[maven-release-plugin] prepare release ebean-10.4.5

* ADD: more test classes for Softdelete and History

* update reference models after adding test classes

* DbMigration:Improved History generation for sqlserver

* FIX: When DB supports Sql2011 platform, we must not alter the history-table (as this is handled by DB itself)

* DbMigration: When dropping a table, drop the sequence also.

* DbMigration: dropColumn is handled by platformDdl now, as SqlServerDdl needs to delete dependent objects (default constraints...) first

* FIX: DbMigration is not executed on history table

* DbMigration: can drop comment now.

* No effective code change: completed ObjectFactory / fixed imports

* FIX: drop table comment

* Committed the reference models

.travis.yml

@@ -1,3 +1,4 @@
+dist: trusty
 sudo: required
 language: java
 jdk:
@@ -7,7 +8,7 @@ git:
   depth: 3
 
 addons:
-  postgresql: "9.4"
+  postgresql: "9.6"
 
 services:
   - postgresql

howto-test.md

@@ -0,0 +1,152 @@
+This is a short description how to run tests
+============================================
+
+Run tests from maven
+--------------------
+
+Just type `mvn test` - it will run the whole test suite with the settings
+from `src/test/resources/ebean.properties`. 
+
+Run tests from eclipse
+----------------------
+
+Running tests requires, that the classes are enhanced. By default, the 
+`BaseTestCase` tries to load the enhancer-agent in a very early stage. This 
+also works for most test cases, but it does not work if you try to run a 
+complete test-suite, as classes that are loaded before the enhancer-agent 
+kicks in will not get enhanced. To solve this problem, you need either the
+[Eclipse-Enhancer-Plugin](https://github.com/ebean-orm-tools/ebean-eclipse-enhancer) 
+or add the agent to your JVM arguments (Preferences->Installed JREs) or to
+your run configuration: 
+`-javaagent:<USER_HOME>/.m2/repository/io/ebean/ebean-agent/<VERSION>/ebean-agent-<VERSION>.jar=debug=0`
+
+
+Platform Tests
+==============
+
+By default, the `h2` platform is used. To test a different platform, add 
+`-Ddatasource.default=xxx` to your maven command or JVM arguments.
+
+'h2' platform
+-------------
+
+Reqires no setup
+
+run: `mvn clean test`
+
+Current status: PASS
+Tests run: 1986, Failures: 0, Errors: 0, Skipped: 16
+
+'pg' platform
+-------------
+
+Reqirements
+- a locally installed PostgreSQL server with PostGis.
+- Create a user "unit" with password "unit" and a database "unit"
+- Give the user all permissions to that db
+
+run: `mvn clean test -Ddatasource.default=pg`
+
+Current status: PASS
+Tests run: 1986, Failures: 0, Errors: 0, Skipped: 16
+
+
+'mysql' platform
+-------------
+
+Reqirements
+- a locally installed MySQL server.
+- Create a user "unit" with password "unit" and a database "unit"
+- Give the user all permissions to that db
+
+run: `mvn clean test -Ddatasource.default=mysql`
+
+Current status: FAIL
+Tests run: 1986, Failures: 2, Errors: 4, Skipped: 16
+
+
+
+'sqlserver' platform
+--------------------
+
+Reqires an installed sqlserver - e.g. https://hub.docker.com/r/microsoft/mssql-server-linux/
+
+- Create a user "ebean" with password "ebean" and a database "ebean_unittest"
+- Adjust the connection string and/or username in ebean.properties
+  
+run: `mvn clean test -Ddatasource.default=mssql`
+
+Current status: FAIL
+Tests run: 1986, Failures: 19, Errors: 43, Skipped: 16
+
+
+
+'oracle' platform
+-----------------
+
+Reqires a locally installed Oracle server.
+- Create a user "unit" with password "unit" with all permissions
+- The test wirtes directly to the "xe" SID - so do not use a productive server!
+- As the Oracle JDBC driver is only available on an oracle repository,
+  you need a special maven setup as described [here](http://docs.oracle.com/middleware/1213/core/MAVEN/config_maven_repo.htm#MAVEN9010)
+  
+run: `mvn clean test -Ddatasource.default=ora -Poracle`
+
+Current status: FAIL
+Tests run: 1986, Failures: 17, Errors: 34, Skipped: 16
+
+
+
+'db2' platform
+--------------
+
+Reqires a locally installed DB2 Express-C server.
+- Create a user "unit" with password "unit" with all permissions
+- Install the db2jcc4 driver (see pom.xml)
+
+run: `mvn clean test -Ddatasource.default=db2 -Pdb2`
+
+Current status: FAIL
+Tests run: 1986, Failures: 33, Errors: 26, Skipped: 16
+
+
+'sqlite' platform
+-----------------
+
+Reqires no setup
+
+run: `mvn clean test -Ddatasource.default=sqlite`
+
+Current status: FAIL
+Tests run: 1986, Failures: 24, Errors: 86, Skipped: 16
+
+After some time, the db locks up, every test takes 3 seconds and fails with 
+"the database file is locked"
+
+
+
+'hsqldb' platform
+-----------------
+
+Reqires no setup
+
+run: `mvn clean test -Ddatasource.default=hsqldb`
+
+Current status: FAIL
+Tests run: 1980, Failures: 3, Errors: 657, Skipped: 16
+
+
+@Rob FYI
+The problem is https://sourceforge.net/p/hsqldb/bugs/1364/
+In `InsertHandler.getPstmt` the `meta.getIdentityDbColumns()` contains
+'id' in lowercase. Changing that to uppercase gives me this result:
+`Tests run: 1986, Failures: 2, Errors: 18, Skipped: 16`
+(as quick hack I added temporary a toUpperCase to BindableIdScalar.getIdentityColumn)
+
+
+'sqlanywhere' platform
+----------------------
+
+TODO: not yet tested
+
+

pom.xml

@@ -9,7 +9,7 @@
 
   <groupId>io.ebean</groupId>
   <artifactId>ebean</artifactId>
-  <version>10.2.1</version>
+  <version>10.4.5</version>
   <packaging>jar</packaging>
 
   <name>ebean</name>
@@ -17,9 +17,59 @@
 
   <scm>
     <developerConnection>scm:git:git@github.com:ebean-orm/ebean.git</developerConnection>
-    <tag>ebean-10.2.1</tag>
+    <tag>ebean-10.4.5</tag>
   </scm>
 
+  <profiles>
+    <profile>
+      <!-- Note: to use this profile, you need credentials for the oracle repository in your
+        settings.xml as described here:
+        http://docs.oracle.com/middleware/1213/core/MAVEN/config_maven_repo.htm#MAVEN9010 -->
+      <id>oracle</id>
+      <dependencies>
+        <dependency>
+          <groupId>com.oracle.jdbc</groupId>
+          <artifactId>ojdbc8</artifactId>
+          <version>12.2.0.1</version>
+          <scope>test</scope>
+        </dependency>
+      </dependencies>
+      <repositories>
+        <repository>
+          <id>maven.oracle.com</id>
+          <releases>
+            <enabled>true</enabled>
+          </releases>
+          <snapshots>
+            <enabled>false</enabled>
+          </snapshots>
+          <url>https://maven.oracle.com</url>
+          <layout>default</layout>
+        </repository>
+      </repositories>
+    </profile>
+    <profile>
+      <!-- Note: to use this profile, you need to download manually the db2jcc4 driver.
+        After that, install it into your local maven repository:
+
+        mvn install:install-file \
+          -Dfile=db2jcc4.jar \
+          -DgroupId=com.ibm.jdbc \
+          -DartifactId=db2jcc4 \
+          -Dversion=4.23.42 \
+          -Dpackaging=jar
+      -->
+      <id>db2</id>
+      <dependencies>
+        <dependency>
+          <groupId>com.ibm.jdbc</groupId>
+          <artifactId>db2jcc4</artifactId>
+          <version>4.23.42</version>
+          <scope>test</scope>
+        </dependency>
+      </dependencies>
+    </profile>
+  </profiles>
   <dependencies>
 
     <dependency>
@@ -37,7 +87,7 @@
     <dependency>
       <groupId>io.ebean</groupId>
       <artifactId>ebean-annotation</artifactId>
-      <version>2.2</version>
+      <version>2.4</version>
     </dependency>
 
     <dependency>
@@ -49,7 +99,7 @@
     <dependency>
       <groupId>org.avaje</groupId>
       <artifactId>avaje-datasource</artifactId>
-      <version>2.1.1</version>
+      <version>2.1.2</version>
     </dependency>
 
     <dependency>
@@ -61,13 +111,13 @@
     <dependency>
       <groupId>org.avaje</groupId>
       <artifactId>avaje-classpath-scanner</artifactId>
-      <version>2.2.2</version>
+      <version>2.2.4</version>
     </dependency>
 
