(this, fullTableName, targetType);
+  }
+
   @SuppressWarnings("unchecked")
   public <T> BeanManager<T> getBeanManager(Class<T> entityType) {
 
@@ -1025,7 +1010,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
    * </p>
    */
   @SuppressWarnings({"unchecked", "rawtypes"})
-  private void makeUnidirectional(DeployBeanInfo<?> info, DeployBeanPropertyAssocMany<?> oneToMany) {
+  private void makeUnidirectional(DeployBeanPropertyAssocMany<?> oneToMany) {
 
     DeployBeanDescriptor<?> targetDesc = getTargetDescriptor(oneToMany);
 
@@ -1045,34 +1030,36 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     // mark this property as unidirectional
     oneToMany.setUnidirectional();
 
-    // create the 'shadow' unidirectional property
-    // which is put on the target descriptor
-    DeployBeanPropertyAssocOne<?> unidirectional = new DeployBeanPropertyAssocOne(targetDesc, owningType);
-    unidirectional.setUndirectionalShadow();
-    unidirectional.setNullable(false);
-    unidirectional.setDbRead(true);
-    unidirectional.setDbInsertable(true);
-    unidirectional.setDbUpdateable(false);
-
-    targetDesc.setUnidirectional(unidirectional);
-
     // specify table and table alias...
     BeanTable beanTable = getBeanTable(owningType);
-    unidirectional.setBeanTable(beanTable);
-    unidirectional.setName(beanTable.getBaseTable());
-
-    info.setBeanJoinType(unidirectional, true);
 
     // define the TableJoin
     DeployTableJoin oneToManyJoin = oneToMany.getTableJoin();
     if (!oneToManyJoin.hasJoinColumns()) {
       throw new RuntimeException("No join columns");
     }
+    createUnidirectional(targetDesc, owningType, beanTable, oneToManyJoin);
+  }
 
-    // inverse of the oneToManyJoin
-    DeployTableJoin unidirectionalJoin = unidirectional.getTableJoin();
-    unidirectionalJoin.setColumns(oneToManyJoin.columns(), true);
+  /**
+   * Create and add a Unidirectional property (for ElementCollection) which maps to the foreign key.
+   */
+  public <A> void createUnidirectional(DeployBeanDescriptor<?> targetDesc, Class<A> targetType, BeanTable beanTable, DeployTableJoin oneToManyJoin) {
 
+    // create the 'shadow' unidirectional property
+    // which is put on the target descriptor
+    DeployBeanPropertyAssocOne<A> unidirectional = new DeployBeanPropertyAssocOne<>(targetDesc, targetType);
+    unidirectional.setUndirectionalShadow();
+    unidirectional.setNullable(false);
+    unidirectional.setDbRead(true);
+    unidirectional.setDbInsertable(true);
+    unidirectional.setDbUpdateable(false);
+    unidirectional.setBeanTable(beanTable);
+    unidirectional.setName(beanTable.getBaseTable());
+    unidirectional.setJoinType(true);
+    unidirectional.setJoinColumns(oneToManyJoin.columns(), true);
+
+    targetDesc.setUnidirectional(unidirectional);
   }
 
   private void checkMappedByOneToOne(DeployBeanPropertyAssocOne<?> prop) {
@@ -1137,6 +1124,10 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
    */
   private void checkMappedByOneToMany(DeployBeanInfo<?> info, DeployBeanPropertyAssocMany<?> prop) {
 
+    if (prop.isElementCollection()) {
+      // skip mapping check
+      return;
+    }
     DeployBeanDescriptor<?> targetDesc = getTargetDescriptor(prop);
 
     if (targetDesc.isDraftableElement()) {
@@ -1159,7 +1150,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
 
       if (!findMappedBy(prop)) {
         if (!prop.isO2mJoinTable()) {
-          makeUnidirectional(info, prop);
+          makeUnidirectional(prop);
         }
         return;
       }
@@ -1311,7 +1302,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
 
     DeployBeanInfo<T> info = new DeployBeanInfo<>(deployUtil, desc);
 
-    readAnnotations.readInitial(info, eagerFetchLobs);
+    readAnnotations.readInitial(info);
     return info;
   }
 
@@ -1350,7 +1341,7 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
       // already assigned (So custom or UUID)
       return;
     }
-    if (desc.propertiesId().isEmpty()) {
+    if (desc.idProperty() == null) {
       // bean doesn't have an Id property
       if (desc.isBaseTableType() && desc.getBeanFinder() == null) {
         // expecting an id property
@@ -1491,6 +1482,9 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
   private boolean isPersistentField(DeployBeanProperty prop) {
 
     Field field = prop.getField();
+    if (field == null) {
+      return false;
+    }
     int modifiers = field.getModifiers();
     return !(Modifier.isStatic(modifiers) || Modifier.isTransient(modifiers)) && !field.isAnnotationPresent(Transient.class);
   }
@@ -1633,6 +1627,43 @@ public class BeanDescriptorManager implements BeanDescriptorMap {
     target.setPrimaryKeyJoin(inverseJoin);
   }
 
+  /**
+   * Create a DeployBeanDescriptor for an ElementCollection target.
+   */
+  public <A> DeployBeanDescriptor<A> createDeployDescriptor(Class<A> targetType) {
+    return new DeployBeanDescriptor<>(this, targetType, serverConfig);
+  }
+
+  /**
+   * Create a BeanDescriptor for an ElementCollection target.
+   */
+  public <A> BeanDescriptor<A> createElementDescriptor(DeployBeanDescriptor<A> elementDescriptor, ManyType manyType, boolean scalar) {
+
+    ElementHelp elementHelp = elementHelper(manyType);
+    if (manyType.isMap()) {
+      if (scalar) {
+        return new BeanDescriptorElementScalarMap<>(this, elementDescriptor, elementHelp);
+      } else {
+        return new BeanDescriptorElementEmbeddedMap<>(this, elementDescriptor, elementHelp);
+      }
+    }
+    if (scalar) {
+      return new BeanDescriptorElementScalar<>(this, elementDescriptor, elementHelp);
+    } else {
+      return new BeanDescriptorElementEmbedded<>(this, elementDescriptor, elementHelp);
+    }
+  }
+
+  private ElementHelp elementHelper(ManyType manyType) {
+    switch (manyType) {
+      case LIST: return new ElementHelpList();
+      case SET: return new ElementHelpSet();
+      case MAP: return new ElementHelpMap();
+      default:
+        throw new IllegalStateException("manyType unexpected "+manyType);
+    }
+  }
+
   public void visitMetrics(MetricVisitor visitor) {
     for (BeanDescriptor<?> desc : immutableDescriptorList) {
       desc.visitMetrics(visitor);

src/main/java/io/ebeaninternal/server/deploy/BeanLifecycleAdapterFactory.java

@@ -102,7 +102,6 @@ class BeanLifecycleAdapterFactory {
         postInserts.add(method);
         hasPersistMethods = true;
       }
-
       if (method.isAnnotationPresent(PreUpdate.class)) {
         preUpdates.add(method);
         hasPersistMethods = true;
@@ -111,7 +110,6 @@ class BeanLifecycleAdapterFactory {
         postUpdates.add(method);
         hasPersistMethods = true;
       }
-
       if (method.isAnnotationPresent(PreRemove.class)) {
         preDeletes.add(method);
         hasPersistMethods = true;
@@ -128,7 +126,6 @@ class BeanLifecycleAdapterFactory {
         postSoftDeletes.add(method);
         hasPersistMethods = true;
       }
-
       if (method.isAnnotationPresent(PostLoad.class)) {
         postLoads.add(method);
       }

src/main/java/io/ebeaninternal/server/deploy/BeanListHelp.java

@@ -5,10 +5,9 @@ import io.ebean.Query;
 import io.ebean.Transaction;
 import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollectionAdd;
-import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
 import io.ebean.common.BeanList;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -17,48 +16,20 @@ import java.util.List;
 /**
  * Helper object for dealing with Lists.
  */
-public final class BeanListHelp<T> extends BaseCollectionHelp<T> {
+public class BeanListHelp<T> extends BaseCollectionHelp<T> {
 
-  private final BeanPropertyAssocMany<T> many;
-  private final BeanDescriptor<T> targetDescriptor;
-  private final String propertyName;
-
-  private BeanCollectionLoader loader;
-
-  public BeanListHelp(BeanPropertyAssocMany<T> many) {
-    this.many = many;
-    this.targetDescriptor = many.getTargetDescriptor();
-    this.propertyName = many.getName();
+  BeanListHelp(BeanPropertyAssocMany<T> many) {
+    super(many);
   }
 
-  public BeanListHelp() {
-    this.many = null;
-    this.targetDescriptor = null;
-    this.propertyName = null;
-  }
-
-  @Override
-  public void setLoader(BeanCollectionLoader loader) {
-    this.loader = loader;
-  }
-
-  /**
-   * Internal add bypassing any modify listening.
-   */
-  @Override
-  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
-    if (withCheck) {
-      collection.internalAddWithCheck(bean);
-    } else {
-      collection.internalAdd(bean);
-    }
+  BeanListHelp() {
+    super();
   }
 
   @Override
   public BeanCollectionAdd getBeanCollectionAdd(Object bc, String mapKey) {
 
     if (bc instanceof BeanList<?>) {
-
       BeanList<?> bl = (BeanList<?>) bc;
       if (bl.getActualList() == null) {
         bl.setActualList(new ArrayList<>());
@@ -144,13 +115,7 @@ public final class BeanListHelp<T> extends BaseCollectionHelp<T> {
       list = (List<?>) collection;
     }
 
-    if (!list.isEmpty() || ctx.isIncludeEmpty()) {
-      ctx.beginAssocMany(name);
-      for (Object aList : list) {
-        targetDescriptor.jsonWrite(ctx, (EntityBean) aList);
-      }
-      ctx.endAssocMany();
-    }
+    jsonWriteCollection(ctx, name, list);
   }
 
 }

src/main/java/io/ebeaninternal/server/deploy/BeanListHelpElement.java

@@ -0,0 +1,30 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+
+/**
+ * Helper for element collection List.
+ */
+public class BeanListHelpElement<T> extends BeanListHelp<T> {
+
+  BeanListHelpElement(BeanPropertyAssocMany<T> many) {
+    super(many);
+  }
+
+  @Override
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    Object elementValue = bean._ebean_getField(0);
+    if (withCheck) {
+      collection.internalAddWithCheck(elementValue);
+    } else {
+      collection.internalAdd(elementValue);
+    }
+  }
+
+  @Override
+  void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    many.jsonWriteElementValue(ctx, element);
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/BeanMapHelp.java

@@ -5,10 +5,9 @@ import io.ebean.Query;
 import io.ebean.Transaction;
 import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollectionAdd;
-import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
 import io.ebean.common.BeanMap;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
 import java.io.IOException;
 import java.util.LinkedHashMap;
@@ -18,18 +17,17 @@ import java.util.Map.Entry;
 /**
  * Helper specifically for dealing with Maps.
  */
-public final class BeanMapHelp<T> extends BaseCollectionHelp<T> {
+public class BeanMapHelp<T> extends BaseCollectionHelp<T> {
 
   private final BeanPropertyAssocMany<T> many;
   private final BeanDescriptor<T> targetDescriptor;
   private final String propertyName;
   private final BeanProperty beanProperty;
-  private BeanCollectionLoader loader;
 
   /**
    * When created for a given query that will return a map.
    */
-  public BeanMapHelp(BeanDescriptor<T> targetDescriptor, String mapKey) {
+  BeanMapHelp(BeanDescriptor<T> targetDescriptor, String mapKey) {
     this.targetDescriptor = targetDescriptor;
     this.beanProperty = targetDescriptor.getBeanProperty(mapKey);
     this.many = null;
@@ -39,18 +37,13 @@ public final class BeanMapHelp<T> extends BaseCollectionHelp<T> {
   /**
    * When help is attached to a specific many property.
    */
-  public BeanMapHelp(BeanPropertyAssocMany<T> many) {
+  BeanMapHelp(BeanPropertyAssocMany<T> many) {
     this.many = many;
     this.targetDescriptor = many.getTargetDescriptor();
     this.propertyName = many.getName();
     this.beanProperty = targetDescriptor.getBeanProperty(many.getMapKey());
   }
 
-  @Override
-  public void setLoader(BeanCollectionLoader loader) {
-    this.loader = loader;
-  }
-
   @Override
   @SuppressWarnings("unchecked")
   public BeanCollectionAdd getBeanCollectionAdd(Object bc, String mapKey) {
@@ -182,8 +175,7 @@ public final class BeanMapHelp<T> extends BaseCollectionHelp<T> {
     if (!map.isEmpty() || ctx.isIncludeEmpty()) {
       ctx.beginAssocMany(name);
       for (Entry<?, ?> entry : map.entrySet()) {
-        //FIXME: json write map key ...
-        targetDescriptor.jsonWrite(ctx, (EntityBean) entry.getValue());
+        many.jsonWriteMapEntry(ctx, entry);
       }
       ctx.endAssocMany();
     }

src/main/java/io/ebeaninternal/server/deploy/BeanMapHelpElement.java

@@ -0,0 +1,31 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.bean.EntityBean;
+import io.ebean.common.BeanMap;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+
+public class BeanMapHelpElement<T> extends BeanMapHelp<T> {
+
+  BeanMapHelpElement(BeanPropertyAssocMany<T> many) {
+    super(many);
+  }
+
+  @Override
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    Object key = bean._ebean_getField(0);
+    Object val = bean._ebean_getField(1);
+
+    BeanMap<?, ?> map = ((BeanMap<?, ?>) collection);
+    if (withCheck) {
+      map.internalPutWithCheck(key, val);
+    } else {
+      map.internalPut(key, val);
+    }
+  }
+
+  @Override
+  void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    throw new IllegalStateException("not called");
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/BeanProperty.java

@@ -13,6 +13,8 @@ import io.ebean.util.SplitName;
 import io.ebean.util.StringHelper;
 import io.ebeaninternal.api.SpiExpressionRequest;
 import io.ebeaninternal.api.SpiQuery;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 import io.ebeaninternal.server.core.InternString;
 import io.ebeaninternal.server.deploy.generatedproperty.GeneratedProperty;
 import io.ebeaninternal.server.deploy.generatedproperty.GeneratedWhenCreated;
@@ -22,11 +24,9 @@ import io.ebeaninternal.server.el.ElPropertyChainBuilder;
 import io.ebeaninternal.server.el.ElPropertyValue;
 import io.ebeaninternal.server.properties.BeanPropertyGetter;
 import io.ebeaninternal.server.properties.BeanPropertySetter;
+import io.ebeaninternal.server.query.STreeProperty;
 import io.ebeaninternal.server.query.SqlBeanLoad;
 import io.ebeaninternal.server.query.SqlJoinType;
-import io.ebeaninternal.server.query.SqlTreeProperty;
-import io.ebeaninternal.server.text.json.ReadJson;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
 import io.ebeaninternal.server.type.DataBind;
 import io.ebeaninternal.server.type.ScalarType;
 import io.ebeaninternal.server.type.ScalarTypeBoolean;
@@ -56,15 +56,17 @@ import java.util.Set;
  * Description of a property of a bean. Includes its deployment information such
  * as database column mapping information.
  */
-public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty {
+public class BeanProperty implements ElPropertyValue, Property, STreeProperty {
 
   private static final Logger logger = LoggerFactory.getLogger(BeanProperty.class);
 
   /**
-   * Flag to mark this at part of the unique id.
+   * Flag to mark this is the id property.
    */
   final boolean id;
 
+  final boolean importedPrimaryKey;
+
   /**
    * Flag to make this as a dummy property for unidirecitonal relationships.
    */
@@ -274,6 +276,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     this.name = InternString.intern(deploy.getName());
     this.propertyIndex = deploy.getPropertyIndex();
     this.unidirectionalShadow = deploy.isUndirectionalShadow();
+    this.importedPrimaryKey = deploy.isImportedPrimaryKey();
     this.discriminator = deploy.isDiscriminator();
     this.localEncrypted = deploy.isLocalEncrypted();
     this.dbEncrypted = deploy.isDbEncrypted();
@@ -395,6 +398,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     this.softDeleteDbSet = source.softDeleteDbSet;
     this.softDeleteDbPredicate = source.softDeleteDbPredicate;
     this.fetchEager = source.fetchEager;
+    this.importedPrimaryKey = source.importedPrimaryKey;
     this.unidirectionalShadow = source.unidirectionalShadow;
     this.discriminator = source.discriminator;
     this.localEncrypted = source.isLocalEncrypted();
@@ -451,11 +455,10 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
    * initialise variables that can't be done in construction due to recursive
    * issues.
    */
-  public void initialise() {
+  public void initialise(BeanDescriptorInitContext initContext) {
     // do nothing for normal BeanProperty
     if (!isTransient && scalarType == null) {
-      String msg = "No ScalarType assigned to " + descriptor.getFullName() + "." + getName();
-      throw new RuntimeException(msg);
+      throw new RuntimeException("No ScalarType assigned to " + descriptor.getFullName() + "." + getName());
     }
   }
 