     <dependency>
       <groupId>io.ebean</groupId>
-      <artifactId>ebean-dbmigration</artifactId>
-      <version>10.1.4</version>
+      <artifactId>ebean-migration</artifactId>
+      <version>10.2.1</version>
     </dependency>
 
     <dependency>
@@ -86,14 +136,14 @@
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-core</artifactId>
-      <version>2.6.5</version>
+      <version>2.9.0</version>
     </dependency>
 
     <!-- provided scope for JsonNode support -->
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-databind</artifactId>
-      <version>2.6.5</version>
+      <version>2.9.0</version>
       <scope>provided</scope>
     </dependency>
 
@@ -130,7 +180,7 @@
     <dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
-      <version>9.4.1212.jre7</version>
+      <version>9.4.1212</version>
       <scope>provided</scope>
     </dependency>
 
@@ -160,7 +210,7 @@
     <dependency>
       <groupId>io.ebean</groupId>
       <artifactId>ebean-agent</artifactId>
-      <version>10.1.7</version>
+      <version>10.4.1</version>
       <scope>test</scope>
     </dependency>
 
@@ -187,10 +237,18 @@
       <scope>test</scope>
     </dependency>
 
+    <dependency>
+      <groupId>com.microsoft.sqlserver</groupId>
+      <artifactId>mssql-jdbc</artifactId>
+      <version>6.1.3.jre8-preview</version>
+      <scope>test</scope>
+    </dependency>
+
     <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
-      <version>6.0.5</version>
+      <!-- Do not upgrade to 6.0.6: https://bugs.mysql.com/bug.php?id=82896 -->
+      <version>5.1.43</version>
       <scope>test</scope>
     </dependency>
 
@@ -225,7 +283,7 @@
       <plugin>
         <groupId>io.ebean</groupId>
         <artifactId>ebean-maven-plugin</artifactId>
-        <version>10.1.7</version>
+        <version>10.4.1</version>
         <executions>
           <execution>
             <id>test</id>

src/main/java/io/ebean/AcquireLockException.java

@@ -10,6 +10,7 @@ import javax.persistence.PessimisticLockException;
  * </p>
  */
 public class AcquireLockException extends PessimisticLockException {
+  private static final long serialVersionUID = -8585962352965876691L;
 
   /**
    * Create with a message and cause.

src/main/java/io/ebean/DRawSqlColumnsParser.java

@@ -2,6 +2,7 @@ package io.ebean;
 
 import io.ebean.RawSql.ColumnMapping;
 
+import java.util.regex.Pattern;
 import javax.persistence.PersistenceException;
 import java.util.ArrayList;
 
@@ -10,6 +11,8 @@ import java.util.ArrayList;
  */
 final class DRawSqlColumnsParser {
 
+  private static final Pattern COLINFO_SPLIT = Pattern.compile("\\s(?=[^\\)]*(?:\\(|$))");
+
   private final int end;
 
   private final String sqlSelect;
@@ -44,7 +47,7 @@ final class DRawSqlColumnsParser {
     String colInfo = sqlSelect.substring(start, pos++);
     colInfo = colInfo.trim();
 
-    String[] split = colInfo.split("\\s(?=[^\\)]*(?:\\(|$))");
+    String[] split = COLINFO_SPLIT.split(colInfo);
     if (split.length > 1) {
       ArrayList<String> tmp = new ArrayList<>(split.length);
       for (String aSplit : split) {

src/main/java/io/ebean/DataIntegrityException.java

@@ -6,6 +6,7 @@ import javax.persistence.PersistenceException;
  * Thrown when a foreign key constraint is enforced.
  */
 public class DataIntegrityException extends PersistenceException {
+  private static final long serialVersionUID = -6740171949170180970L;
 
   /**
    * Create with a message and cause.

src/main/java/io/ebean/DocumentStore.java

@@ -56,7 +56,7 @@ public interface DocumentStore {
    * Return the bean by fetching it's content from the document store.
    * If the document is not found null is returned.
    * <p>
-   * Typically this is called indirectly by findUnique() on the query.
+   * Typically this is called indirectly by findOne() on the query.
    * </p>
    * <pre>{@code
    *
@@ -64,7 +64,7 @@ public interface DocumentStore {
    *   server.find(Customer.class)
    *     .setUseDocStore(true)
    *     .setId(42)
-   *     .findUnique();
+   *     .findOne();
    *
    * }</pre>
    */

src/main/java/io/ebean/DuplicateKeyException.java

@@ -4,6 +4,7 @@ package io.ebean;
  * Thrown when a duplicate is attempted on a unique constraint.
  */
 public class DuplicateKeyException extends DataIntegrityException {
+  private static final long serialVersionUID = -4771932723285724817L;
 
   /**
    * Create with a message and cause.

src/main/java/io/ebean/Ebean.java

@@ -14,6 +14,7 @@ import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
@@ -154,7 +155,7 @@ public final class Ebean {
         } else {
           // look to see if there is a default server defined
           String defaultName = PrimaryServer.getDefaultServerName();
-          logger.debug("defaultName:" + defaultName);
+          logger.debug("defaultName:{}", defaultName);
           if (defaultName != null && !defaultName.trim().isEmpty()) {
             defaultServer = getWithCreate(defaultName.trim());
           }
@@ -289,7 +290,7 @@ public final class Ebean {
   }
 
   /**
-   * Backdoor for registering a mock implementation of EbeanServer as the default  server.
+   * Backdoor for registering a mock implementation of EbeanServer as the default server.
    */
   protected static EbeanServer mock(String name, EbeanServer server, boolean defaultServer) {
     EbeanServer originalPrimaryServer = serverMgr.defaultServer;
@@ -371,9 +372,10 @@ public final class Ebean {
   /**
    * Start a transaction typically specifying REQUIRES_NEW or REQUIRED semantics.
    * <p>
-   * Note that this provides an try finally alternative to using {@link #execute(TxScope, TxCallable)} or
-   * {@link #execute(TxScope, TxRunnable)}.
+   * Note that this provides an try finally alternative to using {@link #executeCall(TxScope, Callable)} or
+   * {@link #execute(TxScope, Runnable)}.
    * </p>
+   *
    * <h3>REQUIRES_NEW example:</h3>
    * <pre>{@code
    * // Start a new transaction. If there is a current transaction
@@ -822,7 +824,7 @@ public final class Ebean {
    * }</pre>
    * <p>
    * If you want more control over the query then you can use createQuery() and
-   * Query.findUnique();
+   * Query.findOne();
    * </p>
    * <pre>{@code
    *
@@ -843,7 +845,8 @@ public final class Ebean {
    *
    *   // traverse the object graph...
    *
-   *   Order order = query.findUnique();
+   *   Order order = query.findOne();
+   *
    *   Customer customer = order.getCustomer();
    *   Address shippingAddress = customer.getShippingAddress();
    *   List<OrderDetail> details = order.getDetails();
@@ -959,7 +962,7 @@ public final class Ebean {
    * predicates, order by, limits etc.
    * </p>
    * <p>
-   * You then use findList(), findSet(), findMap() and findUnique() to execute
+   * You then use findList(), findSet(), findMap() and findOne() to execute
    * the query and return the collection or bean.
    * </p>
    * <p>
@@ -991,7 +994,7 @@ public final class Ebean {
    *   Query<Order> query = Ebean.createQuery(Order.class, eql);
    *   query.setParameter("orderId", 2);
    *
-   *   Order order = query.findUnique();
+   *   Order order = query.findOne();
    *
    *   // This is the same as:
    *
@@ -1000,7 +1003,7 @@ public final class Ebean {
    *     .fetch("details")
    *     .fetch("detail.product", "name")
    *     .setId(2)
-   *     .findUnique();
+   *     .findOne();
    *
    * }</pre>
    *
@@ -1181,20 +1184,20 @@ public final class Ebean {
    *
    * }</pre>
    */
-  public static void execute(TxScope scope, TxRunnable r) {
+  public static void execute(TxScope scope, Runnable r) {
     serverMgr.getDefaultServer().execute(scope, r);
   }
 
   /**
-   * Execute a TxRunnable in a Transaction with the default scope.
+   * Execute a Runnable in a Transaction with the default scope.
    * <p>
    * The default scope runs with REQUIRED and by default will rollback on any
    * exception (checked or runtime).
    * </p>
    * <pre>{@code
    *
-   *   Ebean.execute(new TxRunnable() {
-   *     public void run() {
+   *   Ebean.execute(() -> {
+   *
    *       User u1 = Ebean.find(User.class, 1);
    *       User u2 = Ebean.find(User.class, 2);
    *
@@ -1203,17 +1206,17 @@ public final class Ebean {
    *
    *       Ebean.save(u1);
    *       Ebean.save(u2);
-   *     }
+   *
    *   });
    *
    * }</pre>
    */
-  public static void execute(TxRunnable r) {
+  public static void execute(Runnable r) {
     serverMgr.getDefaultServer().execute(r);
   }
 
   /**
-   * Execute a TxCallable in a Transaction with an explicit scope.
+   * Execute a Callable in a Transaction with an explicit scope.
    * <p>
    * The scope can control the transaction type, isolation and rollback
    * semantics.
@@ -1223,7 +1226,7 @@ public final class Ebean {
    *   // set specific transactional scope settings
    *   TxScope scope = TxScope.requiresNew().setIsolation(TxIsolation.SERIALIZABLE);
    *
-   *   Ebean.execute(scope, new TxCallable<String>() {
+   *   Ebean.executeCall(scope, new Callable<String>() {
    * 	   public String call() {
    * 		   User u1 = Ebean.find(User.class, 1);
    * 		   ...
@@ -1233,12 +1236,20 @@ public final class Ebean {
    *
    * }</pre>
    */
-  public static <T> T execute(TxScope scope, TxCallable<T> c) {
-    return serverMgr.getDefaultServer().execute(scope, c);
+  public static <T> T executeCall(TxScope scope, Callable<T> c) {
+    return serverMgr.getDefaultServer().executeCall(scope, c);
   }
 
   /**
-   * Execute a TxCallable in a Transaction with the default scope.
+   * Deprecated - please migrate to executeCall().
+   */
+  @Deprecated
+  public static <T> T execute(TxScope scope, TxCallable<T> c) {
+    return serverMgr.getDefaultServer().executeCall(scope, c);
+  }
+
+  /**
+   * Execute a Callable in a Transaction with the default scope.
    * <p>
    * The default scope runs with REQUIRED and by default will rollback on any
    * exception (checked or runtime).
@@ -1249,8 +1260,8 @@ public final class Ebean {
    * </p>
    * <pre>{@code
    *
-   *   Ebean.execute(new TxCallable<String>() {
-   *     public String call() {
+   *   Ebean.executeCall(() -> {
+   *
    *       User u1 = Ebean.find(User.class, 1);
    *       User u2 = Ebean.find(User.class, 2);
    *
@@ -1261,11 +1272,19 @@ public final class Ebean {
    *       Ebean.save(u2);
    *
    *       return u1.getEmail();
-   *     }
+   *
    *   });
    *
    * }</pre>
    */
+  public static <T> T executeCall(Callable<T> c) {
+    return serverMgr.getDefaultServer().executeCall(c);
+  }
+
+  /**
+   * Deprecated - please migrate to executeCall().
+   */
+  @Deprecated
   public static <T> T execute(TxCallable<T> c) {
     return serverMgr.getDefaultServer().execute(c);
   }

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

@@ -14,7 +14,9 @@ import javax.persistence.PersistenceException;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
+import java.util.concurrent.Callable;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 
@@ -237,7 +239,7 @@ public interface EbeanServer {
    *   Query<Order> query = Ebean.createQuery(Order.class, ormQuery);
    *   query.setParameter("orderId", 2);
    *
-   *   Order order = query.findUnique();
+   *   Order order = query.findOne();
    *
    *   // This is the same as:
    *
@@ -246,7 +248,7 @@ public interface EbeanServer {
    *     .fetch("details")
    *     .fetch("detail.product", "name")
    *     .setId(2)
-   *     .findUnique();
+   *     .findOne();
    *
    * }</pre>
    *
@@ -264,7 +266,7 @@ public interface EbeanServer {
    * predicates, order by, limits etc.
    * </p>
    * <p>
-   * You then use findList(), findSet(), findMap() and findUnique() to execute
+   * You then use findList(), findSet(), findMap() and findOne() to execute
    * the query and return the collection or bean.
    * </p>
    * <p>
@@ -284,7 +286,7 @@ public interface EbeanServer {
    *     .fetch("details")
    *     .fetch("detail.product", "name")
    *     .setId(2)
-   *     .findUnique();
+   *     .findOne();
    *
    *   // find some new orders ... with firstRow/maxRows
    *   List<Order> orders =
@@ -693,7 +695,7 @@ public interface EbeanServer {
    * <p>
    * <p>
    * If you want more control over the query then you can use createQuery() and
-   * Query.findUnique();
+   * Query.findOne();
    * </p>
    * <p>
    * <pre>{@code
@@ -713,7 +715,7 @@ public interface EbeanServer {
    *   query.fetch("details.product", "name");
    *
    *
-   *   Order order = query.findUnique();
+   *   Order order = query.findOne();
    *
    *   // traverse the object graph...
    *
@@ -1066,7 +1068,7 @@ public interface EbeanServer {
    * This will throw a NonUniqueResultException if the query finds more than one result.
    * </p>
    * <p>
-   * Generally you are able to use {@link Query#findUnique()} rather than
+   * Generally you are able to use {@link Query#findOne()} rather than
    * explicitly calling this method. You could use this method if you wish to
    * explicitly control the transaction used for the query.
    * </p>
@@ -1076,9 +1078,25 @@ public interface EbeanServer {
    * @param transaction the transaction to use (can be null).
    * @return the list of fetched beans.
    * @throws NonUniqueResultException if more than one result was found
-   * @see Query#findUnique()
+   * @see Query#findOne()
    */
   @Nullable
+  <T> T findOne(Query<T> query, Transaction transaction);
+
+  /**
+   * Similar to findOne() but returns an Optional (rather than nullable).
+   */
+  <T> Optional<T> findOneOrEmpty(Query<T> query, Transaction transaction);
+
+  /**
+   * Deprecated - please migrate to findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Deprecated
+  @Nullable
   <T> T findUnique(Query<T> query, Transaction transaction);
 
   /**
@@ -1150,7 +1168,7 @@ public interface EbeanServer {
    * result.
    * </p>
    * <p>
-   * Generally you are able to use {@link SqlQuery#findUnique()} rather than
+   * Generally you are able to use {@link SqlQuery#findOne()} rather than
    * explicitly calling this method. You could use this method if you wish to
    * explicitly control the transaction used for the query.
    * </p>
@@ -1158,9 +1176,20 @@ public interface EbeanServer {
    * @param query       the query to execute.
    * @param transaction the transaction to use (can be null).
    * @return the fetched MapBean or null if none was found.
-   * @see SqlQuery#findUnique()
+   * @see SqlQuery#findOne()
    */
   @Nullable
+  SqlRow findOne(SqlQuery query, Transaction transaction);
+
+  /**
+   * Deprecated - please migrate to findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Deprecated
+  @Nullable
   SqlRow findUnique(SqlQuery query, Transaction transaction);
 
   /**
@@ -1559,7 +1588,7 @@ public interface EbeanServer {
   int execute(CallableSql callableSql, Transaction transaction);
 
   /**
-   * Execute a TxRunnable in a Transaction with an explicit scope.
+   * Execute a Runnable in a Transaction with an explicit scope.
    * <p>
    * The scope can control the transaction type, isolation and rollback
    * semantics.
@@ -1570,7 +1599,7 @@ public interface EbeanServer {
    *   // set specific transactional scope settings
    *   TxScope scope = TxScope.requiresNew().setIsolation(TxIsolation.SERIALIZABLE);
    *
-   *   ebeanServer.execute(scope, new TxRunnable() {
+   *   ebeanServer.execute(scope, new Runnable() {
    * 	   public void run() {
    * 		   User u1 = Ebean.find(User.class, 1);
    * 		   ...
@@ -1579,10 +1608,10 @@ public interface EbeanServer {
    *
    * }</pre>
    */
-  void execute(TxScope scope, TxRunnable runnable);
+  void execute(TxScope scope, Runnable runnable);
 
   /**
-   * Execute a TxRunnable in a Transaction with the default scope.
+   * Execute a Runnable in a Transaction with the default scope.
    * <p>
    * The default scope runs with REQUIRED and by default will rollback on any
    * exception (checked or runtime).
@@ -1590,8 +1619,8 @@ public interface EbeanServer {
    * <p>
    * <pre>{@code
    *
-   *    ebeanServer.execute(new TxRunnable() {
-   *      public void run() {
+   *    ebeanServer.execute(() -> {
+   *
    *        User u1 = ebeanServer.find(User.class, 1);
    *        User u2 = ebeanServer.find(User.class, 2);
    *
@@ -1600,12 +1629,12 @@ public interface EbeanServer {
    *
    *        ebeanServer.save(u1);
    *        ebeanServer.save(u2);
-   *      }
+   *
    *    });
    *
    * }</pre>
    */
-  void execute(TxRunnable runnable);
+  void execute(Runnable runnable);
 