@@ -473,8 +476,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     this.deployOrder = deployOrder;
   }
 
-  public ElPropertyValue buildElPropertyValue(String propName, String remainder, ElPropertyChainBuilder chain,
-                                              boolean propertyDeploy) {
+  public ElPropertyValue buildElPropertyValue(String propName, String remainder, ElPropertyChainBuilder chain, boolean propertyDeploy) {
     return null;
   }
 
@@ -502,6 +504,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
   /**
    * Return true if this property is based on a formula.
    */
+  @Override
   public boolean isFormula() {
     return formula;
   }
@@ -527,6 +530,11 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     return descriptor.getEncryptKey(this);
   }
 
+  @Override
+  public String getEncryptKeyAsString() {
+    return getEncryptKey().getStringValue();
+  }
+
   public String getDecryptProperty(String propertyName) {
     return dbEncryptFunction.getDecryptSql(propertyName);
   }
@@ -549,6 +557,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
    * Add any extra joins required to support this property. Generally a no
    * operation except for a OneToOne exported.
    */
+  @Override
   public void appendFrom(DbSqlContext ctx, SqlJoinType joinType) {
     if (formula && sqlFormulaJoin != null) {
       ctx.appendFormulaJoin(sqlFormulaJoin, joinType);
@@ -573,6 +582,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     return aggregation != null;
   }
 
+  @Override
   public void appendSelect(DbSqlContext ctx, boolean subQuery) {
 
     if (aggregation != null) {
@@ -583,8 +593,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     } else if (!isTransient && !ignoreDraftOnlyProperty(ctx.isDraftQuery())) {
 
       if (secondaryTableJoin != null) {
-        String relativePrefix = ctx.getRelativePrefix(secondaryTableJoinPrefix);
-        ctx.pushTableAlias(relativePrefix);
+        ctx.pushTableAlias(ctx.getRelativePrefix(secondaryTableJoinPrefix));
       }
 
       if (dbEncrypted) {
@@ -611,14 +620,17 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     return owningType.isAssignableFrom(type);
   }
 
+  @Override
   public void loadIgnore(DbReadContext ctx) {
     scalarType.loadIgnore(ctx.getDataReader());
   }
 
+  @Override
   public void load(SqlBeanLoad sqlBeanLoad) {
     sqlBeanLoad.load(this);
   }
 
+  @Override
   public void buildRawSqlSelectChain(String prefix, List<String> selectChain) {
     if (prefix == null) {
       selectChain.add(name);
@@ -805,13 +817,6 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     setValue(bean, cacheData);
   }
 
-  /**
-   * Get the property value from a compound value type.
-   */
-  public Object getValueObject(Object bean) {
-    throw new RuntimeException("Expected to be called only on BeanPropertyCompoundScalar");
-  }
-
   @Override
   public Object getVal(Object bean) {
     return getValue((EntityBean) bean);
@@ -935,6 +940,13 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     return null;
   }
 
+  /**
+   * If true this bean maps to the primary key.
+   */
+  public boolean isImportedPrimaryKey() {
+    return importedPrimaryKey;
+  }
+
   @Override
   public boolean isAssocMany() {
     // Returns false - override in BeanPropertyAssocMany.
@@ -1358,6 +1370,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
   /**
    * Return true if this is included in the unique id.
    */
+  @Override
   public boolean isId() {
     return id;
   }
@@ -1366,6 +1379,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
    * Return true if this is an Embedded property. In this case it shares the
    * table and primary key of its owner object.
    */
+  @Override
   public boolean isEmbedded() {
     return embedded;
   }
@@ -1439,7 +1453,7 @@ public class BeanProperty implements ElPropertyValue, Property, SqlTreeProperty
     }
   }
 
-  public void jsonRead(ReadJson ctx, EntityBean bean) throws IOException {
+  public void jsonRead(SpiJsonReader ctx, EntityBean bean) throws IOException {
 
     JsonToken event = ctx.nextToken();
     if (JsonToken.VALUE_NULL == event) {

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssoc.java

@@ -1,10 +1,11 @@
 package io.ebeaninternal.server.deploy;
 
-import io.ebean.EbeanServer;
 import io.ebean.Query;
 import io.ebean.bean.EntityBean;
 import io.ebean.text.PathProperties;
 import io.ebean.util.SplitName;
+import io.ebeaninternal.api.SpiEbeanServer;
+import io.ebeaninternal.api.SpiQuery;
 import io.ebeaninternal.server.core.DefaultSqlUpdate;
 import io.ebeaninternal.server.core.InternString;
 import io.ebeaninternal.server.deploy.id.IdBinder;
@@ -15,7 +16,10 @@ import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssoc;
 import io.ebeaninternal.server.el.ElPropertyChainBuilder;
 import io.ebeaninternal.server.el.ElPropertyValue;
 import io.ebeaninternal.server.persist.MultiValueWrapper;
+import io.ebeaninternal.server.query.STreePropertyAssoc;
+import io.ebeaninternal.server.query.STreeType;
 import io.ebeaninternal.server.query.SqlJoinType;
+import io.ebeaninternal.server.querydefn.DefaultOrmQuery;
 import io.ebeanservice.docstore.api.mapping.DocMappingBuilder;
 import io.ebeanservice.docstore.api.mapping.DocPropertyMapping;
 import io.ebeanservice.docstore.api.mapping.DocPropertyType;
@@ -30,7 +34,7 @@ import java.util.List;
 /**
  * Abstract base for properties mapped to an associated bean, list, set or map.
  */
-public abstract class BeanPropertyAssoc<T> extends BeanProperty {
+public abstract class BeanPropertyAssoc<T> extends BeanProperty implements STreePropertyAssoc {
 
   private static final Logger logger = LoggerFactory.getLogger(BeanPropertyAssoc.class);
 
@@ -101,15 +105,18 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
    * Initialise post construction.
    */
   @Override
-  public void initialise() {
+  public void initialise(BeanDescriptorInitContext initContext) {
     // this *MUST* execute after the BeanDescriptor is
     // put into the map to stop infinite recursion
+    initialiseTargetDescriptor(initContext);
+  }
+
+  void initialiseTargetDescriptor(BeanDescriptorInitContext initContext) {
     targetDescriptor = descriptor.getBeanDescriptor(targetType);
     if (!isTransient) {
       targetIdBinder = targetDescriptor.getIdBinder();
       targetInheritInfo = targetDescriptor.getInheritInfo();
       saveRecurseSkippable = targetDescriptor.isSaveRecurseSkippable();
-
       if (!targetIdBinder.isComplexId()) {
         targetIdProperty = targetIdBinder.getIdProperty();
       }
@@ -142,6 +149,7 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
   /**
    * Add table join with table alias based on prefix.
    */
+  @Override
   public SqlJoinType addJoin(SqlJoinType joinType, String prefix, DbSqlContext ctx) {
     return tableJoin.addJoin(joinType, prefix, ctx);
   }
@@ -149,6 +157,7 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
   /**
    * Add table join with explicit table alias.
    */
+  @Override
   public SqlJoinType addJoin(SqlJoinType joinType, String a1, String a2, DbSqlContext ctx) {
     return tableJoin.addJoin(joinType, a1, a2, ctx);
   }
@@ -186,6 +195,29 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
     return targetDescriptor;
   }
 
+  SpiEbeanServer server() {
+    return descriptor.getEbeanServer();
+  }
+
+  /**
+   * Create a new query for the target type.
+   *
+   * We use target descriptor rather than target property type to support ElementCollection.
+   */
+  public SpiQuery<T> newQuery(SpiEbeanServer server) {
+    return new DefaultOrmQuery<>(targetDescriptor, server, server.getExpressionFactory());
+  }
+
+  @Override
+  public IdBinder getIdBinder() {
+    return descriptor.getIdBinder();
+  }
+
+  @Override
+  public STreeType target() {
+    return targetDescriptor;
+  }
+
   /**
    * Return true if the target side has soft delete.
    */
@@ -325,6 +357,13 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
     return tableJoin.columns().length <= 0 || tableJoin.columns()[0].isInsertable();
   }
 
+  /**
+   * Return the underlying BeanTable for this property.
+   */
+  public BeanTable getBeanTable() {
+    return beanTable;
+  }
+
   /**
    * return the join to use for the bean.
    */
@@ -440,19 +479,15 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
     }
   }
 
-  EbeanServer server() {
-    return getBeanDescriptor().getEbeanServer();
-  }
-
   void bindParentIds(DefaultSqlUpdate delete, List<Object> parentIds) {
 
     if (isExportedSimple()) {
-      delete.addParameter(new MultiValueWrapper(parentIds));
+      delete.setNextParameter(new MultiValueWrapper(parentIds));
     } else {
       // embedded ids etc
       List<Object> bindValues = flattenParentIds(parentIds);
       for (Object bindValue : bindValues) {
-        delete.addParameter(bindValue);
+        delete.setNextParameter(bindValue);
       }
     }
   }
@@ -460,12 +495,12 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
   void bindParentId(DefaultSqlUpdate sqlUpd, Object parentId) {
 
     if (isExportedSimple()) {
-      sqlUpd.addParameter(parentId);
+      sqlUpd.setNextParameter(parentId);
       return;
     }
     EntityBean parent = (EntityBean) parentId;
     for (ExportedProperty exportedProperty : exportedProperties) {
-      sqlUpd.addParameter(exportedProperty.getValue(parent));
+      sqlUpd.setNextParameter(exportedProperty.getValue(parent));
     }
   }
 
@@ -492,4 +527,26 @@ public abstract class BeanPropertyAssoc<T> extends BeanProperty {
   private boolean isExportedSimple() {
     return exportedProperties.length == 1;
   }
+
+  /**
+   * Find and return the exported property matching to this property.
+   */
+  ExportedProperty findMatch(boolean embedded, BeanProperty prop, String matchColumn, TableJoin tableJoin) {
+
+    String searchTable = tableJoin.getTable();
+
+    for (TableJoinColumn column : tableJoin.columns()) {
+      String matchTo = column.getLocalDbColumn();
+
+      if (matchColumn.equalsIgnoreCase(matchTo)) {
+        String foreignCol = column.getForeignDbColumn();
+        return new ExportedProperty(embedded, foreignCol, prop);
+      }
+    }
+
+    String msg = "Error with the Join on [" + getFullBeanName()
+      + "]. Could not find the matching foreign key for [" + matchColumn + "] in table[" + searchTable + "]?"
+      + " Perhaps using a @JoinColumn with the name/referencedColumnName attributes swapped?";
+    throw new PersistenceException(msg);
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocMany.java

@@ -1,7 +1,7 @@
 package io.ebeaninternal.server.deploy;
 
-import io.ebean.EbeanServer;
-import io.ebean.Query;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
 import io.ebean.SqlUpdate;
 import io.ebean.Transaction;
 import io.ebean.bean.BeanCollection;
@@ -9,22 +9,24 @@ import io.ebean.bean.BeanCollection.ModifyListenMode;
 import io.ebean.bean.BeanCollectionAdd;
 import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
+import io.ebean.bean.PersistenceContext;
 import io.ebean.text.PathProperties;
 import io.ebeaninternal.api.SpiExpressionRequest;
 import io.ebeaninternal.api.SpiQuery;
-import io.ebeaninternal.server.core.DefaultSqlUpdate;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 import io.ebeaninternal.server.deploy.id.ImportedId;
 import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocMany;
 import io.ebeaninternal.server.el.ElPropertyChainBuilder;
 import io.ebeaninternal.server.el.ElPropertyValue;
+import io.ebeaninternal.server.query.STreePropertyAssocMany;
 import io.ebeaninternal.server.query.SqlBeanLoad;
-import io.ebeaninternal.server.text.json.ReadJson;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.persistence.PersistenceException;
 import java.io.IOException;
+import java.io.StringWriter;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -35,7 +37,7 @@ import java.util.Map;
 /**
  * Property mapped to a List Set or Map.
  */
-public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
+public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> implements STreePropertyAssocMany {
 
   private static final Logger logger = LoggerFactory.getLogger(BeanPropertyAssocMany.class);
 
@@ -51,7 +53,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   /**
    * For ManyToMany this is the Inverse join used to build reference queries.
    */
-  private final TableJoin inverseJoin;
+  final TableJoin inverseJoin;
 
   /**
    * Flag to indicate that this is a unidirectional relationship.
@@ -70,6 +72,13 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
    */
   private final boolean manyToMany;
 
+  private final boolean elementCollection;
+
+  /**
+   * Descriptor for the 'target' when the property maps to an element collection.
+   */
+  BeanDescriptor<T> elementDescriptor;
+
   /**
    * Order by used when fetch joining the associated many.
    */
@@ -91,8 +100,6 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
 
   private BeanProperty mapKeyProperty;
 
-  private String exportedPropertyBindProto = "?";
-
   /**
    * Property on the 'child' bean that links back to the 'master'.
    */
@@ -106,9 +113,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
 
   private ImportedId importedId;
 
-  private String deleteByParentIdSql;
-
-  private String deleteByParentIdInSql;
+  private BeanPropertyAssocManySqlHelp<T> sqlHelp;
 
   /**
    * Create this property.
@@ -119,6 +124,8 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     this.o2mJoinTable = deploy.isO2mJoinTable();
     this.hasOrderColumn = deploy.hasOrderColumn();
     this.manyToMany = deploy.isManyToMany();
+    this.elementCollection = deploy.isElementCollection();
+    this.elementDescriptor = deploy.getElementDescriptor();
     this.manyType = deploy.getManyType();
     this.mapKey = deploy.getMapKey();
     this.fetchOrderBy = deploy.getFetchOrderBy();
@@ -136,13 +143,28 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   }
 
   @Override
-  public void initialise() {
-    super.initialise();
+  public void initialise(BeanDescriptorInitContext initContext) {
+    super.initialise(initContext);
+    initialiseAssocMany();
+    if (elementCollection) {
+      // initialise all non-id properties (we don't have an Id property)
+      elementDescriptor.initialiseOther(initContext);
+    }
+  }
 
+  @Override
+  void initialiseTargetDescriptor(BeanDescriptorInitContext initContext) {
+    if (elementCollection) {
+      targetDescriptor = elementDescriptor;
+    } else {
+      targetDescriptor = descriptor.getBeanDescriptor(targetType);
+    }
+  }
+
+  private void initialiseAssocMany() {
     if (!isTransient) {
       this.help = BeanCollectionHelpFactory.create(this);
-
-      if (hasJoinTable()) {
+      if (hasJoinTable() || elementCollection) {
         importedId = createImportedId(this, targetDescriptor, tableJoin);
 
       } else {
@@ -159,37 +181,21 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
       }
 
       exportedProperties = createExported();
+      this.sqlHelp = new BeanPropertyAssocManySqlHelp<>(this, exportedProperties);
+
       if (exportedProperties.length > 0) {
         embeddedExportedProperties = exportedProperties[0].isEmbedded();
-        exportedPropertyBindProto = deriveExportedPropertyBindProto();
-
         if (fetchOrderBy != null) {
-          // derive lazyFetchOrderBy
-          StringBuilder sb = new StringBuilder(50);
-          for (int i = 0; i < exportedProperties.length; i++) {
-            if (i > 0) {
-              sb.append(", ");
-            }
-            // these fk columns are either on the intersection (int_) or base table (t0)
-            String fkTableAlias = hasJoinTable() ? "int_" : "t0";
-            sb.append(fkTableAlias).append(".").append(exportedProperties[i].getForeignDbColumn());
-          }
-          sb.append(", ").append(fetchOrderBy);
-          lazyFetchOrderBy = sb.toString().trim();
+          lazyFetchOrderBy = sqlHelp.lazyFetchOrderBy(fetchOrderBy);
         }
       }
-
-      String delStmt;
-      if (hasJoinTable()) {
-        delStmt = "delete from " + inverseJoin.getTable() + " where ";
-      } else {
-        delStmt = "delete from " + targetDescriptor.getBaseTable() + " where ";
-      }
-      deleteByParentIdSql = delStmt + deriveWhereParentIdSql(false, "");
-      deleteByParentIdInSql = delStmt + deriveWhereParentIdSql(true, "");
     }
   }
 
+  String targetTable() {
+    return beanTable.getBaseTable();
+  }
+
   /**
    * Initialise after the target bean descriptors have been all set.
    */
@@ -295,44 +301,23 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
 
   public SqlUpdate deleteByParentId(Object parentId, List<Object> parentIdist) {
     if (parentId != null) {
-      return deleteByParentId(parentId);
+      return sqlHelp.deleteByParentId(parentId);
     } else {
-      return deleteByParentIdList(parentIdist);
+      return sqlHelp.deleteByParentIdList(parentIdist);
     }
   }
 
-  private SqlUpdate deleteByParentId(Object parentId) {
-    DefaultSqlUpdate sqlDelete = new DefaultSqlUpdate(deleteByParentIdSql);
-    bindParentId(sqlDelete, parentId);
-    return sqlDelete;
-  }
-
   /**
    * Find the Id's of detail beans given a parent Id or list of parent Id's.
    */
   public List<Object> findIdsByParentId(Object parentId, List<Object> parentIdList, Transaction t, List<Object> excludeDetailIds) {
     if (parentId != null) {
-      return findIdsByParentId(parentId, t, excludeDetailIds);
+      return sqlHelp.findIdsByParentId(parentId, t, excludeDetailIds);
     } else {
-      return findIdsByParentIdList(parentIdList, t, excludeDetailIds);
+      return sqlHelp.findIdsByParentIdList(parentIdList, t, excludeDetailIds);
     }
   }
 
-  private List<Object> findIdsByParentId(Object parentId, Transaction t, List<Object> excludeDetailIds) {
-
-    String rawWhere = deriveWhereParentIdSql(false, "");
-
-    EbeanServer server = server();
-    Query<?> q = server.find(getPropertyType());
-    bindParentIdEq(rawWhere, parentId, q);
-
-    if (excludeDetailIds != null && !excludeDetailIds.isEmpty()) {
-      q.where().not(q.getExpressionFactory().idIn(excludeDetailIds));
-    }
-
-    return server.findIds(q, t);
-  }
-
   /**
    * Exclude many properties from bean cache data.
    */
@@ -359,88 +344,10 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
       // assumes the ManyToOne property is included
       query.where().in(childMasterIdProperty, parentIds);
     } else {
-      addWhereParentIdIn(query, parentIds);
+      sqlHelp.addWhereParentIdIn(query, parentIds);
     }
   }
 
-  /**
-   * Add a where clause to the query for a given list of parent Id's.
-   */
-  private void addWhereParentIdIn(SpiQuery<?> query, List<Object> parentIds) {
-
-    String tableAlias = hasJoinTable() ? "int_." : "t0.";
-    if (hasJoinTable()) {
-      query.setM2MIncludeJoin(inverseJoin);
-    }
-    String rawWhere = deriveWhereParentIdSql(true, tableAlias);
-    String expr = descriptor.getParentIdInExpr(parentIds.size(), rawWhere);
-
-    bindParentIdsIn(expr, parentIds, query);
-  }
-
-  private List<Object> findIdsByParentIdList(List<Object> parentIds, Transaction t, List<Object> excludeDetailIds) {
-
-    String rawWhere = deriveWhereParentIdSql(true, "");
-    String inClause = buildInClauseBinding(parentIds.size(), exportedPropertyBindProto);
-
-    String expr = rawWhere + inClause;
-
-    EbeanServer server = descriptor.getEbeanServer();
-    Query<?> q = server.find(propertyType);
-    bindParentIdsIn(expr, parentIds, q);
-
-    if (excludeDetailIds != null && !excludeDetailIds.isEmpty()) {
-      q.where().not(q.getExpressionFactory().idIn(excludeDetailIds));
-    }
-
-    return server.findIds(q, t);
-  }
-
-  private SqlUpdate deleteByParentIdList(List<Object> parentIds) {
-
-    StringBuilder sb = new StringBuilder(100);
-    sb.append(deleteByParentIdInSql);
-    sb.append(buildInClauseBinding(parentIds.size(), exportedPropertyBindProto));
-
-    DefaultSqlUpdate delete = new DefaultSqlUpdate(sb.toString());
-    bindParentIds(delete, parentIds);
-    return delete;
-  }
-
-  private String deriveExportedPropertyBindProto() {
-    if (exportedProperties.length == 1) {
-      return "?";
-    }
-    StringBuilder sb = new StringBuilder();
-    sb.append("(");
-    for (int i = 0; i < exportedProperties.length; i++) {
-      if (i > 0) {
-        sb.append(",");
-      }
-      sb.append("?");
-    }
-    sb.append(")");
-    return sb.toString();
-  }
-
-  private String buildInClauseBinding(int size, String bindProto) {
-
-    if (descriptor.isSimpleId()) {
-      return descriptor.getIdBinder().getIdInValueExpr(false, size);
-    }
-    StringBuilder sb = new StringBuilder(10 + (size * (bindProto.length() + 1)));
-    sb.append(" in");
-    sb.append(" (");
-    for (int i = 0; i < size; i++) {
-      if (i > 0) {
-        sb.append(",");
-      }
-      sb.append(bindProto);
-    }
-    sb.append(") ");
-    return sb.toString();
-  }
-
   /**
    * Set the lazy load server to help create reference collections (that lazy
    * load on demand).
@@ -476,7 +383,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   }
 
   @Override
-  public Object readSet(DbReadContext ctx, EntityBean bean) throws SQLException {
+  public Object readSet(DbReadContext ctx, EntityBean bean) {
     return null;
   }
 
@@ -616,6 +523,10 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     return manyToMany;
   }
 
+  public boolean isElementCollection() {
+    return elementCollection;
+  }
+
   /**
    * ManyToMany only, join from local table to intersection table.
    */
@@ -705,30 +616,6 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     }
   }
 
-  private String deriveWhereParentIdSql(boolean inClause, String tableAlias) {
-
-    StringBuilder sb = new StringBuilder();
-
-    if (inClause) {
-      sb.append("(");
-    }
-    for (int i = 0; i < exportedProperties.length; i++) {
-      String fkColumn = exportedProperties[i].getForeignDbColumn();
-      if (i > 0) {
-        String s = inClause ? "," : " and ";
-        sb.append(s);
-      }
-      sb.append(tableAlias).append(fkColumn);
-      if (!inClause) {
-        sb.append("=? ");
-      }
-    }
-    if (inClause) {
-      sb.append(")");
-    }
-    return sb.toString();
-  }
-
   /**
    * Create the array of ExportedProperty used to build reference objects.
    */
@@ -741,12 +628,9 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     if (idProp != null && idProp.isEmbedded()) {
 
       BeanPropertyAssocOne<?> one = (BeanPropertyAssocOne<?>) idProp;
-      BeanDescriptor<?> targetDesc = one.getTargetDescriptor();
-      BeanProperty[] emIds = targetDesc.propertiesBaseScalar();
       try {
-        for (BeanProperty emId : emIds) {
-          ExportedProperty expProp = findMatch(true, emId);
-          list.add(expProp);
+        for (BeanProperty emId : one.getTargetDescriptor().propertiesBaseScalar()) {
+          list.add(findMatch(true, emId));
         }
       } catch (PersistenceException e) {
         // not found as individual scalar properties
@@ -755,8 +639,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
 
     } else {
       if (idProp != null) {
-        ExportedProperty expProp = findMatch(false, idProp);
-        list.add(expProp);
+        list.add(findMatch(false, idProp));
       }
     }
 
@@ -768,32 +651,12 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
    */
   private ExportedProperty findMatch(boolean embedded, BeanProperty prop) {
 
-    String matchColumn = prop.getDbColumn();
-
-    String searchTable;
-    TableJoinColumn[] columns;
     if (hasJoinTable()) {
       // look for column going to intersection
-      columns = intersectionJoin.columns();
-      searchTable = intersectionJoin.getTable();
-
+      return findMatch(embedded, prop, prop.getDbColumn(), intersectionJoin);
     } else {
-      columns = tableJoin.columns();
-      searchTable = tableJoin.getTable();
+      return findMatch(embedded, prop, prop.getDbColumn(), tableJoin);
     }
-    for (TableJoinColumn column : columns) {
-      String matchTo = column.getLocalDbColumn();
-
-      if (matchColumn.equalsIgnoreCase(matchTo)) {
-        String foreignCol = column.getForeignDbColumn();
-        return new ExportedProperty(embedded, foreignCol, prop);
-      }
-    }
-
-    String msg = "Error with the Join on [" + getFullBeanName()
-      + "]. Could not find the matching foreign key for [" + matchColumn + "] in table[" + searchTable + "]?"
-      + " Perhaps using a @JoinColumn with the name/referencedColumnName attributes swapped?";
-    throw new PersistenceException(msg);
   }
 
   /**
@@ -813,8 +676,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     Class<?> beanType = descriptor.getBeanType();
     BeanDescriptor<?> targetDesc = getTargetDescriptor();
 
-    BeanPropertyAssocOne<?>[] ones = targetDesc.propertiesOne();
-    for (BeanPropertyAssocOne<?> prop : ones) {
+    for (BeanPropertyAssocOne<?> prop : targetDesc.propertiesOne()) {
       if (mappedBy != null) {
         // match using mappedBy as property name
         if (mappedBy.equalsIgnoreCase(prop.getName())) {
@@ -880,9 +742,9 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   /**
    * Register the mapping of intersection table to associated draft table.
    */
-  public void registerDraftIntersectionTable(Map<String, String> draftTableMap) {
+  public void registerDraftIntersectionTable(BeanDescriptorInitContext initContext) {
     if (hasDraftIntersection()) {
-      draftTableMap.put(intersectionPublishTable, intersectionDraftTable);
+      initContext.addDraftIntersection(intersectionPublishTable, intersectionDraftTable);
     }
   }
 
@@ -928,7 +790,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
    * Skip JSON write value for ToMany property.
    */
   @Override
-  public void jsonWriteValue(SpiJsonWriter writeJson, Object value) throws IOException {
+  public void jsonWriteValue(SpiJsonWriter writeJson, Object value) {
     // do nothing, exclude ToMany properties
   }
 
@@ -946,7 +808,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
     if (value != null) {
       ctx.pushParentBeanMany(bean);
       if (help != null) {
-        help.jsonWrite(ctx, name, value, include != null);
+        jsonWriteCollection(ctx, name, value, include != null);
       } else {
         if (isTransient && targetDescriptor == null) {
           ctx.writeValueUsingObjectMapper(name, value);
@@ -962,7 +824,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   }
 
   @Override
-  public void jsonRead(ReadJson readJson, EntityBean parentBean) throws IOException {
+  public void jsonRead(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
     jsonHelp.jsonRead(readJson, parentBean);
   }
 
@@ -1030,4 +892,118 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   public boolean isIncludeCascadeDelete() {
     return cascadeInfo.isDelete() || o2mJoinTable || ModifyListenMode.REMOVALS == modifyListenMode;
   }
+
+  public String insertElementCollection() {
+    return sqlHelp.insertElementCollection();
+  }
+
+  public boolean isTargetDocStoreMapped() {
+    return targetDescriptor.isDocStoreMapped();
+  }
+
+  public BeanCollectionHelp<T> getHelp() {
+    return help;
+  }
+
+  public void jsonWriteMapEntry(SpiJsonWriter ctx, Map.Entry<?, ?> entry) throws IOException {
+    elementDescriptor.jsonWriteMapEntry(ctx, entry);
+  }
+
+  public void jsonWriteElementValue(SpiJsonWriter ctx, Object element) {
+    elementDescriptor.jsonWriteElement(ctx, element);
+  }
+
+  /**
+   * A Many (element collection) property in bean cache to held as JSON.
+   */
+  @Override
+  public void setCacheDataValue(EntityBean bean, Object cacheData, PersistenceContext context) {
+    try {
+      String asJson = (String) cacheData;
+      Object collection = jsonReadCollection(asJson);
+      setValue(bean, collection);
+    } catch (Exception e) {
+      logger.error("Error setting value from L2 cache", e);
+    }
+  }
+
+  @Override
+  public Object getCacheDataValue(EntityBean bean) {
+    try {
+      Object collection = getValue(bean);
+      if (collection == null) {
+        return null;
+      }
+      return jsonWriteCollection(collection);
+    } catch (Exception e) {
+      logger.error("Error building value element collection json for L2 cache", e);
+      return null;
+    }
+  }
+
+  /**
+   * Write the collection to JSON.
+   */
+  public String jsonWriteCollection(Object value) throws IOException {
+    StringWriter writer = new StringWriter(300);
+    SpiJsonWriter ctx = descriptor.createJsonWriter(writer);
+    help.jsonWrite(ctx, null, value, false);
+    ctx.flush();
+    return writer.toString();
+  }
+
+  /**
+   * Read the collection as JSON.
+   */
+  public Object jsonReadCollection(String json) throws IOException {
+    SpiJsonReader ctx = descriptor.createJsonReader(json);
+    JsonParser parser = ctx.getParser();
+    JsonToken event = parser.nextToken();
+    if (JsonToken.VALUE_NULL == event) {
+      return null;
+    }
+    return jsonReadCollection(ctx, null);
+  }
+
+  /**
+   * Write the collection to JSON.
+   */
+  public void jsonWriteCollection(SpiJsonWriter ctx, String name, Object value, boolean explicitInclude) throws IOException {
+    help.jsonWrite(ctx, name, value, explicitInclude);
+  }
+
+  /**
+   * Read the collection (JSON Array) containing entity beans.
+   */
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+
+    if (elementDescriptor != null && manyType.isMap()) {
+      return elementDescriptor.jsonReadCollection(readJson, parentBean);
+    }
+
+    BeanCollection<?> collection = createEmpty(parentBean);
+    BeanCollectionAdd add = getBeanCollectionAdd(collection, null);
+    do {
+      EntityBean detailBean = (EntityBean) targetDescriptor.jsonRead(readJson, name);
+      if (detailBean == null) {
+        // read the entire array
+        break;
+      }
+      add.addEntityBean(detailBean);
+
+      if (parentBean != null && childMasterProperty != null) {
+        // bind detail bean back to master via mappedBy property
+        childMasterProperty.setValue(detailBean, parentBean);
+      }
+    } while (true);
+
+    return collection;
+  }
+
+  /**
+   * Bind all the property values to the SqlUpdate.
+   */
+  public void bindElementValue(SqlUpdate insert, Object value) {
+    targetDescriptor.bindElementValue(insert, value);
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocManyJsonHelp.java

@@ -3,17 +3,15 @@ package io.ebeaninternal.server.deploy;
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
-import io.ebean.bean.BeanCollection;
-import io.ebean.bean.BeanCollectionAdd;
 import io.ebean.bean.EntityBean;
-import io.ebeaninternal.server.text.json.ReadJson;
+import io.ebeaninternal.api.json.SpiJsonReader;
 
 import java.io.IOException;
 
 /**
  * Help BeanPropertyAssocMany with JSON processing.
  */
-public class BeanPropertyAssocManyJsonHelp {
+class BeanPropertyAssocManyJsonHelp {
 
   /**
    * The associated many property.
@@ -28,7 +26,7 @@ public class BeanPropertyAssocManyJsonHelp {
   /**
    * Construct for the owning many property.
    */
-  public BeanPropertyAssocManyJsonHelp(BeanPropertyAssocMany<?> many) {
+  BeanPropertyAssocManyJsonHelp(BeanPropertyAssocMany<?> many) {
     this.many = many;
     boolean objectMapperPresent = many.getBeanDescriptor().getServerConfig().getClassLoadConfig().isJacksonObjectMapperPresent();
     this.jsonTransient = !objectMapperPresent ? null : new BeanPropertyAssocManyJsonTransient();
@@ -37,7 +35,7 @@ public class BeanPropertyAssocManyJsonHelp {
   /**
    * Read the JSON for this property.
    */
-  public void jsonRead(ReadJson readJson, EntityBean parentBean) throws IOException {
+  public void jsonRead(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
 
     if (!this.many.jsonDeserialize) {
       return;
@@ -57,29 +55,13 @@ public class BeanPropertyAssocManyJsonHelp {
       return;
     }
 