   /**
    * Execute a TxCallable in a Transaction with an explicit scope.
@@ -1619,7 +1648,7 @@ public interface EbeanServer {
    *   // set specific transactional scope settings
    *   TxScope scope = TxScope.requiresNew().setIsolation(TxIsolation.SERIALIZABLE);
    *
-   *   ebeanServer.execute(scope, new TxCallable<String>() {
+   *   ebeanServer.executeCall(scope, new Callable<String>() {
    * 	   public String call() {
    * 		   User u1 = ebeanServer.find(User.class, 1);
    * 		   ...
@@ -1629,22 +1658,24 @@ public interface EbeanServer {
    *
    * }</pre>
    */
+  <T> T executeCall(TxScope scope, Callable<T> callable);
+
+  /**
+   * Deprecated - please migrate to executeCall().
+   */
+  @Deprecated
   <T> T execute(TxScope scope, TxCallable<T> callable);
 
   /**
-   * Execute a TxCallable in a Transaction with the default scope.
+   * Execute a Callable in a Transaction with the default scope.
    * <p>
    * The default scope runs with REQUIRED and by default will rollback on any
    * exception (checked or runtime).
    * </p>
    * <p>
-   * This is basically the same as TxRunnable except that it returns an Object
-   * (and you specify the return type via generics).
-   * </p>
-   * <p>
    * <pre>{@code
    *
-   *   ebeanServer.execute(new TxCallable<String>() {
+   *   ebeanServer.executeCall(new Callable<String>() {
    *     public String call() {
    *       User u1 = ebeanServer.find(User.class, 1);
    *       User u2 = ebeanServer.find(User.class, 2);
@@ -1661,6 +1692,12 @@ public interface EbeanServer {
    *
    * }</pre>
    */
+  <T> T executeCall(Callable<T> callable);
+
+  /**
+   * Deprecated - please migrate to executeCall().
+   */
+  @Deprecated
   <T> T execute(TxCallable<T> callable);
 
   /**

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

@@ -7,7 +7,6 @@ import io.ebean.search.TextQueryString;
 import io.ebean.search.TextSimple;
 
 import java.util.Collection;
-import java.util.List;
 import java.util.Map;
 
 /**
@@ -308,9 +307,9 @@ public interface ExpressionFactory {
   Expression idIn(Object... idValues);
 
   /**
-   * Id IN a list of Id values.
+   * Id IN a collection of Id values.
    */
-  Expression idIn(List<?> idList);
+  Expression idIn(Collection<?> idCollection);
 
   /**
    * All Equal - Map containing property names and their values.

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

@@ -12,6 +12,7 @@ import java.sql.Timestamp;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -263,9 +264,25 @@ public interface ExpressionList<T> {
    * </p>
    *
    * @throws NonUniqueResultException if more than one result was found
-   * @see Query#findUnique()
+   * @see Query#findOne()
    */
   @Nullable
+  T findOne();
+
+  /**
+   * Execute the query returning an optional bean.
+   */
+  Optional<T> findOneOrEmpty();
+
+  /**
+   * Deprecated - please migrate to findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Deprecated
+  @Nullable
   T findUnique();
 
   /**
@@ -820,9 +837,9 @@ public interface ExpressionList<T> {
   ExpressionList<T> idIn(Object... idValues);
 
   /**
-   * Id IN a list of id values.
+   * Id IN a collection of id values.
    */
-  ExpressionList<T> idIn(List<?> idValues);
+  ExpressionList<T> idIn(Collection<?> idValues);
 
   /**
    * Id Equal to - ID property is equal to the value.

src/main/java/io/ebean/Finder.java

@@ -27,7 +27,7 @@ import java.util.List;
  *   // Add your customer finder methods ...
  *
  *   public Customer byName(String name) {
- *     return query().eq("name", name).findUnique();
+ *     return query().eq("name", name).findOne();
  *   }
  *
  *   public List<Customer> findNew() {

src/main/java/io/ebean/LikeType.java

@@ -6,22 +6,22 @@ package io.ebean;
 public enum LikeType {
 
   /**
-   * You need to put in your own wildcards.
+   * You need to put in your own wildcards - no escaping is performed.
    */
   RAW,
 
   /**
-   * The % wildcard is added to the end of the search word.
+   * The % wildcard is added to the end of the search word and search word is escaped.
    */
   STARTS_WITH,
 
   /**
-   * The % wildcard is added to the beginning of the search word.
+   * The % wildcard is added to the beginning of the search word and search word is escaped.
    */
   ENDS_WITH,
 
   /**
-   * The % wildcard is added to the beginning and end of the search word.
+   * The % wildcard is added to the beginning and end of the search word and search word is escaped.
    */
   CONTAINS,
 

src/main/java/io/ebean/Query.java

@@ -6,6 +6,7 @@ import javax.persistence.NonUniqueResultException;
 import java.sql.Timestamp;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -830,7 +831,7 @@ public interface Query<T> {
    * Product product =
    *     ebeanServer.find(Product.class)
    *         .where().eq("sku", "aa113")
-   *         .findUnique();
+   *         .findOne();
    * ...
    * }</pre>
    * <p>
@@ -844,7 +845,7 @@ public interface Query<T> {
    *     ebeanServer.find(Order.class)
    *       .setId(1)
    *       .fetch("details")
-   *       .findUnique();
+   *       .findOne();
    *
    * // the order details were eagerly loaded
    * List<OrderDetail> details = order.getDetails();
@@ -854,6 +855,22 @@ public interface Query<T> {
    * @throws NonUniqueResultException if more than one result was found
    */
   @Nullable
+  T findOne();
+
+  /**
+   * Execute the query returning an optional bean.
+   */
+  Optional<T> findOneOrEmpty();
+
+  /**
+   * Deprecated - please migrate to findOne().
+   * <p>
+   * This proceeded findOne which was introduced to better match spring data.
+   * This will be deprecated at some future point.
+   * </p>
+   */
+  @Deprecated
+  @Nullable
   T findUnique();
 
   /**
@@ -1012,7 +1029,7 @@ public interface Query<T> {
   Query<T> setParameter(int position, Object value);
 
   /**
-   * Set the Id value to query. This is used with findUnique().
+   * Set the Id value to query. This is used with findOne().
    * <p>
    * You can use this to have further control over the query. For example adding
    * fetch joins.
@@ -1023,7 +1040,7 @@ public interface Query<T> {
    *     ebeanServer.find(Order.class)
    *     .setId(1)
    *     .fetch("details")
-   *     .findUnique();
+   *     .findOne();
    *
    * // the order details were eagerly fetched
    * List<OrderDetail> details = order.getDetails();

src/main/java/io/ebean/SqlQuery.java

@@ -2,6 +2,7 @@ package io.ebean;
 
 import java.io.Serializable;
 import java.util.List;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 
@@ -70,6 +71,17 @@ public interface SqlQuery extends Serializable {
    * PersistenceException.
    * </p>
    */
+  SqlRow findOne();
+
+  /**
+   * Execute the query returning an optional row.
+   */
+  Optional<SqlRow> findOneOrEmpty();
+
+  /**
+   * Deprecated - please migrate to findOne().
+   */
+  @Deprecated
   SqlRow findUnique();
 
   /**

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

@@ -129,6 +129,7 @@ public interface Transaction extends AutoCloseable {
   /**
    * Synonym for end() to support AutoClosable.
    */
+  @Override
   void close();
 
   /**

src/main/java/io/ebean/TxCallable.java

@@ -1,9 +1,13 @@
 package io.ebean;
 
+import java.util.concurrent.Callable;
+
 /**
+ * Deprecated - please migrate to just using Callable instead with executeCall().
+ *
  * Execute a TxCallable in a Transaction scope.
  * <p>
- * Use this with the {@link Ebean#execute(TxCallable)} method.
+ * Use this with the {@link Ebean#executeCall(Callable)} method.
  * </p>
  * <p>
  * Note that this is basically the same as TxRunnable except that it returns an
@@ -31,10 +35,9 @@ package io.ebean;
  * });
  *
  * }</pre>
- *
- * @see TxRunnable
  */
-public interface TxCallable<T> {
+@Deprecated
+public interface TxCallable<T> extends Callable<T> {
 
   /**
    * Execute the method within a transaction scope returning the result.

src/main/java/io/ebean/TxRunnable.java

@@ -1,12 +1,12 @@
 package io.ebean;
 
 /**
+ * Deprecated - please migrate to using just Runnable.
+ *
+ *
  * Execute a TxRunnable in a Transaction scope.
  * <p>
- * Use this with the {@link Ebean#execute(TxRunnable)} method.
- * </p>
- * <p>
- * See also {@link TxCallable}.
+ * Use this with the {@link Ebean#execute(Runnable)} method.
  * </p>
  * <p>
  * <pre>{@code
@@ -31,7 +31,8 @@ package io.ebean;
  *
  * @see TxCallable
  */
-public interface TxRunnable {
+@Deprecated
+public interface TxRunnable extends Runnable {
 