-    BeanCollection<?> collection = many.createEmpty(parentBean);
-    BeanCollectionAdd add = many.getBeanCollectionAdd(collection, null);
-    do {
-      EntityBean detailBean = (EntityBean) many.targetDescriptor.jsonRead(readJson, many.name);
-      if (detailBean == null) {
-        // read the entire array
-        break;
-      }
-      add.addEntityBean(detailBean);
-
-      if (parentBean != null && many.childMasterProperty != null) {
-        // bind detail bean back to master via mappedBy property
-        many.childMasterProperty.setValue(detailBean, parentBean);
-      }
-    } while (true);
-
-    many.setValue(parentBean, collection);
+    many.setValue(parentBean, many.jsonReadCollection(readJson, parentBean));
   }
 
   /**
    * Read a Transient property using Jackson ObjectMapper.
    */
-  private void jsonReadTransientUsingObjectMapper(ReadJson readJson, EntityBean parentBean) throws IOException {
+  private void jsonReadTransientUsingObjectMapper(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
 
     if (jsonTransient == null) {
       throw new IllegalStateException("Jackson ObjectMapper is required to read this Transient property " + many.getFullBeanName());

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocManyJsonTransient.java

@@ -6,7 +6,7 @@ import com.fasterxml.jackson.databind.type.CollectionType;
 import com.fasterxml.jackson.databind.type.MapType;
 import com.fasterxml.jackson.databind.type.TypeFactory;
 import io.ebean.bean.EntityBean;
-import io.ebeaninternal.server.text.json.ReadJson;
+import io.ebeaninternal.api.json.SpiJsonReader;
 
 import java.io.IOException;
 import java.util.LinkedHashMap;
@@ -14,12 +14,12 @@ import java.util.LinkedHashMap;
 /**
  * Helper used to read transient many properties using Jackson ObjectMapper.
  */
-public class BeanPropertyAssocManyJsonTransient {
+class BeanPropertyAssocManyJsonTransient {
 
   /**
    * Use Jackson ObjectMapper to read the transient 'many' property.
    */
-  public void jsonReadUsingObjectMapper(BeanPropertyAssocMany<?> many, ReadJson readJson, EntityBean parentBean) throws IOException {
+  void jsonReadUsingObjectMapper(BeanPropertyAssocMany<?> many, SpiJsonReader readJson, EntityBean parentBean) throws IOException {
 
     ObjectMapper mapper = readJson.getObjectMapper();
 

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocManySqlHelp.java

@@ -0,0 +1,258 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.SqlUpdate;
+import io.ebean.Transaction;
+import io.ebeaninternal.api.SpiEbeanServer;
+import io.ebeaninternal.api.SpiQuery;
+import io.ebeaninternal.dbmigration.model.visitor.BaseTablePropertyVisitor;
+import io.ebeaninternal.dbmigration.model.visitor.VisitAllUsing;
+import io.ebeaninternal.server.core.DefaultSqlUpdate;
+
+import java.util.List;
+
+class BeanPropertyAssocManySqlHelp<T> {
+
+  private final BeanPropertyAssocMany<T> many;
+  private final ExportedProperty[] exportedProperties;
+  private final boolean hasJoinTable;
+  private final BeanDescriptor<?> descriptor;
+  private final String exportedPropertyBindProto;
+  private final String deleteByParentIdSql;
+  private final String deleteByParentIdInSql;
+  private final String elementCollectionInsertSql;
+
+  BeanPropertyAssocManySqlHelp(BeanPropertyAssocMany<T> many, ExportedProperty[] exportedProperties) {
+    this.many = many;
+    this.exportedProperties = exportedProperties;
+    this.hasJoinTable = many.hasJoinTable();
+    this.descriptor = many.getBeanDescriptor();
+    this.exportedPropertyBindProto = deriveExportedPropertyBindProto();
+
+    String delStmt;
+    if (hasJoinTable) {
+      delStmt = "delete from " + many.inverseJoin.getTable() + " where ";
+    } else {
+      delStmt = "delete from " + many.targetTable() + " where ";
+    }
+    deleteByParentIdSql = delStmt + deriveWhereParentIdSql(false, "");
+    deleteByParentIdInSql = delStmt + deriveWhereParentIdSql(true, "");
+    if (many.isElementCollection()) {
+      elementCollectionInsertSql = elementCollectionInsert();
+    } else {
+      elementCollectionInsertSql = null;
+    }
+  }
+
+  private String elementCollectionInsert() {
+
+    StringBuilder sb = new StringBuilder(200);
+    sb.append("insert into ").append(many.targetTable()).append(" (");
+    append(sb, "", ",", "");
+
+    Cols cols = new Cols(sb);
+    VisitAllUsing.visitOne(many.targetDescriptor, cols);
+    sb.append(") values (");
+    appendBind(sb, exportedProperties.length, true);
+    appendBind(sb, cols.colCount, false);
+    sb.append(")");
+
+    return sb.toString();
+  }
+
+  public String insertElementCollection() {
+    return elementCollectionInsertSql;
+  }
+
+  private static class Cols extends BaseTablePropertyVisitor {
+
+    int colCount;
+
+    private final StringBuilder sb;
+
+    private Cols(StringBuilder sb) {
+      this.sb = sb;
+    }
+
+    @Override
+    public void visitEmbeddedScalar(BeanProperty p, BeanPropertyAssocOne<?> embedded) {
+      sb.append(",").append(p.getDbColumn());
+      colCount++;
+    }
+
+    @Override
+    public void visitOneImported(BeanPropertyAssocOne<?> p) {
+
+    }
+
+    @Override
+    public void visitScalar(BeanProperty p) {
+      sb.append(",").append(p.getDbColumn());
+      colCount++;
+    }
+
+    @Override
+    public void visitEnd() {
+
+    }
+  }
+
+  String lazyFetchOrderBy(String fetchOrderBy) {
+
+    // derive lazyFetchOrderBy
+    StringBuilder sb = new StringBuilder(50);
+    for (int i = 0; i < exportedProperties.length; i++) {
+      if (i > 0) {
+        sb.append(", ");
+      }
+      // these fk columns are either on the intersection (int_) or base table (t0)
+      String fkTableAlias = hasJoinTable ? "int_" : "t0";
+      sb.append(fkTableAlias).append(".").append(exportedProperties[i].getForeignDbColumn());
+    }
+    sb.append(", ").append(fetchOrderBy);
+    return sb.toString().trim();
+  }
+
+  /**
+   * Add a where clause to the query for a given list of parent Id's.
+   */
+  void addWhereParentIdIn(SpiQuery<?> query, List<Object> parentIds) {
+
+    String tableAlias = hasJoinTable ? "int_." : "t0.";
+    if (hasJoinTable) {
+      query.setM2MIncludeJoin(many.inverseJoin);
+    }
+    String rawWhere = deriveWhereParentIdSql(true, tableAlias);
+    String expr = descriptor.getParentIdInExpr(parentIds.size(), rawWhere);
+
+    many.bindParentIdsIn(expr, parentIds, query);
+  }
+
+  List<Object> findIdsByParentId(Object parentId, Transaction t, List<Object> excludeDetailIds) {
+
+    String rawWhere = deriveWhereParentIdSql(false, "");
+
+    SpiEbeanServer server = descriptor.getEbeanServer();
+    SpiQuery<?> q = many.newQuery(server);
+    many.bindParentIdEq(rawWhere, parentId, q);
+
+    if (excludeDetailIds != null && !excludeDetailIds.isEmpty()) {
+      q.where().not(q.getExpressionFactory().idIn(excludeDetailIds));
+    }
+
+    return server.findIds(q, t);
+  }
+
+  List<Object> findIdsByParentIdList(List<Object> parentIds, Transaction t, List<Object> excludeDetailIds) {
+
+    String rawWhere = deriveWhereParentIdSql(true, "");
+    String inClause = buildInClauseBinding(parentIds.size(), exportedPropertyBindProto);
+
+    String expr = rawWhere + inClause;
+
+    SpiEbeanServer server = descriptor.getEbeanServer();
+    SpiQuery<?> q = many.newQuery(server);
+    //Query<?> q = server.find(propertyType);
+    many.bindParentIdsIn(expr, parentIds, q);
+
+    if (excludeDetailIds != null && !excludeDetailIds.isEmpty()) {
+      q.where().not(q.getExpressionFactory().idIn(excludeDetailIds));
+    }
+
+    return server.findIds(q, t);
+  }
+
+  SqlUpdate deleteByParentId(Object parentId) {
+    DefaultSqlUpdate sqlDelete = new DefaultSqlUpdate(deleteByParentIdSql);
+    many.bindParentId(sqlDelete, parentId);
+    return sqlDelete;
+  }
+
+  SqlUpdate deleteByParentIdList(List<Object> parentIds) {
+
+    StringBuilder sb = new StringBuilder(100);
+    sb.append(deleteByParentIdInSql);
+    sb.append(buildInClauseBinding(parentIds.size(), exportedPropertyBindProto));
+
+    DefaultSqlUpdate delete = new DefaultSqlUpdate(sb.toString());
+    many.bindParentIds(delete, parentIds);
+    return delete;
+  }
+
+  private void appendBind(StringBuilder sb, int count, boolean skipComma) {
+    for (int i = 0; i < count; i++) {
+      if (!skipComma || i > 0) {
+        sb.append(",");
+      }
+      sb.append("?");
+    }
+  }
+
+  private void append(StringBuilder sb, String tableAlias, String prefix, String suffix) {
+    for (int i = 0; i < exportedProperties.length; i++) {
+      String fkColumn = exportedProperties[i].getForeignDbColumn();
+      if (i > 0) {
+        sb.append(prefix);
+      }
+      sb.append(tableAlias).append(fkColumn);
+      sb.append(suffix);
+    }
+  }
+  private String deriveWhereParentIdSql(boolean inClause, String tableAlias) {
+
+    StringBuilder sb = new StringBuilder();
+
+    if (inClause) {
+      sb.append("(");
+    }
+    for (int i = 0; i < exportedProperties.length; i++) {
+      String fkColumn = exportedProperties[i].getForeignDbColumn();
+      if (i > 0) {
+        String s = inClause ? "," : " and ";
+        sb.append(s);
+      }
+      sb.append(tableAlias).append(fkColumn);
+      if (!inClause) {
+        sb.append("=? ");
+      }
+    }
+    if (inClause) {
+      sb.append(")");
+    }
+    return sb.toString();
+  }
+
+  private String buildInClauseBinding(int size, String bindProto) {
+
+    if (descriptor.isSimpleId()) {
+      return descriptor.getIdBinder().getIdInValueExpr(false, size);
+    }
+    StringBuilder sb = new StringBuilder(10 + (size * (bindProto.length() + 1)));
+    sb.append(" in");
+    sb.append(" (");
+    for (int i = 0; i < size; i++) {
+      if (i > 0) {
+        sb.append(",");
+      }
+      sb.append(bindProto);
+    }
+    sb.append(") ");
+    return sb.toString();
+  }
+
+  private String deriveExportedPropertyBindProto() {
+    if (exportedProperties.length == 1) {
+      return "?";
+    }
+    StringBuilder sb = new StringBuilder();
+    sb.append("(");
+    for (int i = 0; i < exportedProperties.length; i++) {
+      if (i > 0) {
+        sb.append(",");
+      }
+      sb.append("?");
+    }
+    sb.append(")");
+    return sb.toString();
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java

@@ -9,6 +9,8 @@ import io.ebean.bean.EntityBean;
 import io.ebean.bean.PersistenceContext;
 import io.ebean.util.SplitName;
 import io.ebeaninternal.api.SpiQuery;
+import io.ebeaninternal.api.json.SpiJsonReader;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 import io.ebeaninternal.server.cache.CacheChangeSet;
 import io.ebeaninternal.server.cache.CachedBeanData;
 import io.ebeaninternal.server.core.DefaultSqlUpdate;
@@ -16,10 +18,10 @@ import io.ebeaninternal.server.deploy.id.ImportedId;
 import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
 import io.ebeaninternal.server.el.ElPropertyChainBuilder;
 import io.ebeaninternal.server.el.ElPropertyValue;
+import io.ebeaninternal.server.query.STreePropertyAssocOne;
 import io.ebeaninternal.server.query.SqlBeanLoad;
 import io.ebeaninternal.server.query.SqlJoinType;
-import io.ebeaninternal.server.text.json.ReadJson;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.server.type.ScalarType;
 
 import javax.persistence.PersistenceException;
 import java.io.IOException;
@@ -32,7 +34,7 @@ import java.util.Map;
 /**
  * Property mapped to a joined bean.
  */
-public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
+public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> implements STreePropertyAssocOne {
 
   private final boolean oneToOne;
 
@@ -40,8 +42,6 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
 
   private final boolean orphanRemoval;
 
-  private final boolean importedPrimaryKey;
-
   private final boolean primaryKeyExport;
 
   private final PropertyForeignKey foreignKey;
@@ -76,7 +76,6 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
 
     foreignKey = deploy.getForeignKey();
     primaryKeyExport = deploy.isPrimaryKeyExport();
-    importedPrimaryKey = deploy.isImportedPrimaryKey();
     oneToOne = deploy.isOneToOne();
     oneToOneExported = deploy.isOneToOneExported();
     orphanRemoval = deploy.isOrphanRemoval();
@@ -97,8 +96,12 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
   }
 
   @Override
-  public void initialise() {
-    super.initialise();
+  public void initialise(BeanDescriptorInitContext initContext) {
+    super.initialise(initContext);
+    initialiseAssocOne();
+  }
+
+  private void initialiseAssocOne() {
     localHelp = createHelp(embedded, oneToOneExported);
 
     if (!isTransient) {
@@ -307,6 +310,10 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
         String discProperty = prefix + "." + discriminatorColumn;
         selectChain.add(discProperty);
       }
+      if (targetIdBinder == null) {
+        throw new IllegalStateException("No Id binding property for " + getFullBeanName()
+          + ". Probably a missing @OneToOne mapping annotation on this relationship?");
+      }
       targetIdBinder.buildRawSqlSelectChain(prefix, selectChain);
 
     } else {
@@ -346,13 +353,6 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
     return orphanRemoval;
   }
 
-  /**
-   * If true this bean maps to the primary key.
-   */
-  public boolean isImportedPrimaryKey() {
-    return importedPrimaryKey;
-  }
-
   @Override
   public void diff(String prefix, Map<String, ValuePair> map, EntityBean newBean, EntityBean oldBean) {
 
@@ -427,6 +427,11 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
     }
   }
 
+  @Override
+  public ScalarType<?> getIdScalarType() {
+    return targetDescriptor.getIdProperty().getScalarType();
+  }
+
   /**
    * Return the Id values from the given bean.
    */
@@ -549,24 +554,7 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
    */
   private ExportedProperty findMatch(boolean embeddedProp, BeanProperty prop) {
 
-    String matchColumn = prop.getDbColumn();
-
-    String searchTable = tableJoin.getTable();
-    TableJoinColumn[] columns = tableJoin.columns();
-
-    for (TableJoinColumn column : columns) {
-      String matchTo = column.getLocalDbColumn();
-
-      if (matchColumn.equalsIgnoreCase(matchTo)) {
-        String foreignCol = column.getForeignDbColumn();
-        return new ExportedProperty(embeddedProp, foreignCol, prop);
-      }
-    }
-
-    String msg = "Error with the Join on [" + getFullBeanName()
-      + "]. Could not find the matching foreign key for [" + matchColumn + "] in table[" + searchTable + "]?"
-      + " Perhaps using a @JoinColumn with the name/referencedColumnName attributes swapped?";
-    throw new PersistenceException(msg);
+    return findMatch(embeddedProp, prop, prop.getDbColumn(), tableJoin);
   }
 
 
@@ -626,6 +614,14 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
     }
   }
 
+  @Override
+  public void setValueIntercept(EntityBean bean, Object value) {
+    super.setValueIntercept(bean, value);
+    if (embedded && value instanceof EntityBean) {
+      setEmbeddedOwner(bean, value);
+    }
+  }
+
   /**
    * For embedded bean set the owner and all properties to be loaded (recursively).
    */
@@ -638,18 +634,10 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
     }
   }
 
-  private void setEmbeddedOwner(EntityBean bean, Object value) {
+  void setEmbeddedOwner(EntityBean bean, Object value) {
     ((EntityBean) value)._ebean_getIntercept().setEmbeddedOwner(bean, propertyIndex);
   }
 
-  @Override
-  public void setValueIntercept(EntityBean bean, Object value) {
-    super.setValueIntercept(bean, value);
-    if (embedded && value instanceof EntityBean) {
-      setEmbeddedOwner(bean, value);
-    }
-  }
-
   @Override
   public void loadIgnore(DbReadContext ctx) {
     localHelp.loadIgnore(ctx);
@@ -708,10 +696,10 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
       if (embedded) {
         writeJson.writeFieldName(name);
         BeanDescriptor<?> refDesc = descriptor.getBeanDescriptor(value.getClass());
-        refDesc.jsonWriteForInsert(writeJson, (EntityBean)value);
+        refDesc.jsonWriteForInsert(writeJson, (EntityBean) value);
 
       } else {
-        jsonWriteTargetId(writeJson, (EntityBean)value);
+        jsonWriteTargetId(writeJson, (EntityBean) value);
       }
     }
   }
@@ -756,7 +744,7 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> {
   }
 
   @Override
-  public void jsonRead(ReadJson readJson, EntityBean bean) throws IOException {
+  public void jsonRead(SpiJsonReader readJson, EntityBean bean) throws IOException {
     if (jsonDeserialize && targetDescriptor != null) {
       T assocBean = targetDescriptor.jsonRead(readJson, name);
       setValue(bean, assocBean);

src/main/java/io/ebeaninternal/server/deploy/BeanPropertyIdClass.java

@@ -0,0 +1,35 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
+
+/**
+ * Bean property for an IdClass embeddedId.
+ */
+public class BeanPropertyIdClass extends BeanPropertyAssocOne {
+
+  public BeanPropertyIdClass(BeanDescriptorMap owner, BeanDescriptor descriptor, DeployBeanPropertyAssocOne deploy) {
+    super(owner, descriptor, deploy);
+  }
+
+  @Override
+  public void setValue(EntityBean bean, Object value) {
+    bean._ebean_getIntercept().setOwnerId(value);
+  }
+
+  @Override
+  public void setValueIntercept(EntityBean bean, Object value) {
+    bean._ebean_getIntercept().setOwnerId(value);
+  }
+
+  @Override
+  public Object getValue(EntityBean bean) {
+    return bean._ebean_getIntercept().getOwnerId();
+  }
+
+  @Override
+  public Object getValueIntercept(EntityBean bean) {
+    return bean._ebean_getIntercept().getOwnerId();
+  }
+
+}

src/main/java/io/ebeaninternal/server/deploy/BeanPropertySimpleCollection.java

@@ -1,11 +1,25 @@
 package io.ebeaninternal.server.deploy;
 
+import io.ebean.SqlUpdate;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonReader;
 import io.ebeaninternal.server.deploy.meta.DeployBeanPropertySimpleCollection;
 
+import java.io.IOException;
+
 public class BeanPropertySimpleCollection<T> extends BeanPropertyAssocMany<T> {
 
   public BeanPropertySimpleCollection(BeanDescriptor<?> descriptor, DeployBeanPropertySimpleCollection<T> deploy) {
     super(descriptor, deploy);
   }
 
+  @Override
+  public void bindElementValue(SqlUpdate insert, Object value) {
+    insert.setNextParameter(value);
+  }
+
+  @Override
+  public Object jsonReadCollection(SpiJsonReader readJson, EntityBean parentBean) throws IOException {
+    return elementDescriptor.jsonReadCollection(readJson, parentBean);
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/BeanSetHelp.java

@@ -5,10 +5,9 @@ import io.ebean.Query;
 import io.ebean.Transaction;
 import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollectionAdd;
-import io.ebean.bean.BeanCollectionLoader;
 import io.ebean.bean.EntityBean;
 import io.ebean.common.BeanSet;
-import io.ebeaninternal.server.text.json.SpiJsonWriter;
+import io.ebeaninternal.api.json.SpiJsonWriter;
 
 import java.io.IOException;
 import java.util.LinkedHashSet;
@@ -17,34 +16,20 @@ import java.util.Set;
 /**
  * Helper specifically for dealing with Sets.
  */
-public final class BeanSetHelp<T> extends BaseCollectionHelp<T> {
-
-  private final BeanPropertyAssocMany<T> many;
-  private final BeanDescriptor<T> targetDescriptor;
-  private final String propertyName;
-  private BeanCollectionLoader loader;
+public class BeanSetHelp<T> extends BaseCollectionHelp<T> {
 
   /**
    * When attached to a specific many property.
    */
-  public BeanSetHelp(BeanPropertyAssocMany<T> many) {
-    this.many = many;
-    this.targetDescriptor = many.getTargetDescriptor();
-    this.propertyName = many.getName();
+  BeanSetHelp(BeanPropertyAssocMany<T> many) {
+    super(many);
   }
 
   /**
    * For a query that returns a set.
    */
-  public BeanSetHelp() {
-    this.many = null;
-    this.targetDescriptor = null;
-    this.propertyName = null;
-  }
-
-  @Override
-  public void setLoader(BeanCollectionLoader loader) {
-    this.loader = loader;
+  BeanSetHelp() {
+    super();
   }
 
   @Override
@@ -61,15 +46,6 @@ public final class BeanSetHelp<T> extends BaseCollectionHelp<T> {
     }
   }
 
-  @Override
-  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
-    if (withCheck) {
-      collection.internalAddWithCheck(bean);
-    } else {
-      collection.internalAdd(bean);
-    }
-  }
-
   @Override
   public BeanCollection<T> createEmptyNoParent() {
     return new BeanSet<>();
@@ -142,13 +118,6 @@ public final class BeanSetHelp<T> extends BaseCollectionHelp<T> {
     } else {
       set = (Set<?>) collection;
     }
-
-    if (!set.isEmpty() || ctx.isIncludeEmpty()) {
-      ctx.beginAssocMany(name);
-      for (Object bean : set) {
-        targetDescriptor.jsonWrite(ctx, (EntityBean) bean);
-      }
-      ctx.endAssocMany();
-    }
+    jsonWriteCollection(ctx, name, set);
   }
 }

src/main/java/io/ebeaninternal/server/deploy/BeanSetHelpElement.java

@@ -0,0 +1,30 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.api.json.SpiJsonWriter;
+
+/**
+ * Helper for element collection List.
+ */
+public class BeanSetHelpElement<T> extends BeanSetHelp<T> {
+
+  BeanSetHelpElement(BeanPropertyAssocMany<T> many) {
+    super(many);
+  }
+
+  @Override
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    Object elementValue = bean._ebean_getField(0);
+    if (withCheck) {
+      collection.internalAddWithCheck(elementValue);
+    } else {
+      collection.internalAdd(elementValue);
+    }
+  }
+
+  @Override
+  void jsonWriteElement(SpiJsonWriter ctx, Object element) {
+    many.jsonWriteElementValue(ctx, element);
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/BeanTable.java

@@ -30,7 +30,7 @@ public class BeanTable {
    */
   private final String baseTable;
 
-  private final BeanProperty[] idProperties;
+  private final BeanProperty idProperty;
 
   /**
    * Create the BeanTable.
@@ -39,7 +39,17 @@ public class BeanTable {
     this.owner = owner;
     this.beanType = mutable.getBeanType();
     this.baseTable = InternString.intern(mutable.getBaseTable());
-    this.idProperties = mutable.createIdProperties(owner);
+    this.idProperty = mutable.createIdProperty(owner);
+  }
+
+  /**
+   * Construct for element collection.
+   */
+  public BeanTable(BeanDescriptorMap owner, String tableName, Class<?> beanType) {
+    this.owner = owner;
+    this.beanType = beanType;
+    this.baseTable = tableName;
+    this.idProperty = null;
   }
 
   @Override
@@ -69,8 +79,8 @@ public class BeanTable {
   /**
    * Return the Id properties.
    */
-  public BeanProperty[] getIdProperties() {
-    return idProperties;
+  public BeanProperty getIdProperty() {
+    return idProperty;
   }
 
   /**
@@ -82,52 +92,51 @@ public class BeanTable {
 
   public void createJoinColumn(String foreignKeyPrefix, DeployTableJoin join, boolean reverse, String sqlFormulaSelect) {
 
-    boolean complexKey = false;
-    BeanProperty[] props = idProperties;
-
-    if (idProperties.length == 1) {
-      if (idProperties[0] instanceof BeanPropertyAssocOne<?>) {
-        BeanPropertyAssocOne<?> assocOne = (BeanPropertyAssocOne<?>) idProperties[0];
-        props = assocOne.getProperties();
-        complexKey = true;
-      }
+    if (idProperty == null) {
+      return;
     }
 
-    for (BeanProperty prop : props) {
+    if (idProperty instanceof BeanPropertyAssocOne<?>) {
+      BeanPropertyAssocOne<?> assocOne = (BeanPropertyAssocOne<?>) idProperty;
+      BeanProperty[] props = assocOne.getProperties();
+      for (BeanProperty prop : props) {
+        addToJoin(foreignKeyPrefix, join, reverse, sqlFormulaSelect, true, prop);
+      }
+    } else {
+      addToJoin(foreignKeyPrefix, join, reverse, sqlFormulaSelect, false, idProperty);
+    }
+  }
 
-      String lc = prop.getDbColumn();
-      String fk = lc;
-      if (foreignKeyPrefix != null) {
-        fk = owner.getNamingConvention().getForeignKey(foreignKeyPrefix, fk);
-      }
+  private void addToJoin(String foreignKeyPrefix, DeployTableJoin join, boolean reverse, String sqlFormulaSelect, boolean complexKey, BeanProperty prop) {
 
-      if (complexKey) {
-        // just to copy the column name rather than prefix with the foreignKeyPrefix.
-        // I think that with complex keys this is the more common approach.
-        logger.debug("On table[{}] foreign key column [{}]", baseTable, lc);
-        fk = lc;
-      }
-      if (sqlFormulaSelect != null) {
-        fk = sqlFormulaSelect;
-      }
-
-      DeployTableJoinColumn joinCol = new DeployTableJoinColumn(lc, fk);
-      joinCol.setForeignSqlFormula(sqlFormulaSelect);
-      if (reverse) {
-        joinCol = joinCol.reverse();
-      }
-      join.addJoinColumn(joinCol);
+    String lc = prop.getDbColumn();
+    String fk = lc;
+    if (foreignKeyPrefix != null) {
+      fk = owner.getNamingConvention().getForeignKey(foreignKeyPrefix, fk);
     }
 
+    if (complexKey) {
+      // just to copy the column name rather than prefix with the foreignKeyPrefix.
+      // I think that with complex keys this is the more common approach.
+      logger.debug("On table[{}] foreign key column [{}]", baseTable, lc);
+      fk = lc;
+    }
+    if (sqlFormulaSelect != null) {
+      fk = sqlFormulaSelect;
+    }
+
+    DeployTableJoinColumn joinCol = new DeployTableJoinColumn(lc, fk);
+    joinCol.setForeignSqlFormula(sqlFormulaSelect);
+    if (reverse) {
+      joinCol = joinCol.reverse();
+    }
+    join.addJoinColumn(joinCol);
   }
 
   /**
    * Return the primary key DB column.
    */
   public String getIdColumn() {
-    if (idProperties.length != 1) {
-      throw new IllegalStateException("Expecting only one Id column to join to on "+beanType);
-    }
-    return idProperties[0].dbColumn;
+    return idProperty.dbColumn;
   }
 }

src/main/java/io/ebeaninternal/server/deploy/DbReadContext.java

@@ -5,6 +5,7 @@ import io.ebean.bean.EntityBean;
 import io.ebean.bean.EntityBeanIntercept;
 import io.ebean.bean.PersistenceContext;
 import io.ebeaninternal.api.SpiQuery;
+import io.ebeaninternal.server.query.STreePropertyAssocMany;
 import io.ebeaninternal.server.type.DataReader;
 
 import java.util.Map;
@@ -68,7 +69,7 @@ public interface DbReadContext {
    * Return the property that is associated with the many. There can only be
    * one. This can be null.
    */
-  BeanPropertyAssocMany<?> getManyProperty();
+  STreePropertyAssocMany getManyProperty();
 
   /**
    * Set back the bean that has just been loaded with its id.

src/main/java/io/ebeaninternal/server/deploy/DynamicPropertyBase.java

@@ -1,7 +1,7 @@
 package io.ebeaninternal.server.deploy;
 
+import io.ebeaninternal.server.query.STreeProperty;
 import io.ebeaninternal.server.query.SqlJoinType;
-import io.ebeaninternal.server.query.SqlTreeProperty;
 import io.ebeaninternal.server.type.ScalarType;
 
 import java.util.List;
@@ -9,14 +9,14 @@ import java.util.List;
 /**
  * Abstract base for dynamic properties.
  */
-abstract class DynamicPropertyBase implements SqlTreeProperty {
+abstract class DynamicPropertyBase implements STreeProperty {
 
   final String name;
   final String fullName;
   final String elPrefix;
   final ScalarType<?> scalarType;
 
-  public DynamicPropertyBase(String name, String fullName, String elPrefix, ScalarType<?> scalarType) {
+  DynamicPropertyBase(String name, String fullName, String elPrefix, ScalarType<?> scalarType) {
     this.name = name;
     this.fullName = fullName;
     this.elPrefix = elPrefix;
@@ -43,6 +43,11 @@ abstract class DynamicPropertyBase implements SqlTreeProperty {
     return false;
   }
 
+  @Override
+  public boolean isFormula() {
+    return false;
+  }
+
   @Override
   public String getElPrefix() {
     return elPrefix;
@@ -67,4 +72,9 @@ abstract class DynamicPropertyBase implements SqlTreeProperty {
   public void appendFrom(DbSqlContext ctx, SqlJoinType joinType) {
     // do not add to from usually
   }
+
+  @Override
+  public String getEncryptKeyAsString() {
+    return null;
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/ElementCollector.java

@@ -0,0 +1,22 @@
+package io.ebeaninternal.server.deploy;
+
+/**
+ * Collects (List/Set/Map) of elements.
+ */
+public interface ElementCollector {
+
+  /**
+   * Add an element.
+   */
+  void addElement(Object element);
+
+  /**
+   * Add an element.
+   */
+  void addKeyValue(Object key, Object element);
+
+  /**
+   * Return the populated collection/map.
+   */
+  Object collection();
+}

src/main/java/io/ebeaninternal/server/deploy/ElementEntityBean.java

@@ -0,0 +1,81 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.EntityBean;
+import io.ebean.bean.EntityBeanIntercept;
+
+class ElementEntityBean implements EntityBean {
+
+  private final String[] properties;
+
+  private Object[] data;
+
+  private EntityBeanIntercept intercept;
+
+  ElementEntityBean(String[] properties) {
+    this.properties = properties;
+    this.intercept = new EntityBeanIntercept(this);
+  }
+
+  @Override
+  public String[] _ebean_getPropertyNames() {
+    return properties;
+  }
+
+  @Override
+  public String _ebean_getPropertyName(int pos) {
+    return properties[pos];
+  }
+
+  @Override
+  public String _ebean_getMarker() {
+    return null;
+  }
+
+  @Override
+  public Object _ebean_newInstance() {
+    return new ElementEntityBean(properties);
+  }
+
+  @Override
+  public void _ebean_setEmbeddedLoaded() {
+
+  }
+
+  @Override
+  public boolean _ebean_isEmbeddedNewOrDirty() {
+    return false;
+  }
+
+  @Override
+  public EntityBeanIntercept _ebean_getIntercept() {
+    return intercept;
+  }
+
+  @Override
+  public EntityBeanIntercept _ebean_intercept() {
+    return intercept;
+  }
+
+  @Override
+  public void _ebean_setField(int fieldIndex, Object value) {
+    if (data == null) {
+      data = new Object[properties.length];
+    }
+    data[fieldIndex] = value;
+  }
+
+  @Override
+  public void _ebean_setFieldIntercept(int fieldIndex, Object value) {
+    _ebean_setField(fieldIndex, value);
+  }
+
+  @Override
+  public Object _ebean_getField(int fieldIndex) {
+    return data == null ? null : data[fieldIndex];
+  }
+
+  @Override
+  public Object _ebean_getFieldIntercept(int fieldIndex) {
+    return _ebean_getField(fieldIndex);
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/ElementHelp.java