   /**
    * Run the method in a transaction sope.

src/main/java/io/ebean/annotation/Transactional.java

@@ -1,138 +0,0 @@
-package io.ebean.annotation;
-
-import io.ebean.TxIsolation;
-import io.ebean.TxType;
-import io.ebean.PersistBatch;
-
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-/**
- * Specify transaction scoping for a method.
- * <p>
- * <b><i> This is only supported if "Enhancement" is used via javaagent, ANT
- * task or IDE enhancement plugin etc. </i></b>
- * </p>
- * <p>
- * Note: Currently there are 3 known annotations that perform this role.
- * <ul>
- * <li>EJB's javax.ejb.TransactionAttribute</li>
- * <li>Spring's org.springframework.transaction.annotation.Transactional</li>
- * <li>and this one, Ebean's own Transactional</li>
- * </ul>
- * Spring created their one because the EJB annotation does not support features
- * such as isolation level and specifying rollbackOn, noRollbackOn exceptions.
- * This one exists for Ebean because I agree that the standard one is
- * insufficient and don't want to include a dependency on Spring.
- * </p>
- * <p>
- * The default behaviour of EJB (and hence Spring) is to NOT ROLLBACK on checked
- * exceptions. I find this very counter-intuitive. Ebean will provide a property
- * to set the default behaviour to rollback on any exception and optionally
- * change the setting to be consistent with EJB/Spring if people wish to do so.
- * </p>
- * <p>
- * <pre>{@code
- *
- *  // a normal class
- *  public class MySimpleUserService {
- *
- *    // this method is transactional automatically handling
- *    // transaction begin, commit and rollback etc
- *    @Transactional
- *    public void runInTrans() throws IOException {
- *
- *      // tasks performed within the transaction
- *      ...
- *      // find some objects
- *      Customer cust = ebeanServer.find(Customer.class, 42);
- *
- *      Order order = ...;
- *      ...
- *      // save some objects
- *      ebeanServer.save(customer);
- *      ebeanServer.save(order);
- *    }
- *
- * }</pre>
- */
-@Target({ElementType.METHOD, ElementType.TYPE})
-@Retention(RetentionPolicy.RUNTIME)
-public @interface Transactional {
-
-  /**
-   * The type of transaction scoping. Defaults to REQUIRED.
-   */
-  TxType type() default TxType.REQUIRED;
-
-  /**
-   * Persist batch mode for the transaction.
-   */
-  PersistBatch batch() default PersistBatch.INHERIT;
-
-  /**
-   * Persist batch mode for the request if not set on the transaction.
-   * <p>
-   * If batch is set to NONE then batchOnCascade can be set to INSERT or ALL
-   * and then each save(), delete(), insert(), update() request that cascades
-   * to child beans can use JDBC batch.
-   * </p>
-   */
-  PersistBatch batchOnCascade() default PersistBatch.INHERIT;
-
-  /**
-   * The batch size to use when using JDBC batch mode.
-   * <p>
-   * If unset this defaults to the value set in ServerConfig.
-   * </p>
-   */
-  int batchSize() default 0;
-
-  /**
-   * Set to false when we want to skip getting generatedKeys.
-   * <p>
-   * This is typically used in the case of large batch inserts where we get a
-   * performance benefit from not calling getGeneratedKeys (as we are going to
-   * insert a lot of rows and have no need for the Id values after the insert).
-   * </p>
-   */
-  boolean getGeneratedKeys() default true;
-
-  /**
-   * The transaction isolation level this transaction should have.
-   * <p>
-   * This will only be used if this scope creates the transaction. If the
-   * transaction has already started then this will currently be ignored (you
-   * could argue that it should throw an exception).
-   * </p>
-   */
-  TxIsolation isolation() default TxIsolation.DEFAULT;
-
-  /**
-   * Set this to true if the transaction should be only contain queries.
-   */
-  boolean readOnly() default false;
-
-  /**
-   * The name of the server that you want the transaction to be created from.
-   * <p>
-   * If left blank the 'default' server is used.
-   * </p>
-   */
-  String serverName() default "";
-
-  // int timeout() default 0;
-
-  /**
-   * The Throwable's that will explicitly cause a rollback to occur.
-   */
-  Class<? extends Throwable>[] rollbackFor() default {};
-
-  /**
-   * The Throwable's that will explicitly NOT cause a rollback to occur.
-   */
-  Class<? extends Throwable>[] noRollbackFor() default {};
-
-}

src/main/java/io/ebean/annotation/package-info.java

@@ -1,4 +0,0 @@
-/**
- * Transactional annotations.
- */
-package io.ebean.annotation;

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

@@ -3,6 +3,7 @@ package io.ebean.bean;
 import io.ebean.Ebean;
 import io.ebean.ValuePair;
 
+import java.util.Arrays;
 import javax.persistence.EntityNotFoundException;
 import javax.persistence.PersistenceException;
 import java.beans.PropertyChangeEvent;
@@ -1026,7 +1027,7 @@ public final class EntityBeanIntercept implements Serializable {
 
     if (state == STATE_NEW) {
       setLoadedProperty(propertyIndex);
-    } else if (oldValue != newValue) {
+    } else if (Double.compare(oldValue, newValue) != 0) {
       setChangedPropertyValue(propertyIndex, intercept, oldValue);
     } else {
       return null;
@@ -1041,7 +1042,7 @@ public final class EntityBeanIntercept implements Serializable {
 
     if (state == STATE_NEW) {
       setLoadedProperty(propertyIndex);
-    } else if (oldValue != newValue) {
+    } else if (Float.compare(oldValue, newValue) != 0) {
       setChangedPropertyValue(propertyIndex, intercept, oldValue);
     } else {
       return null;
@@ -1101,7 +1102,7 @@ public final class EntityBeanIntercept implements Serializable {
 
     if (state == STATE_NEW) {
       setLoadedProperty(propertyIndex);
-    } else if (!areEqualChars(oldValue, newValue)) {
+    } else if (!Arrays.equals(oldValue, newValue)) {
       setChangedPropertyValue(propertyIndex, intercept, oldValue);
     } else {
       return null;
@@ -1116,53 +1117,11 @@ public final class EntityBeanIntercept implements Serializable {
 
     if (state == STATE_NEW) {
       setLoadedProperty(propertyIndex);
-    } else if (!areEqualBytes(oldValue, newValue)) {
+    } else if (!Arrays.equals(oldValue, newValue)) {
       setChangedPropertyValue(propertyIndex, intercept, oldValue);
     } else {
       return null;
     }
     return (pcs == null) ? null : new PropertyChangeEvent(owner, getProperty(propertyIndex), oldValue, newValue);
   }
-
-  private static boolean areEqualBytes(byte[] b1, byte[] b2) {
-    if (b1 == null) {
-      return (b2 == null);
-
-    } else if (b2 == null) {
-      return false;
-
-    } else if (b1 == b2) {
-      return true;
-
-    } else if (b1.length != b2.length) {
-      return false;
-    }
-    for (int i = 0; i < b1.length; i++) {
-      if (b1[i] != b2[i]) {
-        return false;
-      }
-    }
-    return true;
-  }
-
-  private static boolean areEqualChars(char[] b1, char[] b2) {
-    if (b1 == null) {
-      return (b2 == null);
-
-    } else if (b2 == null) {
-      return false;
-
-    } else if (b1 == b2) {
-      return true;
-
-    } else if (b1.length != b2.length) {
-      return false;
-    }
-    for (int i = 0; i < b1.length; i++) {
-      if (b1[i] != b2[i]) {
-        return false;
-      }
-    }
-    return true;
-  }
 }

src/main/java/io/ebean/cache/ServerCacheFactory.java

@@ -1,5 +1,7 @@
 package io.ebean.cache;
 
+import io.ebean.config.CurrentTenantProvider;
+
 /**
  * Defines method for constructing caches for beans and queries.
  */
@@ -8,6 +10,6 @@ public interface ServerCacheFactory {
   /**
    * Create the cache for the given type with options.
    */
-  ServerCache createCache(ServerCacheType type, String cacheKey, ServerCacheOptions cacheOptions);
+  ServerCache createCache(ServerCacheType type, String cacheKey, CurrentTenantProvider tenantProvider, ServerCacheOptions cacheOptions);
 