@@ -0,0 +1,13 @@
+package io.ebeaninternal.server.deploy;
+
+/**
+ * Helper for handling ElementCollection.
+ */
+interface ElementHelp {
+
+  /**
+   * Return a new collector.
+   */
+  ElementCollector createCollector();
+
+}

src/main/java/io/ebeaninternal/server/deploy/ElementHelpList.java

@@ -0,0 +1,37 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.common.BeanList;
+
+import java.util.ArrayList;
+import java.util.List;
+
+class ElementHelpList implements ElementHelp {
+
+  @Override
+  public ElementCollector createCollector() {
+    return new Collector();
+  }
+
+  private static class Collector implements ElementCollector {
+
+    private List<Object> list = new ArrayList<>();
+
+    @Override
+    public void addElement(Object element) {
+      list.add(element);
+    }
+
+    @Override
+    public void addKeyValue(Object key, Object element) {
+      throw new IllegalStateException("never called");
+    }
+
+    @Override
+    public Object collection() {
+      BeanList<Object> beanList = new BeanList<>(list);
+      beanList.setModifyListening(BeanCollection.ModifyListenMode.ALL);
+      return beanList;
+    }
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/ElementHelpMap.java

@@ -0,0 +1,37 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.common.BeanMap;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+class ElementHelpMap implements ElementHelp {
+
+  @Override
+  public ElementCollector createCollector() {
+    return new Collector();
+  }
+
+  private static class Collector implements ElementCollector {
+
+    private Map<Object, Object> map = new LinkedHashMap<>();
+
+    @Override
+    public void addElement(Object element) {
+      throw new IllegalStateException("never called");
+    }
+
+    @Override
+    public void addKeyValue(Object key, Object element) {
+      map.put(key, element);
+    }
+
+    @Override
+    public Object collection() {
+      BeanMap<Object, Object> beanMap = new BeanMap<>(map);
+      beanMap.setModifyListening(BeanCollection.ModifyListenMode.ALL);
+      return beanMap;
+    }
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/ElementHelpSet.java

@@ -0,0 +1,37 @@
+package io.ebeaninternal.server.deploy;
+
+import io.ebean.bean.BeanCollection;
+import io.ebean.common.BeanSet;
+
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+class ElementHelpSet implements ElementHelp {
+
+  @Override
+  public ElementCollector createCollector() {
+    return new Collector();
+  }
+
+  private static class Collector implements ElementCollector {
+
+    private Set<Object> set = new LinkedHashSet<>();
+
+    @Override
+    public void addElement(Object element) {
+      set.add(element);
+    }
+
+    @Override
+    public void addKeyValue(Object key, Object element) {
+      throw new IllegalStateException("never called");
+    }
+
+    @Override
+    public Object collection() {
+      BeanSet<Object> beanSet = new BeanSet<>(set);
+      beanSet.setModifyListening(BeanCollection.ModifyListenMode.ALL);
+      return beanSet;
+    }
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/FormulaPropertyPath.java

@@ -1,7 +1,7 @@
 package io.ebeaninternal.server.deploy;
 
 import io.ebeaninternal.server.el.ElPropertyDeploy;
-import io.ebeaninternal.server.query.SqlTreeProperty;
+import io.ebeaninternal.server.query.STreeProperty;
 import io.ebeaninternal.server.type.ScalarType;
 
 import java.sql.Types;
@@ -89,7 +89,7 @@ class FormulaPropertyPath {
     return alias;
   }
 
-  SqlTreeProperty build() {
+  STreeProperty build() {
 
     DeployPropertyParser parser = descriptor.parser().setCatchFirst(true);
 

src/main/java/io/ebeaninternal/server/deploy/InheritInfo.java

@@ -6,6 +6,7 @@ import io.ebeaninternal.server.deploy.id.IdBinder;
 import io.ebeaninternal.server.deploy.parse.DeployInheritInfo;
 import io.ebeaninternal.server.query.SqlTreeProperties;
 
+import java.lang.reflect.Modifier;
 import javax.persistence.PersistenceException;
 import java.sql.SQLException;
 import java.util.ArrayList;
@@ -184,7 +185,7 @@ public class InheritInfo {
 
     for (InheritInfo childInfo : children) {
       // recursively search this child bean descriptor
-      prop = childInfo.desc().findBeanProperty(propertyName);
+      prop = childInfo.desc().findProperty(propertyName);
       if (prop != null) {
         return prop;
       }
@@ -291,7 +292,7 @@ public class InheritInfo {
    * Return true if this is considered a concrete type in the inheritance hierarchy.
    */
   public boolean isConcrete() {
-    return discriminatorValue != null;
+    return !Modifier.isAbstract(type.getModifiers());
   }
 
   /**

src/main/java/io/ebeaninternal/server/deploy/id/IdBinder.java

@@ -6,6 +6,7 @@ import io.ebeaninternal.server.core.DefaultSqlUpdate;
 import io.ebeaninternal.server.deploy.BeanProperty;
 import io.ebeaninternal.server.deploy.DbReadContext;
 import io.ebeaninternal.server.deploy.DbSqlContext;
+import io.ebeaninternal.server.query.STreeProperty;
 import io.ebeaninternal.server.type.DataBind;
 
 import java.io.DataInput;
@@ -52,7 +53,7 @@ public interface IdBinder {
   /**
    * Return the Id BeanProperty.
    */
-  BeanProperty getBeanProperty();
+  STreeProperty getBeanProperty();
 
   /**
    * Find a BeanProperty that is mapped to the database column.

src/main/java/io/ebeaninternal/server/deploy/id/IdBinderEmbedded.java

@@ -277,7 +277,7 @@ public final class IdBinderEmbedded implements IdBinder {
   public void bindId(DefaultSqlUpdate sqlUpdate, Object value) {
     for (BeanProperty prop : props) {
       Object embFieldValue = prop.getValue((EntityBean) value);
-      sqlUpdate.addParameter(embFieldValue);
+      sqlUpdate.setNextParameter(embFieldValue);
     }
   }
 

src/main/java/io/ebeaninternal/server/deploy/id/IdBinderSimple.java

@@ -146,7 +146,7 @@ public final class IdBinderSimple implements IdBinder {
 
   @Override
   public void addIdInBindValues(DefaultSqlUpdate sqlUpdate, Collection<?> ids) {
-    sqlUpdate.addParameter(new MultiValueWrapper(ids));
+    sqlUpdate.setNextParameter(new MultiValueWrapper(ids));
   }
 
   @Override
@@ -171,7 +171,7 @@ public final class IdBinderSimple implements IdBinder {
 
   @Override
   public void bindId(DefaultSqlUpdate sqlUpdate, Object value) {
-    sqlUpdate.addParameter(value);
+    sqlUpdate.setNextParameter(value);
   }
 
   @Override

src/main/java/io/ebeaninternal/server/deploy/meta/BeanPropertyElementSetter.java

@@ -0,0 +1,26 @@
+package io.ebeaninternal.server.deploy.meta;
+
+import io.ebean.bean.EntityBean;
+import io.ebeaninternal.server.properties.BeanPropertySetter;
+
+/**
+ * Setter used for "element beans" with ElementCollection.
+ */
+class BeanPropertyElementSetter implements BeanPropertySetter {
+
+  private final int pos;
+
+  BeanPropertyElementSetter(int pos) {
+    this.pos = pos;
+  }
+
+  @Override
+  public void set(EntityBean bean, Object value) {
+    bean._ebean_setField(pos, value);
+  }
+
+  @Override
+  public void setIntercept(EntityBean bean, Object value) {
+    set(bean, value);
+  }
+}

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanDescriptor.java

@@ -15,7 +15,6 @@ import io.ebean.event.BeanPostLoad;
 import io.ebean.event.BeanQueryAdapter;
 import io.ebean.event.changelog.ChangeLogFilter;
 import io.ebean.text.PathProperties;
-import io.ebean.util.CamelCaseHelper;
 import io.ebeaninternal.api.ConcurrencyMode;
 import io.ebeaninternal.server.core.CacheOptions;
 import io.ebeaninternal.server.deploy.BeanDescriptor.EntityType;
@@ -91,6 +90,10 @@ public class DeployBeanDescriptor<T> {
    */
   private IdType idType;
 
+  private Class<?> idClass;
+
+  private DeployBeanPropertyAssocOne<?> idClassProperty;
+
   /**
    * Set to true if the identity is default for the platform.
    */
@@ -205,7 +208,7 @@ public class DeployBeanDescriptor<T> {
   private DocStoreMode docStoreUpdate;
   private DocStoreMode docStoreDelete;
 
-  private List<DeployBeanProperty> idProperties;
+  private DeployBeanProperty idProperty;
   private TableJoin primaryKeyJoin;
 
   private short profileId;
@@ -219,6 +222,20 @@ public class DeployBeanDescriptor<T> {
     this.beanType = beanType;
   }
 
+  /**
+   * Set the IdClass to use.
+   */
+  public void setIdClass(Class idClass) {
+    this.idClass = idClass;
+  }
+
+  /**
+   * Return true if there is a IdClass set.
+   */
+  public boolean isIdClass() {
+    return idClass != null;
+  }
+
   /**
    * PK is also a FK.
    */
@@ -335,7 +352,7 @@ public class DeployBeanDescriptor<T> {
 
     DeployBeanTable beanTable = new DeployBeanTable(getBeanType());
     beanTable.setBaseTable(baseTable);
-    beanTable.setIdProperties(propertiesId());
+    beanTable.setIdProperty(idProperty());
 
     return beanTable;
   }
@@ -443,6 +460,10 @@ public class DeployBeanDescriptor<T> {
     return cacheOptions;
   }
 
+  public DeployBeanPropertyAssocOne<?> getIdClassProperty() {
+    return idClassProperty;
+  }
+
   public DeployBeanPropertyAssocOne<?> getUnidirectional() {
     return unidirectional;
   }
@@ -684,6 +705,15 @@ public class DeployBeanDescriptor<T> {
     }
   }
 
+  public void postAnnotations() {
+    if (idClass != null) {
+      idClassProperty = new DeployBeanPropertyAssocOne<>(this, idClass);
+      idClassProperty.setName("_idClass");
+      idClassProperty.setEmbedded();
+      idClassProperty.setNullable(false);
+    }
+  }
+
   /**
    * Add a bean property.
    */
@@ -691,32 +721,8 @@ public class DeployBeanDescriptor<T> {
     return propMap.put(prop.getName(), prop);
   }
 
-  /**
-   * Find the matching property for a given property name or dbColumn.
-   * <p>
-   * This is primarily to find imported primary key columns (ManyToOne that also match the PK).
-   * </p>
-   */
-  DeployBeanProperty findMatch(String propertyName, String dbColumn) {
-
-    DeployBeanProperty prop = propMap.get(propertyName);
-    if (prop != null) {
-      return prop;
-    }
-    if (dbColumn != null) {
-      String asCamel = CamelCaseHelper.toCamelFromUnderscore(dbColumn);
-      prop = propMap.get(asCamel);
-      if (prop != null) {
-        return prop;
-      }
-      // scan looking for dbColumn match
-      for (DeployBeanProperty property : propMap.values()) {
-        if (dbColumn.equals(property.getDbColumn())) {
-          return property;
-        }
-      }
-    }
-    return null;
+  public Collection<DeployBeanProperty> properties() {
+    return propMap.values();
   }
 
   /**
@@ -935,16 +941,14 @@ public class DeployBeanDescriptor<T> {
    */
   public boolean isPrimaryKeyCompoundOrNonNumeric() {
 
-    List<DeployBeanProperty> ids = propertiesId();
-    if (ids.size() != 1) {
-      // compound key
-      return true;
+    DeployBeanProperty id = idProperty();
+    if (id == null) {
+      return false;
     }
-    DeployBeanProperty p = ids.get(0);
-    if (p instanceof DeployBeanPropertyAssocOne<?>) {
-      return ((DeployBeanPropertyAssocOne<?>) p).isCompound();
+    if (id instanceof DeployBeanPropertyAssocOne<?>) {
+      return ((DeployBeanPropertyAssocOne<?>) id).isCompound();
     } else {
-      return !p.isDbNumberType();
+      return !id.isDbNumberType();
     }
   }
 
@@ -953,37 +957,32 @@ public class DeployBeanDescriptor<T> {
    * compound). This is for the purpose of defining a sequence name.
    */
   public String getSinglePrimaryKeyColumn() {
-    List<DeployBeanProperty> ids = propertiesId();
-    if (ids.size() == 1) {
-      DeployBeanProperty p = ids.get(0);
-      if (p instanceof DeployBeanPropertyAssoc<?>) {
+    DeployBeanProperty id = idProperty();
+    if (id != null) {
+      if (id instanceof DeployBeanPropertyAssoc<?>) {
         // its a compound primary key
         return null;
       } else {
-        return p.getDbColumn();
+        return id.getDbColumn();
       }
     }
     return null;
   }
 
   /**
-   * Return the BeanProperty that make up the unique id.
-   * <p>
-   * The order of these properties can be relied on to be consistent if the bean
-   * itself doesn't change or the xml deployment order does not change.
-   * </p>
+   * Return the BeanProperty that is the Id.
    */
-  public List<DeployBeanProperty> propertiesId() {
-
-    if (idProperties == null) {
-      idProperties = new ArrayList<>(2);
-      for (DeployBeanProperty prop : propMap.values()) {
-        if (prop.isId()) {
-          idProperties.add(prop);
-        }
+  public DeployBeanProperty idProperty() {
+    if (idProperty != null) {
+      return idProperty;
+    }
+    for (DeployBeanProperty prop : propMap.values()) {
+      if (prop.isId()) {
+        idProperty = prop;
+        return idProperty;
       }
     }
-    return idProperties;
+    return null;
   }
 
   public DeployBeanPropertyAssocOne<?> findJoinToTable(String tableName) {

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanProperty.java

@@ -51,6 +51,7 @@ public class DeployBeanProperty {
   private static final int AUDITCOLUMN_ORDER = -1000000;
   private static final int VERSIONCOLUMN_ORDER = -1000000;
   private static final Set<Class<?>> PRIMITIVE_NUMBER_TYPES = new HashSet<>();
+
   static {
     PRIMITIVE_NUMBER_TYPES.add(float.class);
     PRIMITIVE_NUMBER_TYPES.add(double.class);
@@ -64,6 +65,8 @@ public class DeployBeanProperty {
    */
   private boolean id;
 
+  boolean importedPrimaryKey;
+
   /**
    * Flag to mark the property as embedded. This could be on
    * BeanPropertyAssocOne rather than here. Put it here for checking Id type
@@ -207,6 +210,8 @@ public class DeployBeanProperty {
 
   private boolean undirectionalShadow;
 
+  private boolean elementProperty;
+
   private int sortOrder;
 
   private boolean excludedFromHistory;
@@ -441,7 +446,11 @@ public class DeployBeanProperty {
   }
 
   public BeanPropertySetter getSetter() {
-    return setter;
+    if (elementProperty) {
+      return new BeanPropertyElementSetter(sortOrder);
+    } else {
+      return setter;
+    }
   }
 
   /**
@@ -611,6 +620,16 @@ public class DeployBeanProperty {
     this.dbUpdateable = false;
   }
 
+  public void setImportedPrimaryKey() {
+    this.importedPrimaryKey = true;
+  }
+
+  /**
+   * Set to true if this is part of the primary key.
+   */
+  public void setImportedPrimaryKeyColumn(DeployBeanProperty primaryKey) {
+    this.importedPrimaryKey = true;
+  }
 
   public boolean isAggregation() {
     return aggregation != null;
@@ -889,6 +908,13 @@ public class DeployBeanProperty {
     return genericType;
   }
 
+  /**
+   * Return true if this is part of the primary key.
+   */
+  public boolean isImportedPrimaryKey() {
+    return importedPrimaryKey;
+  }
+
   /**
    * Return true if this is included in the unique id.
    */
@@ -1046,6 +1072,10 @@ public class DeployBeanProperty {
     return tenantId;
   }
 
+  public boolean isIdClass() {
+    return desc.isIdClass();
+  }
+
   public void addDbMigrationInfo(DbMigrationInfo info) {
     if (dbMigrationInfos == null) {
       dbMigrationInfos = new ArrayList<>();
@@ -1057,4 +1087,10 @@ public class DeployBeanProperty {
     return dbMigrationInfos;
   }
 
+  /**
+   * Set when this property is part of a 'element bean' used with ElementCollection.
+   */
+  public void setElementProperty() {
+    this.elementProperty = true;
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanPropertyAssocMany.java

@@ -1,8 +1,12 @@
 package io.ebeaninternal.server.deploy.meta;
 
 import io.ebean.bean.BeanCollection.ModifyListenMode;
+import io.ebeaninternal.server.deploy.BeanDescriptor;
 import io.ebeaninternal.server.deploy.ManyType;
 import io.ebeaninternal.server.deploy.TableJoin;
+import io.ebeaninternal.server.type.TypeReflectHelper;
+
+import java.lang.reflect.Type;
 
 /**
  * Property mapped to a List Set or Map.
@@ -23,6 +27,8 @@ public class DeployBeanPropertyAssocMany<T> extends DeployBeanPropertyAssoc<T> {
 
   private boolean o2mJoinTable;
 
+  private boolean elementCollection;
+
   /**
    * Flag to indicate this is a unidirectional relationship.
    */
@@ -46,6 +52,11 @@ public class DeployBeanPropertyAssocMany<T> extends DeployBeanPropertyAssoc<T> {
 
   private DeployOrderColumn orderColumn;
 
+  /**
+   * Effectively the dynamically created target descriptor (that doesn't have a mapped type/class per say).
+   */
+  private BeanDescriptor<?> elementDescriptor;
+
   /**
    * Create this property.
    */
@@ -171,6 +182,14 @@ public class DeployBeanPropertyAssocMany<T> extends DeployBeanPropertyAssoc<T> {
     return fetchOrderBy;
   }
 
+  /**
+   * Return the type of the map key (valid only when this property is a Map).
+   */
+  public Class<?> getMapKeyType() {
+    Type genericType = getField().getGenericType();
+    return TypeReflectHelper.getMapKeyType(genericType);
+  }
+
   /**
    * Return the default mapKey when returning a Map.
    */
@@ -231,5 +250,24 @@ public class DeployBeanPropertyAssocMany<T> extends DeployBeanPropertyAssoc<T> {
     this.o2mJoinTable = true;
     setModifyListenMode(ModifyListenMode.ALL);
   }
+
+  public void setElementCollection() {
+    elementCollection = true;
+    cascadeInfo.setSaveDelete(true, true);
+    setModifyListenMode(ModifyListenMode.ALL);
+  }
+
+  public boolean isElementCollection() {
+    return elementCollection;
+  }
+
+  public void setElementDescriptor(BeanDescriptor<?> elementDescriptor) {
+    this.elementDescriptor = elementDescriptor;
+  }
+
+  @SuppressWarnings("unchecked")
+  public <A> BeanDescriptor<A> getElementDescriptor() {
+    return (BeanDescriptor<A>)elementDescriptor;
+  }
 }
 

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanPropertyAssocOne.java

@@ -1,6 +1,7 @@
 package io.ebeaninternal.server.deploy.meta;
 
 import io.ebeaninternal.server.deploy.PropertyForeignKey;
+import io.ebeaninternal.server.query.SqlJoinType;
 
 import javax.persistence.CascadeType;
 
@@ -17,8 +18,6 @@ public class DeployBeanPropertyAssocOne<T> extends DeployBeanPropertyAssoc<T> {
 
   private boolean primaryKeyExport;
 
-  private boolean importedPrimaryKey;
-
   private DeployBeanEmbedded deployEmbedded;
 
   private String columnPrefix;
@@ -92,17 +91,11 @@ public class DeployBeanPropertyAssocOne<T> extends DeployBeanPropertyAssoc<T> {
     this.oneToOneExported = true;
   }
 
-  /**
-   * Return true if this is part of the primary key.
-   */
-  public boolean isImportedPrimaryKey() {
-    return importedPrimaryKey;
-  }
-
   /**
    * Set to true if this is part of the primary key.
    */
-  void setImportedPrimaryKey(DeployBeanProperty primaryKey) {
+  @Override
+  public void setImportedPrimaryKeyColumn(DeployBeanProperty primaryKey) {
     this.importedPrimaryKey = true;
     String dbColumn = primaryKey.getDbColumn();
     if (dbColumn != null) {
@@ -170,4 +163,12 @@ public class DeployBeanPropertyAssocOne<T> extends DeployBeanPropertyAssoc<T> {
   public boolean isOrphanRemoval() {
     return orphanRemoval;
   }
+
+  public void setJoinType(boolean outerJoin) {
+    tableJoin.setType(outerJoin ? SqlJoinType.OUTER : SqlJoinType.INNER);
+  }
+
+  public void setJoinColumns(DeployTableJoinColumn[] columns, boolean reverse) {
+    tableJoin.setColumns(columns, reverse);
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanPropertyLists.java

@@ -5,6 +5,7 @@ import io.ebeaninternal.server.deploy.BeanDescriptorMap;
 import io.ebeaninternal.server.deploy.BeanProperty;
 import io.ebeaninternal.server.deploy.BeanPropertyAssocMany;
 import io.ebeaninternal.server.deploy.BeanPropertyAssocOne;
+import io.ebeaninternal.server.deploy.BeanPropertyIdClass;
 import io.ebeaninternal.server.deploy.BeanPropertyOrderColumn;
 import io.ebeaninternal.server.deploy.BeanPropertySimpleCollection;
 import io.ebeaninternal.server.deploy.InheritInfo;
@@ -39,7 +40,7 @@ public class DeployBeanPropertyLists {
 
   private final LinkedHashMap<String, BeanProperty> propertyMap;
 
-  private final List<BeanProperty> ids = new ArrayList<>();
+  private BeanProperty id;
 
   private final List<BeanProperty> local = new ArrayList<>();
 
@@ -70,7 +71,13 @@ public class DeployBeanPropertyLists {
   public DeployBeanPropertyLists(BeanDescriptorMap owner, BeanDescriptor<?> desc, DeployBeanDescriptor<?> deploy) {
     this.desc = desc;
 
-    setImportedPrimaryKeys(deploy);
+    DeployBeanPropertyAssocOne<?> deployId = deploy.getIdClassProperty();
+    if (deployId != null) {
+      this.id = new BeanPropertyIdClass(owner, desc, deployId);
+      setImportedPrimaryKeysFor(deploy, deployId);
+    } else {
+      setImportedPrimaryKeys(deploy);
+    }
 
     DeployBeanProperty deployOrderColumn = deploy.getOrderColumn();
     this.orderColumn = deployOrderColumn != null ? new BeanPropertyOrderColumn(desc, deployOrderColumn) : null;
@@ -142,23 +149,43 @@ public class DeployBeanPropertyLists {
    * </p>
    */
   private void setImportedPrimaryKeys(DeployBeanDescriptor<?> deploy) {
+    DeployBeanProperty id = deploy.idProperty();
+    if (id instanceof DeployBeanPropertyAssocOne<?>) {
+      setImportedPrimaryKeysFor(deploy, (DeployBeanPropertyAssocOne<?>) id);
+    }
+  }
 
-    List<DeployBeanProperty> ids = deploy.propertiesId();
-    if (ids.size() == 1) {
-      DeployBeanProperty id = ids.get(0);
-      if (id instanceof DeployBeanPropertyAssocOne<?>) {
-        // only interested if the primary key is a compound key
-        DeployBeanDescriptor<?> targetDeploy = ((DeployBeanPropertyAssocOne<?>) id).getTargetDeploy();
-        for (DeployBeanPropertyAssocOne<?> assoc : deploy.propertiesAssocOne()) {
-          DeployBeanProperty pkMatch = targetDeploy.findMatch(assoc.getName(), assoc.getDbColumn());
-          if (pkMatch != null) {
-            assoc.setImportedPrimaryKey(pkMatch);
-          }
-        }
+  private void setImportedPrimaryKeysFor(DeployBeanDescriptor<?> deploy, DeployBeanPropertyAssocOne<?> id) {
+
+    for (DeployBeanProperty prop : id.getTargetDeploy().properties()) {
+      DeployBeanProperty match = findImported(deploy, prop);
+      if (match != null) {
+        match.setImportedPrimaryKeyColumn(prop);
       }
     }
   }
 
+  private DeployBeanProperty findImported(DeployBeanDescriptor<?> deploy, DeployBeanProperty embeddedScalar) {
+
+    // the logical name and db column we are looking for a match on
+    String name = embeddedScalar.getName();
+    String dbColumn = embeddedScalar.getDbColumn();
+
+    DeployBeanProperty match = deploy.getBeanProperty(name);
+    if (match != null) {
+      return match;
+    }
+    // could look to match more by dbColumn
+
+    for (DeployBeanPropertyAssocOne<?> assocOne : deploy.propertiesAssocOne()) {
+      if (name.equals(assocOne.getName()) || (dbColumn != null && dbColumn.equals(assocOne.getDbColumn()))) {
+        return assocOne;
+      }
+    }
+
+    return null;
+  }
+
   /**
    * Return the unidirectional.
    */
@@ -188,12 +215,13 @@ public class DeployBeanPropertyLists {
       return;
     }
     if (prop.isId()) {
-      ids.add(prop);
+      if (id != null) {
+        throw new IllegalStateException("More that one @Id property on " + desc.getFullName() + " ?");
+      }
+      id = prop;
       return;
-    } else {
-      nonTransients.add(prop);
     }
-
+    nonTransients.add(prop);
     if (prop.isMutableScalarType()) {
       mutable.add(prop);
     }
@@ -255,15 +283,7 @@ public class DeployBeanPropertyLists {
   }
 
   public BeanProperty getId() {
-    if (ids.size() > 1) {
-      String msg = "Issue with bean " + desc + ". Ebean does not support multiple @Id properties. You need to convert to using an @EmbeddedId."
-        + " Please email the ebean google group if you need further clarification.";
-      throw new IllegalStateException(msg);
-    }
-    if (ids.isEmpty()) {
-      return null;
-    }
-    return ids.get(0);
+    return id;
   }
 
   public BeanProperty[] getNonTransients() {

src/main/java/io/ebeaninternal/server/deploy/meta/DeployBeanTable.java

@@ -4,9 +4,6 @@ import io.ebeaninternal.server.deploy.BeanDescriptorMap;
 import io.ebeaninternal.server.deploy.BeanProperty;
 import io.ebeaninternal.server.deploy.BeanPropertyAssocOne;
 
-import java.util.List;
-
-
 /**
  * Used for associated beans in place of a BeanDescriptor. This is done to avoid
  * recursion issues due to the potentially bi-directional and circular
@@ -25,12 +22,12 @@ public class DeployBeanTable {
    */
   private String baseTable;
 
-  private List<DeployBeanProperty> idProperties;
+  private DeployBeanProperty idProperty;
 
   /**
    * Create the BeanTable.
    */
-  public DeployBeanTable(Class<?> beanType) {
+  DeployBeanTable(Class<?> beanType) {
     this.beanType = beanType;
   }
 
@@ -53,12 +50,8 @@ public class DeployBeanTable {
   /**
    * Return the id properties.
    */
-  public BeanProperty[] createIdProperties(BeanDescriptorMap owner) {
-    BeanProperty[] props = new BeanProperty[idProperties.size()];
-    for (int i = 0; i < idProperties.size(); i++) {
-      props[i] = createProperty(owner, idProperties.get(i));
-    }
-    return props;
+  public BeanProperty createIdProperty(BeanDescriptorMap owner) {
+    return idProperty == null ? null : createProperty(owner, idProperty);
   }
 
   @SuppressWarnings({"unchecked", "rawtypes"})
@@ -70,14 +63,13 @@ public class DeployBeanTable {
     } else {
       return new BeanProperty(prop);
     }
-
   }
 
   /**
    * Set the Id properties.
    */
-  public void setIdProperties(List<DeployBeanProperty> idProperties) {
-    this.idProperties = idProperties;
+  public void setIdProperty(DeployBeanProperty idProperty) {
+    this.idProperty = idProperty;
   }
 
   /**

src/main/java/io/ebeaninternal/server/deploy/meta/DeployTableJoinColumn.java

@@ -92,9 +92,9 @@ public class DeployTableJoinColumn {
 
   private void setReferencedColumn(BeanTable beanTable) {
     if (localDbColumn == null) {
-      BeanProperty[] idProperties = beanTable.getIdProperties();
-      if (idProperties.length == 1) {
-        localDbColumn = idProperties[0].getDbColumn();
+      BeanProperty idProperty = beanTable.getIdProperty();
+      if (idProperty != null) {
+        localDbColumn = idProperty.getDbColumn();
       }
     }
   }

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationAssocManys.java

@@ -7,22 +7,30 @@ import io.ebean.annotation.Where;
 import io.ebean.bean.BeanCollection.ModifyListenMode;
 import io.ebean.config.NamingConvention;
 import io.ebean.config.TableName;
+import io.ebean.util.CamelCaseHelper;
 import io.ebean.util.StringHelper;
 import io.ebeaninternal.server.deploy.BeanDescriptorManager;
 import io.ebeaninternal.server.deploy.BeanProperty;
 import io.ebeaninternal.server.deploy.BeanTable;
+import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
 import io.ebeaninternal.server.deploy.meta.DeployBeanProperty;
 import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocMany;
+import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
 import io.ebeaninternal.server.deploy.meta.DeployOrderColumn;
 import io.ebeaninternal.server.deploy.meta.DeployTableJoin;
 import io.ebeaninternal.server.deploy.meta.DeployTableJoinColumn;
 import io.ebeaninternal.server.query.SqlJoinType;
+import io.ebeaninternal.server.type.ScalarType;
 
 import javax.persistence.CascadeType;
+import javax.persistence.CollectionTable;
+import javax.persistence.Column;
+import javax.persistence.ElementCollection;
 import javax.persistence.JoinColumn;
 import javax.persistence.JoinTable;
 import javax.persistence.ManyToMany;
 import javax.persistence.MapKey;
+import javax.persistence.MapKeyColumn;
 import javax.persistence.OneToMany;
 import javax.persistence.OrderBy;
 import javax.persistence.OrderColumn;
@@ -38,8 +46,8 @@ class AnnotationAssocManys extends AnnotationParser {
   /**
    * Create with the DeployInfo.
    */
-  AnnotationAssocManys(DeployBeanInfo<?> info, boolean javaxValidationAnnotations, BeanDescriptorManager factory) {
-    super(info, javaxValidationAnnotations);
+  AnnotationAssocManys(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig, BeanDescriptorManager factory) {
+    super(info, readConfig);
     this.factory = factory;
   }
 
@@ -82,6 +90,10 @@ class AnnotationAssocManys extends AnnotationParser {
     if (manyToMany != null) {
       readToMany(manyToMany, prop);
     }
+    ElementCollection elementCollection = get(prop, ElementCollection.class);
+    if (elementCollection != null) {
+      readElementCollection(prop, elementCollection);
+    }
 
     if (get(prop, HistoryExclude.class) != null) {
       prop.setExcludedFromHistory();
@@ -160,6 +172,111 @@ class AnnotationAssocManys extends AnnotationParser {
     }
   }
 