 }

src/main/java/io/ebean/cache/TenantAwareKey.java

@@ -0,0 +1,77 @@
+package io.ebean.cache;
+
+import io.ebean.config.CurrentTenantProvider;
+
+import java.io.Serializable;
+import java.util.Objects;
+
+/**
+ * Tenant aware handling for caching.
+ */
+public class TenantAwareKey {
+
+  private final CurrentTenantProvider tenantProvider;
+
+  /**
+   * Construct with a tenant provider than can be null.
+   */
+  public TenantAwareKey(CurrentTenantProvider tenantProvider) {
+    this.tenantProvider = tenantProvider;
+  }
+
+  /**
+   * Return a tenant aware key.
+   */
+  public Object key(Object key) {
+    if (tenantProvider != null) {
+      return new CacheKey(key, tenantProvider.currentId());
+    } else {
+      return key;
+    }
+  }
+
+  /**
+   * We use a combined key, if this serverCache is per tenant.
+   */
+  public static final class CacheKey implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    final Object key;
+    final Object tenantId;
+
+    /**
+     * Create with optional tenantId.
+     */
+    public CacheKey(Object key, Object tenantId) {
+      this.key = key;
+      this.tenantId = tenantId;
+    }
+
+    @Override
+    public int hashCode() {
+      int result = key.hashCode();
+      result = 92821 * result + Objects.hashCode(tenantId);
+      return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+      if (obj instanceof CacheKey) {
+        CacheKey that = (CacheKey) obj;
+        return Objects.equals(that.key, this.key)
+          && Objects.equals(that.tenantId, this.tenantId);
+      }
+      return false;
+    }
+
+    @Override
+    public String toString() {
+      StringBuilder sb = new StringBuilder(key.toString());
+      if (tenantId != null) {
+        sb.append(":").append(tenantId);
+      }
+      return sb.toString();
+    }
+  }
+}

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

@@ -47,8 +47,7 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
   protected ModifyHolder<E> modifyHolder;
 
   protected ModifyListenMode modifyListenMode;
-  protected boolean modifyAddListening;
-  protected boolean modifyRemoveListening;
+
   protected boolean modifyListening;
 
   /**
@@ -148,9 +147,7 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
   public void setModifyListening(ModifyListenMode mode) {
 
     this.modifyListenMode = mode;
-    this.modifyAddListening = ModifyListenMode.ALL.equals(mode);
-    this.modifyRemoveListening = modifyAddListening || ModifyListenMode.REMOVALS.equals(mode);
-    this.modifyListening = modifyRemoveListening || modifyAddListening;
+    this.modifyListening = mode != null && ModifyListenMode.NONE != mode;
     if (modifyListening) {
       // lose any existing modifications
       modifyHolder = null;
@@ -173,14 +170,14 @@ abstract class AbstractBeanCollection<E> implements BeanCollection<E> {
 
   @Override
   public void modifyAddition(E bean) {
-    if (modifyAddListening) {
+    if (modifyListening) {
       getModifyHolder().modifyAddition(bean);
     }
   }
 
   @Override
   public void modifyRemoval(Object bean) {
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       getModifyHolder().modifyRemoval(bean);
     }
   }

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

@@ -232,7 +232,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public void add(int index, E element) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       modifyAddition(element);
     }
     list.add(index, element);
@@ -247,7 +247,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean add(E o) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       if (list.add(o)) {
         modifyAddition(o);
         return true;
@@ -262,7 +262,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean addAll(Collection<? extends E> c) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       // all elements in c are added (no contains checking)
       getModifyHolder().modifyAdditionAll(c);
     }
@@ -273,7 +273,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean addAll(int index, Collection<? extends E> c) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       // all elements in c are added (no contains checking)
       getModifyHolder().modifyAdditionAll(c);
     }
@@ -286,7 +286,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
     // TODO: when clear() and not initialised could be more clever
     // and fetch just the Id's
     initClear();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       for (E aList : list) {
         getModifyHolder().modifyRemoval(aList);
       }
@@ -380,7 +380,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public E remove(int index) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       E o = list.remove(index);
       modifyRemoval(o);
       return o;
@@ -392,7 +392,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean remove(Object o) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       boolean isRemove = list.remove(o);
       if (isRemove) {
         modifyRemoval(o);
@@ -406,7 +406,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean removeAll(Collection<?> beans) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       boolean changed = false;
       for (Object bean : beans) {
         if (list.remove(bean)) {
@@ -424,7 +424,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public boolean retainAll(Collection<?> retainBeans) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       boolean changed = false;
       Iterator<E> it = list.iterator();
       while (it.hasNext()) {

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

@@ -211,7 +211,7 @@ public final class BeanMap<K, E> extends AbstractBeanCollection<E> implements Ma
   public void clear() {
     checkReadOnly();
     initClear();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       // add all beans to the removal list
       for (E bean : map.values()) {
         modifyRemoval(bean);
@@ -313,7 +313,7 @@ public final class BeanMap<K, E> extends AbstractBeanCollection<E> implements Ma
   public E remove(Object key) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       E o = map.remove(key);
       modifyRemoval(o);
       return o;

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

@@ -210,7 +210,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public boolean add(E o) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       if (set.add(o)) {
         modifyAddition(o);
         return true;
@@ -225,7 +225,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public boolean addAll(Collection<? extends E> addCollection) {
     checkReadOnly();
     init();
-    if (modifyAddListening) {
+    if (modifyListening) {
       boolean changed = false;
       for (E bean : addCollection) {
         if (set.add(bean)) {
@@ -243,7 +243,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public void clear() {
     checkReadOnly();
     initClear();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       for (E bean : set) {
         modifyRemoval(bean);
       }
@@ -285,7 +285,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public boolean remove(Object o) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       if (set.remove(o)) {
         modifyRemoval(o);
         return true;
@@ -299,7 +299,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public boolean removeAll(Collection<?> beans) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       boolean changed = false;
       for (Object bean : beans) {
         if (set.remove(bean)) {
@@ -316,7 +316,7 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   public boolean retainAll(Collection<?> beans) {
     checkReadOnly();
     init();
-    if (modifyRemoveListening) {
+    if (modifyListening) {
       boolean changed = false;
       Iterator<?> it = set.iterator();
       while (it.hasNext()) {

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

@@ -44,21 +44,29 @@ class ModifyHolder<E> implements Serializable {
     }
   }
 
+  private boolean undoDeletion(E bean) {
+    return (bean != null) && modifyDeletions.remove(bean);
+  }
+
   void modifyAddition(E bean) {
     if (bean != null) {
       // If it is to delete then just remove the deletion
-      if (!modifyDeletions.remove(bean)) {
+      if (!undoDeletion(bean)) {
         // Insert
         modifyAdditions.add(bean);
       }
     }
   }
 
+  private boolean undoAddition(Object bean) {
+    return (bean != null) && modifyAdditions.remove(bean);
+  }
+
   @SuppressWarnings("unchecked")
   void modifyRemoval(Object bean) {
     if (bean != null) {
       // If it is to be added then just remove the addition
-      if (!modifyAdditions.remove(bean)) {
+      if (!undoAddition(bean)) {
         modifyDeletions.add((E) bean);
       }
     }

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

@@ -1,11 +1,13 @@
 package io.ebean.config;
 
 import io.ebean.config.dbplatform.DatabasePlatform;
+import io.ebeaninternal.server.deploy.parse.AnnotationBase;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import javax.persistence.DiscriminatorValue;
 import javax.persistence.Inheritance;
 import javax.persistence.Table;
-import java.lang.annotation.Annotation;
 
 /**
  * Provides some base implementation for NamingConventions.
@@ -14,16 +16,15 @@ import java.lang.annotation.Annotation;
  */
 public abstract class AbstractNamingConvention implements NamingConvention {
 
+  private static final Pattern TABLE_REPLACE = Pattern.compile("{table}", Pattern.LITERAL);
+
+  private static final Pattern COLUMN_REPLACE = Pattern.compile("{column}", Pattern.LITERAL);
+
   /**
    * The Constant DEFAULT_SEQ_FORMAT.
    */
   public static final String DEFAULT_SEQ_FORMAT = "{table}_seq";
 
-  /**
-   * Sequence Format that includes the Primary Key column
-   */
-  public static final String TABLE_PKCOLUMN_SEQ_FORMAT = "{table}_{column}_seq";
-
   /**
    * The catalog.
    */
@@ -83,11 +84,11 @@ public abstract class AbstractNamingConvention implements NamingConvention {
 
   @Override
   public String getSequenceName(String tableName, String pkColumn) {
-    String s = sequenceFormat.replace("{table}", tableName);
+    String s = TABLE_REPLACE.matcher(sequenceFormat).replaceAll(Matcher.quoteReplacement(tableName));
     if (pkColumn == null) {
       pkColumn = "";
     }
-    return s.replace("{column}", pkColumn);
+    return COLUMN_REPLACE.matcher(s).replaceAll(Matcher.quoteReplacement(pkColumn));
   }
 
   /**
@@ -185,45 +186,43 @@ public abstract class AbstractNamingConvention implements NamingConvention {
    */
   @Override
   public TableName getTableName(Class<?> beanClass) {
+    while (true) {
 
-    TableName tableName = getTableNameFromAnnotation(beanClass);
-    if (tableName == null) {
-      Class<?> supCls = beanClass.getSuperclass();
-      if (hasInheritance(supCls)) {
-        // get the table as per inherited class in case there
-        // is not a table annotation in the inheritance hierarchy
-        return getTableName(supCls);
+      TableName tableName = getTableNameFromAnnotation(beanClass);
+      if (tableName == null) {
+        Class<?> supCls = beanClass.getSuperclass();
+        if (hasInheritance(supCls)) {
+          // get the table as per inherited class in case there
+          // is not a table annotation in the inheritance hierarchy
+          beanClass = supCls;
+          continue;
+        }
+
+        tableName = getTableNameByConvention(beanClass);
       }
 
-      tableName = getTableNameByConvention(beanClass);
+      // Use naming convention for catalog or schema,
+      // if not set in the annotation.
+      String catalog = tableName.getCatalog();
+      if (isEmpty(catalog)) {
+        catalog = getCatalog();
+      }
+      String schema = tableName.getSchema();
+      if (isEmpty(schema)) {
+        schema = getSchema();
+      }
+      return new TableName(catalog, schema, tableName.getName());
     }
-
-    // Use naming convention for catalog or schema,
-    // if not set in the annotation.
-    String catalog = tableName.getCatalog();
-    if (isEmpty(catalog)) {
-      catalog = getCatalog();
-    }
-    String schema = tableName.getSchema();
-    if (isEmpty(schema)) {
-      schema = getSchema();
-    }
-    return new TableName(catalog, schema, tableName.getName());
   }
 
   /**
    * Return true if this class is part of entity inheritance.
    */
   protected boolean hasInheritance(Class<?> supCls) {
-    return hasAnnotation(supCls, Inheritance.class) || hasAnnotation(supCls, DiscriminatorValue.class);
+    return AnnotationBase.findAnnotationRecursive(supCls, Inheritance.class) != null 
+        || AnnotationBase.findAnnotation(supCls, DiscriminatorValue.class) != null;
   }
 
-  /**
-   * Return true if the class has the given annotation.
-   */
-  protected boolean hasAnnotation(Class<?> supCls, Class<? extends Annotation> annotation) {
-    return supCls.getAnnotation(annotation) != null;
-  }
 
   @Override
   public TableName getM2MJoinTableName(TableName lhsTable, TableName rhsTable) {
@@ -254,7 +253,7 @@ public abstract class AbstractNamingConvention implements NamingConvention {
    */
   protected TableName getTableNameFromAnnotation(Class<?> beanClass) {
 
-    final Table t = findTableAnnotation(beanClass);
+    final Table t = AnnotationBase.findAnnotationRecursive(beanClass, Table.class);
 
     // Take the annotation if defined
     if (t != null && !isEmpty(t.name())) {
@@ -267,20 +266,6 @@ public abstract class AbstractNamingConvention implements NamingConvention {
     return null;
   }
 
-  /**
-   * Search recursively for an @Table in the class hierarchy.
-   */
-  protected Table findTableAnnotation(Class<?> cls) {
-    if (cls.equals(Object.class)) {
-      return null;
-    }
-    Table table = cls.getAnnotation(Table.class);
-    if (table != null) {
-      return table;
-    }
-    return findTableAnnotation(cls.getSuperclass());
-  }
-
   /**
    * Replace back ticks (if they are used) with database platform specific
    * quoted identifiers.

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

@@ -118,7 +118,7 @@ public class ClassLoadConfig {
   /**
    * Wraps the preferred, caller and context class loaders.
    */
-  protected class ClassLoaderContext {
+  protected static class ClassLoaderContext {
 
     /**
      * Optional - if set only use this classLoader (no fallback).

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

@@ -1,12 +1,13 @@
 package io.ebean.config;
 
 import io.ebean.Platform;
-import io.ebean.dbmigration.MigrationConfig;
-import io.ebean.dbmigration.MigrationRunner;
+import io.ebean.migration.MigrationConfig;
+import io.ebean.migration.MigrationRunner;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.util.Map;
+import java.util.Properties;
 
 /**
  * Configuration for the DB migration processing.
@@ -443,7 +444,7 @@ public class DbMigrationConfig {
   /**
    * Create the MigrationRunner to run migrations if necessary.
    */
-  public MigrationRunner createRunner(ClassLoader classLoader) {
+  public MigrationRunner createRunner(ClassLoader classLoader, Properties properties) {
 
     MigrationConfig runnerConfig = new MigrationConfig();
     runnerConfig.setMetaTable(metaTable);
@@ -454,6 +455,9 @@ public class DbMigrationConfig {
     runnerConfig.setDbUsername(getDbUsername());
     runnerConfig.setDbPassword(getDbPassword());
     runnerConfig.setClassLoader(classLoader);
+    if (properties != null) {
+      runnerConfig.load(properties);
+    }
     return new MigrationRunner(runnerConfig);
   }
 }

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

@@ -31,7 +31,7 @@ public class MatchingNamingConvention extends AbstractNamingConvention {
 
   @Override
   public String getColumnFromProperty(Class<?> beanClass, String propertyName) {
-    return propertyName;
+    return quoteIdentifiers(propertyName);
   }
 
   @Override
@@ -47,8 +47,11 @@ public class MatchingNamingConvention extends AbstractNamingConvention {
 
   @Override
   public String getForeignKey(String prefix, String fkProperty) {
+    prefix = databasePlatform.unQuote(prefix);
+    fkProperty = databasePlatform.unQuote(fkProperty);
     // add fkProperty as init caps
-    return prefix + fkProperty.substring(0, 1).toUpperCase() + fkProperty.substring(1);
+    String fullName = prefix + fkProperty.substring(0, 1).toUpperCase() + fkProperty.substring(1);
+    return quoteIdentifiers(fullName);
   }
 
 }

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

@@ -91,7 +91,7 @@ final class PropertyExpression {
       // in which properties are being set/loaded. You can use
       // GlobalProperties.evaluateExpressions() to get any unresolved
       // expressions to be evaluated
-      logger.debug("Unable to evaluate expression [" + exp + "]");
+      logger.debug("Unable to evaluate expression [{}]", exp);
       return null;
     }
   }

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

@@ -1,5 +1,7 @@
 package io.ebean.config;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -18,6 +20,8 @@ final class PropertyMapLoader {
 
   private static final Logger logger = LoggerFactory.getLogger(PropertyMapLoader.class);
 
+  private static final Pattern OTHER_PROPS_REPLACE = Pattern.compile("\\", Pattern.LITERAL);
+
   /**
    * Load the <code>test-ebean.properties</code>.
    */
@@ -109,10 +113,10 @@ final class PropertyMapLoader {
       otherProps = p.remove("load.properties.override");
     }
     if (otherProps != null) {
-      otherProps = otherProps.replace("\\", "/");
+      otherProps = OTHER_PROPS_REPLACE.matcher(otherProps).replaceAll(Matcher.quoteReplacement("/"));
       InputStream is = findInputStream(otherProps);
       if (is != null) {
-        logger.debug("loading properties from " + otherProps);
+        logger.debug("loading properties from {}", otherProps);
         load(p, is);
       } else {
         logger.error("load.properties " + otherProps + " not found.");
@@ -135,12 +139,12 @@ final class PropertyMapLoader {
       File f = new File(fileName);
 
       if (f.exists()) {
-        logger.debug(fileName + " found in file system");
+        logger.debug("{} found in file system", fileName);
         return new FileInputStream(f);
       } else {
         InputStream in = findInClassPath(fileName);
         if (in != null) {
-          logger.debug(fileName + " found in classpath");
+          logger.debug("{} found in classpath", fileName);
         }
         return in;
       }

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

@@ -1,27 +1,24 @@
 package io.ebean.config;
 
 /**
+ * Matches the functionality of javax.persistence.AttributeConverter
+ * <p>
+ * In general AttributeConverter should be used in preference to this
+ * ScalarTypeConverter as it is JPA standard and offers the same functionality.
+ * </p>
+ * <p>
+ * For Ebean we will look to deprecate this interface in preference to AttributeConverter.
+ * </p>
+ * <p>
  * Used to convert between a value object and a known scalar type. The value
  * object is the logical type used in your application and the scalar type is
  * the value used to persist than to the DB.
+ * </p>
  * <p>
  * The Value object should be immutable and scalar (aka not compound) and
  * converts to and from a known scalar type which Ebean will use to persist the
  * value.
  * </p>
- * <p>
- * This is an easier alternative to implementing the
- * io.ebean.server.type.ScalarType interface.
- * </p>
- * <p>
- * Note that Ebean will automatically try to detect Immutable Scalar Value
- * Objects and automatically support them via reflection. This however would not
- * be appropriate when the logical type is different from the type you wish to
- * use for persistence - for example, if the logical type was long and you
- * wanted to use java.sql.Timestamp for persistence. In this case you would want
- * to implement this interface rather than let Ebean automatically support that
- * type via reflection.
- * </p>
  *
  * @param <B> The value object type.
  * @param <S> The scalar object type that is used to persist the value object.