+  private void readElementCollection(DeployBeanPropertyAssocMany<?> prop, ElementCollection elementCollection) {
+
+    prop.setElementCollection();
+    if (!elementCollection.targetClass().equals(void.class)) {
+      prop.setTargetType(elementCollection.targetClass());
+    }
+    Column column = get(prop, Column.class);
+    if (column != null) {
+      prop.setDbColumn(column.name());
+      prop.setDbLength(column.length());
+      prop.setDbScale(column.scale());
+    }
+
+    CollectionTable collectionTable = get(prop, CollectionTable.class);
+
+    String fullTableName = getFullTableName(collectionTable);
+    if (fullTableName == null) {
+      fullTableName = descriptor.getBaseTable()+"_"+ CamelCaseHelper.toUnderscoreFromCamel(prop.getName());
+    }
+
+    BeanTable localTable = factory.getBeanTable(descriptor.getBeanType());
+    if (collectionTable != null) {
+      prop.getTableJoin().addJoinColumn(true, collectionTable.joinColumns(), localTable);
+    }
+    if (!prop.getTableJoin().hasJoinColumns()) {
+      BeanProperty localId = localTable.getIdProperty();
+      if (localId != null) {
+        // add foreign key based on convention
+        String fkColName = namingConvention.getForeignKey(descriptor.getBaseTable(), localId.getName());
+        prop.getTableJoin().addJoinColumn(new DeployTableJoinColumn(localId.getDbColumn(), fkColName));
+      }
+    }
+
+    BeanTable beanTable = factory.createCollectionBeanTable(fullTableName, prop.getTargetType());
+    prop.setBeanTable(beanTable);
+
+    Class<?> elementType = prop.getTargetType();
+
+    DeployBeanDescriptor<?> elementDescriptor = factory.createDeployDescriptor(elementType);
+    elementDescriptor.setBaseTable(new TableName(fullTableName), readConfig.getAsOfViewSuffix(), readConfig.getVersionsBetweenSuffix());
+
+    int sortOrder = 0;
+    if (!prop.getManyType().isMap()) {
+      elementDescriptor.setProperties(new String[]{"value"});
+    } else {
+      elementDescriptor.setProperties(new String[]{"key", "value"});
+      String dbKeyColumn = "mkey";
+      MapKeyColumn mapKeyColumn = get(prop, MapKeyColumn.class);
+      if (mapKeyColumn != null) {
+        dbKeyColumn = mapKeyColumn.name();
+      }
+
+      ScalarType<?> keyScalarType = util.getTypeManager().getScalarType(prop.getMapKeyType());
+
+      DeployBeanProperty keyProp = new DeployBeanProperty(elementDescriptor, elementType, keyScalarType, null);
+      setElementProperty(keyProp, "key", dbKeyColumn, sortOrder++);
+      elementDescriptor.addBeanProperty(keyProp);
+      if (mapKeyColumn != null) {
+        keyProp.setDbLength(mapKeyColumn.length());
+        keyProp.setDbScale(mapKeyColumn.scale());
+        keyProp.setUnique(mapKeyColumn.unique());
+      }
+    }
+
+    ScalarType<?> valueScalarType = util.getTypeManager().getScalarType(elementType);
+
+    boolean scalar = true;
+    if (valueScalarType == null) {
+      // embedded value type
+      scalar = false;
+      DeployBeanPropertyAssocOne valueProp = new DeployBeanPropertyAssocOne<>(elementDescriptor, elementType);
+      valueProp.setName("value");
+      valueProp.setEmbedded();
+      valueProp.setElementProperty();
+      valueProp.setSortOrder(sortOrder++);
+      elementDescriptor.addBeanProperty(valueProp);
+
+    } else {
+      // scalar value type
+      DeployBeanProperty valueProp = new DeployBeanProperty(elementDescriptor, elementType, valueScalarType, null);
+      setElementProperty(valueProp, "value", prop.getDbColumn(), sortOrder++);
+      if (column != null) {
+        valueProp.setDbLength(column.length());
+        valueProp.setDbScale(column.scale());
+      }
+      elementDescriptor.addBeanProperty(valueProp);
+    }
+
+    elementDescriptor.setName(prop.getFullBeanName());
+
+    factory.createUnidirectional(elementDescriptor, prop.getOwningType(), beanTable, prop.getTableJoin());
+    prop.setElementDescriptor(factory.createElementDescriptor(elementDescriptor, prop.getManyType(), scalar));
+  }
+
+  private void setElementProperty(DeployBeanProperty elementProp, String name, String dbColumn, int sortOrder) {
+    elementProp.setName(name);
+    elementProp.setDbColumn(dbColumn);
+    elementProp.setNullable(false);
+    elementProp.setDbInsertable(true);
+    elementProp.setDbUpdateable(true);
+    elementProp.setDbRead(true);
+    elementProp.setSortOrder(sortOrder);
+    elementProp.setElementProperty();
+  }
+
   /**
    * Define the joins for a ManyToMany relationship.
    * <p>
@@ -204,6 +321,24 @@ class AnnotationAssocManys extends AnnotationParser {
     return sb.toString();
   }
 
+  /**
+   * Return the full table name
+   */
+  private String getFullTableName(CollectionTable collectionTable) {
+    if (collectionTable == null || collectionTable.name().isEmpty()) {
+      return null;
+    }
+    StringBuilder sb = new StringBuilder();
+    if (!StringHelper.isNull(collectionTable.catalog())) {
+      sb.append(collectionTable.catalog()).append(".");
+    }
+    if (!StringHelper.isNull(collectionTable.schema())) {
+      sb.append(collectionTable.schema()).append(".");
+    }
+    sb.append(collectionTable.name());
+    return sb.toString();
+  }
+
   /**
    * Define intersection table and foreign key columns for ManyToMany.
    * <p>
@@ -247,8 +382,8 @@ class AnnotationAssocManys extends AnnotationParser {
     }
     if (!intJoin.hasJoinColumns()) {
       // define foreign key columns
-      BeanProperty[] localIds = localTable.getIdProperties();
-      for (BeanProperty localId : localIds) {
+      BeanProperty localId = localTable.getIdProperty();
+      if (localId != null) {
         // add the source to intersection join columns
         String fkCol = localTableName + "_" + localId.getDbColumn();
         intJoin.addJoinColumn(new DeployTableJoinColumn(localId.getDbColumn(), namingConvention.getColumnFromProperty(null, fkCol)));
@@ -257,8 +392,8 @@ class AnnotationAssocManys extends AnnotationParser {
 
     if (!destJoin.hasJoinColumns()) {
       // define inverse foreign key columns
-      BeanProperty[] otherIds = otherTable.getIdProperties();
-      for (BeanProperty otherId : otherIds) {
+      BeanProperty otherId = otherTable.getIdProperty();
+      if (otherId != null) {
         // set the intersection to dest table join columns
         final String fkCol = otherTableName + "_" + otherId.getDbColumn();
         destJoin.addJoinColumn(new DeployTableJoinColumn(namingConvention.getColumnFromProperty(null, fkCol), otherId.getDbColumn()));

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationAssocOnes.java

@@ -41,8 +41,8 @@ public class AnnotationAssocOnes extends AnnotationParser {
   /**
    * Create with the deploy Info.
    */
-  AnnotationAssocOnes(DeployBeanInfo<?> info, boolean javaxValidationAnnotations, BeanDescriptorManager factory) {
-    super(info, javaxValidationAnnotations);
+  AnnotationAssocOnes(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig, BeanDescriptorManager factory) {
+    super(info, readConfig);
     this.factory = factory;
   }
 
@@ -92,9 +92,7 @@ public class AnnotationAssocOnes extends AnnotationParser {
     // May as well check for Id. Makes sense to me.
     Id id = get(prop, Id.class);
     if (id != null) {
-      prop.setEmbedded();
-      prop.setId();
-      prop.setNullable(false);
+      readIdAssocOne(prop);
     }
 
     DbForeignKey dbForeignKey = get(prop, DbForeignKey.class);
@@ -154,7 +152,7 @@ public class AnnotationAssocOnes extends AnnotationParser {
       }
     }
 
-    info.setBeanJoinType(prop, prop.isNullable());
+    prop.setJoinType(prop.isNullable());
 
     if (!prop.getTableJoin().hasJoinColumns() && beanTable != null) {
 

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationClass.java

@@ -23,6 +23,7 @@ import javax.persistence.AttributeOverride;
 import javax.persistence.Column;
 import javax.persistence.Embeddable;
 import javax.persistence.Entity;
+import javax.persistence.IdClass;
 import javax.persistence.NamedQuery;
 import javax.persistence.Table;
 import javax.persistence.UniqueConstraint;
@@ -41,25 +42,15 @@ public class AnnotationClass extends AnnotationParser {
 
   private final boolean disableL2Cache;
 
-  /**
-   * Create for normal early parse of class level annotations.
-   */
-  public AnnotationClass(DeployBeanInfo<?> info, boolean validationAnnotations, String asOfViewSuffix, String versionsBetweenSuffix, boolean disableL2Cache) {
-    super(info, validationAnnotations);
-    this.asOfViewSuffix = asOfViewSuffix;
-    this.versionsBetweenSuffix = versionsBetweenSuffix;
-    this.disableL2Cache = disableL2Cache;
-  }
-
   /**
    * Create to parse AttributeOverride annotations which is run last
    * after all the properties/fields have been parsed fully.
    */
-  public AnnotationClass(DeployBeanInfo<?> info) {
-    super(info, false);
-    this.asOfViewSuffix = null;
-    this.versionsBetweenSuffix = null;
-    this.disableL2Cache = false;
+  public AnnotationClass(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig) {
+    super(info, readConfig);
+    this.asOfViewSuffix = readConfig.getAsOfViewSuffix();
+    this.versionsBetweenSuffix = readConfig.getVersionsBetweenSuffix();
+    this.disableL2Cache = readConfig.isDisableL2Cache();
   }
 
   /**
@@ -127,6 +118,11 @@ public class AnnotationClass extends AnnotationParser {
       }
     }
 
+    IdClass idClass = AnnotationUtil.findAnnotationRecursive(cls, IdClass.class);
+    if (idClass != null) {
+      descriptor.setIdClass(idClass.value());
+    }
+
     Embeddable embeddable = AnnotationUtil.findAnnotationRecursive(cls, Embeddable.class);
     if (embeddable != null) {
       descriptor.setEntityType(EntityType.EMBEDDED);

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationFields.java

@@ -91,14 +91,11 @@ public class AnnotationFields extends AnnotationParser {
    */
   private FetchType defaultLobFetchType = FetchType.LAZY;
 
-  public AnnotationFields(GeneratedPropertyFactory generatedPropFactory, DeployBeanInfo<?> info,
-                          boolean javaxValidationAnnotations, boolean jacksonAnnotationsPresent, boolean eagerFetchLobs) {
-
-    super(info, javaxValidationAnnotations);
-    this.jacksonAnnotationsPresent = jacksonAnnotationsPresent;
-    this.generatedPropFactory = generatedPropFactory;
-
-    if (eagerFetchLobs) {
+  AnnotationFields(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig) {
+    super(info, readConfig);
+    this.jacksonAnnotationsPresent = readConfig.isJacksonAnnotations();
+    this.generatedPropFactory = readConfig.getGeneratedPropFactory();
+    if (readConfig.isEagerFetchLobs()) {
       defaultLobFetchType = FetchType.EAGER;
     }
   }
@@ -127,8 +124,7 @@ public class AnnotationFields extends AnnotationParser {
 
     Id id = get(prop, Id.class);
     if (id != null) {
-      prop.setId();
-      prop.setNullable(false);
+      readIdAssocOne(prop);
     }
 
     EmbeddedId embeddedId = get(prop, EmbeddedId.class);
@@ -211,7 +207,7 @@ public class AnnotationFields extends AnnotationParser {
 
     Id id = get(prop, Id.class);
     if (id != null) {
-      readId(prop);
+      readIdScalar(prop);
     }
 
     // determine the JDBC type using Lob/Temporal
@@ -517,18 +513,6 @@ public class AnnotationFields extends AnnotationParser {
     return util.createDataEncryptSupport(table, column);
   }
 
-  private void readId(DeployBeanProperty prop) {
-
-    prop.setId();
-    prop.setNullable(false);
-
-    if (prop.getPropertyType().equals(UUID.class)) {
-      if (descriptor.getIdGeneratorName() == null) {
-        descriptor.setUuidGenerator();
-      }
-    }
-  }
-
   private void readGenValue(GeneratedValue gen, DeployBeanProperty prop) {
 
     String genName = gen.generator();

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationParser.java

@@ -3,6 +3,7 @@ package io.ebeaninternal.server.deploy.parse;
 import io.ebeaninternal.server.deploy.BeanCascadeInfo;
 import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
 import io.ebeaninternal.server.deploy.meta.DeployBeanProperty;
+import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssoc;
 import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
 
 import javax.persistence.AttributeOverride;
@@ -11,6 +12,7 @@ import javax.persistence.Column;
 import javax.validation.groups.Default;
 import java.util.HashMap;
 import java.util.Set;
+import java.util.UUID;
 
 /**
  * Base class for reading deployment annotations.
@@ -25,9 +27,12 @@ public abstract class AnnotationParser extends AnnotationBase {
 
   protected final boolean validationAnnotations;
 
-  public AnnotationParser(DeployBeanInfo<?> info, boolean validationAnnotations) {
+  protected final ReadAnnotationConfig readConfig;
+
+  public AnnotationParser(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig) {
     super(info.getUtil());
-    this.validationAnnotations = validationAnnotations;
+    this.readConfig = readConfig;
+    this.validationAnnotations = readConfig.isJavaxValidationAnnotations();
     this.info = info;
     this.beanType = info.getDescriptor().getBeanType();
     this.descriptor = info.getDescriptor();
@@ -39,6 +44,36 @@ public abstract class AnnotationParser extends AnnotationBase {
   @Override
   public abstract void parse();
 
+  /**
+   * Read the Id annotation on an embeddedId.
+   */
+  protected void readIdAssocOne(DeployBeanPropertyAssoc<?> prop) {
+    prop.setNullable(false);
+    if (prop.isIdClass()) {
+      prop.setImportedPrimaryKey();
+    } else {
+      prop.setId();
+      prop.setEmbedded();
+    }
+  }
+
+  /**
+   * Read the Id annotation on scalar property.
+   */
+  protected void readIdScalar(DeployBeanProperty prop) {
+    prop.setNullable(false);
+    if (prop.isIdClass()) {
+      prop.setImportedPrimaryKey();
+    } else {
+      prop.setId();
+      if (prop.getPropertyType().equals(UUID.class)) {
+        if (descriptor.getIdGeneratorName() == null) {
+          descriptor.setUuidGenerator();
+        }
+      }
+    }
+  }
+
   /**
    * Helper method to set cascade types to the CascadeInfo on BeanProperty.
    */

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationSql.java

@@ -7,10 +7,10 @@ import io.ebeaninternal.server.deploy.BeanDescriptor;
 /**
  * Read the class level deployment annotations.
  */
-public class AnnotationSql extends AnnotationParser {
+class AnnotationSql extends AnnotationParser {
 
-  public AnnotationSql(DeployBeanInfo<?> info, boolean javaxValidationAnnotations) {
-    super(info, javaxValidationAnnotations);
+  AnnotationSql(DeployBeanInfo<?> info, ReadAnnotationConfig readConfig) {
+    super(info, readConfig);
   }
 
   @Override

src/main/java/io/ebeaninternal/server/deploy/parse/DeployBeanInfo.java

@@ -3,7 +3,6 @@ package io.ebeaninternal.server.deploy.parse;
 import io.ebean.RawSql;
 import io.ebeaninternal.server.deploy.TableJoin;
 import io.ebeaninternal.server.deploy.meta.DeployBeanDescriptor;
-import io.ebeaninternal.server.deploy.meta.DeployBeanPropertyAssocOne;
 import io.ebeaninternal.server.deploy.meta.DeployTableJoin;
 import io.ebeaninternal.server.query.SqlJoinType;
 import io.ebeaninternal.server.rawsql.SpiRawSql;
@@ -70,15 +69,6 @@ public class DeployBeanInfo<T> {
     return tableJoin;
   }
 
-  /**
-   * Set a the join alias for a assoc one property.
-   */
-  public void setBeanJoinType(DeployBeanPropertyAssocOne<?> beanProp, boolean outerJoin) {
-
-    DeployTableJoin tableJoin = beanProp.getTableJoin();
-    tableJoin.setType(outerJoin ? SqlJoinType.OUTER : SqlJoinType.INNER);
-  }
-
   /**
    * Add named RawSql from ebean.xml.
    */

src/main/java/io/ebeaninternal/server/deploy/parse/DeployCreateProperties.java

@@ -213,7 +213,6 @@ public class DeployCreateProperties {
     } catch (NullPointerException e) {
       logger.debug("expected non-scalar type {}", e.getMessage());
     }
-    // TODO: Handle Collection of CompoundType and Embedded Type
     return new DeployBeanPropertyAssocMany(desc, targetType, manyType);
   }
 

src/main/java/io/ebeaninternal/server/deploy/parse/DeployInherit.java

@@ -123,11 +123,14 @@ public class DeployInherit {
       info.setColumnDefn(da.columnDefinition());
     }
 
-    DiscriminatorValue dv = AnnotationUtil.findAnnotation(cls, DiscriminatorValue.class); // do not search recursive
-    if (dv != null) {
-      info.setDiscriminatorValue(dv.value());
+    if (!info.isAbstract()) {
+      DiscriminatorValue dv = AnnotationUtil.findAnnotation(cls, DiscriminatorValue.class); // do not search recursive
+      if (dv != null) {
+        info.setDiscriminatorValue(dv.value());
+      } else {
+        info.setDiscriminatorValue(cls.getSimpleName());
+      }
     }
-
     return info;
   }