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

@@ -12,7 +12,8 @@ import io.ebean.cache.ServerCachePlugin;
 import io.ebean.config.dbplatform.DatabasePlatform;
 import io.ebean.config.dbplatform.DbEncrypt;
 import io.ebean.config.dbplatform.DbType;
-import io.ebean.dbmigration.MigrationRunner;
+import io.ebean.dbmigration.DbOffline;
+import io.ebean.migration.MigrationRunner;
 import io.ebean.event.BeanFindController;
 import io.ebean.event.BeanPersistController;
 import io.ebean.event.BeanPersistListener;
@@ -27,6 +28,8 @@ import io.ebean.event.changelog.ChangeLogRegister;
 import io.ebean.event.readaudit.ReadAuditLogger;
 import io.ebean.event.readaudit.ReadAuditPrepare;
 import io.ebean.meta.MetaInfoManager;
+import io.ebean.util.StringHelper;
+
 import org.avaje.datasource.DataSourceConfig;
 
 import javax.sql.DataSource;
@@ -80,12 +83,6 @@ public class ServerConfig {
    */
   private String name = "db";
 
-  /**
-   * When false (default) H2 automatically uses DDL generate and run
-   * (i.e. assumes we are running tests using in memory h2).
-   */
-  private boolean h2ProductionMode;
-
   /**
    * Typically configuration type objects that are passed by this ServerConfig
    * to plugins. For example - IgniteConfiguration passed to Ignite plugin.
@@ -129,6 +126,8 @@ public class ServerConfig {
 
   private TenantSchemaProvider tenantSchemaProvider;
 
+  private TenantCatalogProvider tenantCatalogProvider;
+
   /**
    * List of interesting classes such as entities, embedded, ScalarTypes,
    * Listeners, Finders, Controllers etc.
@@ -317,6 +316,8 @@ public class ServerConfig {
    */
   private String databaseBooleanFalse;
 
+  private boolean allQuotedIdentifiers;
+
   /**
    * The naming convention.
    */
@@ -525,27 +526,6 @@ public class ServerConfig {
     this.name = name;
   }
 
-  /**
-   * Return true if H2 should be used in production mode.
-   * <p>
-   * Otherwise it is assumed we are using H2 for testing and DDL generate and run is turned on.
-   * </p>
-   */
-  public boolean isH2ProductionMode() {
-    return h2ProductionMode;
-  }
-
-  /**
-   * Set to true for H2 to be used in production mode.
-   * <p>
-   * Do this when we want to use H2 and not have the DDL generation and run automatically turned on.
-   * Otherwise it is assumed we are using H2 for testing purposes.
-   * </p>
-   */
-  public void setH2ProductionMode(boolean h2ProductionMode) {
-    this.h2ProductionMode = h2ProductionMode;
-  }
-
   /**
    * Return the container / clustering configuration.
    * <p/>
@@ -696,6 +676,20 @@ public class ServerConfig {
     this.tenantSchemaProvider = tenantSchemaProvider;
   }
 
+  /**
+   * Return the tenancy catalog provider.
+   */
+  public TenantCatalogProvider getTenantCatalogProvider() {
+    return tenantCatalogProvider;
+  }
+
+  /**
+   * Set the tenancy catalog provider.
+   */
+  public void setTenantCatalogProvider(TenantCatalogProvider tenantCatalogProvider) {
+    this.tenantCatalogProvider = tenantCatalogProvider;
+  }
+
   /**
    * Return the PersistBatch mode to use by default at the transaction level.
    * <p>
@@ -1285,6 +1279,24 @@ public class ServerConfig {
     this.namingConvention = namingConvention;
   }
 
+  /**
+   * Return true if all DB column and table names should use quoted identifiers.
+   */
+  public boolean isAllQuotedIdentifiers() {
+    return allQuotedIdentifiers;
+  }
+
+  /**
+   * Set to true if all DB column and table names should use quoted identifiers.
+   */
+  public void setAllQuotedIdentifiers(boolean allQuotedIdentifiers) {
+    this.allQuotedIdentifiers = allQuotedIdentifiers;
+    if (allQuotedIdentifiers && namingConvention instanceof UnderscoreNamingConvention) {
+      // we need to use matching naming convention
+      this.namingConvention = new MatchingNamingConvention();
+    }
+  }
+
   /**
    * Return true if this EbeanServer is a Document store only instance (has no JDBC DB).
    */
@@ -1551,11 +1563,6 @@ public class ServerConfig {
    */
   public void setDatabasePlatform(DatabasePlatform databasePlatform) {
     this.databasePlatform = databasePlatform;
-    if (!h2ProductionMode && databasePlatform != null && databasePlatform.isPlatform(Platform.H2)) {
-      // we are using H2 to run tests so turn on DDL generation and run
-      this.ddlGenerate = true;
-      this.ddlRun = true;
-    }
   }
 
   /**
@@ -1625,6 +1632,16 @@ public class ServerConfig {
     this.encryptor = encryptor;
   }
 
+  /**
+   * Return true if the instance is coming up in offline mode.
+   * <p>
+   * Offline mode is mostly used when generating DB migration.
+   * </p>
+   */
+  public boolean isOfflineMode() {
+    return dbOffline || DbOffline.isSet();
+  }
+
   /**
    * Return true if the EbeanServer instance should be created in offline mode.
    */
@@ -2488,6 +2505,11 @@ public class ServerConfig {
 
     migrationConfig.loadSettings(p, name);
 
+    boolean quotedIdentifiers = p.getBoolean("allQuotedIdentifiers", allQuotedIdentifiers);
+    if (quotedIdentifiers != allQuotedIdentifiers) {
+      // potentially also set to use matching naming convention
+      setAllQuotedIdentifiers(quotedIdentifiers);
+    }
     namingConvention = createNamingConvention(p, namingConvention);
     if (namingConvention != null) {
       namingConvention.loadFromProperties(p);
@@ -2594,7 +2616,6 @@ public class ServerConfig {
       jsonDateTime = JsonConfig.DateTime.MILLIS;
     }
 
-    h2ProductionMode = p.getBoolean("h2ProductionMode", h2ProductionMode);
     ddlGenerate = p.getBoolean("ddl.generate", ddlGenerate);
     ddlRun = p.getBoolean("ddl.run", ddlRun);
     ddlCreateOnly = p.getBoolean("ddl.createOnly", ddlCreateOnly);
@@ -2625,10 +2646,9 @@ public class ServerConfig {
 
     List<Class<?>> classes = new ArrayList<>();
 
-    String[] split = classNames.split("[ ,;]");
-    for (String aSplit : split) {
-      String cn = aSplit.trim();
-      if (!cn.isEmpty() && !"class".equalsIgnoreCase(cn)) {
+    String[] split = StringHelper.splitNames(classNames);
+    for (String cn : split) {
+      if (!"class".equalsIgnoreCase(cn)) {
         try {
           classes.add(Class.forName(cn));
         } catch (ClassNotFoundException e) {
@@ -2646,9 +2666,9 @@ public class ServerConfig {
 
     if (searchPackages != null) {
 
-      String[] entries = searchPackages.split("[ ,;]");
+      String[] entries = StringHelper.splitNames(searchPackages);
       for (String entry : entries) {
-        hitList.add(entry.trim());
+        hitList.add(entry);
       }
     }
     return hitList;
@@ -2739,7 +2759,7 @@ public class ServerConfig {
    */
   public DataSource runDbMigration(DataSource dataSource) {
     if (migrationConfig.isRunMigration()) {
-      MigrationRunner runner = migrationConfig.createRunner(getClassLoadConfig().getClassLoader());
+      MigrationRunner runner = migrationConfig.createRunner(getClassLoadConfig().getClassLoader(), properties);
       runner.run(dataSource);
     }
     return dataSource;

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

@@ -0,0 +1,16 @@
+package io.ebean.config;
+
+/**
+ * For multi-tenancy via DB CATALOG supply the catalog given the tenantId.
+ */
+@FunctionalInterface
+public interface TenantCatalogProvider {
+
+  /**
+   * Return the DB catalog for the given tenantId.
+   *
+   * @param tenantId The current tenant id.
+   * @return The DB catalog to use for the given tenant
+   */
+  String catalog(Object tenantId);
+}

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

@@ -20,6 +20,11 @@ public enum TenantMode {
    */
   SCHEMA(true),
 
+  /**
+   * Each Tenant has their own Database but with in connection pool
+   */
+  CATALOG(true),
+
   /**
    * Tenants share tables but have a discriminator/partition column that partitions the data.
    */

src/main/java/io/ebean/config/dbplatform/DatabasePlatform.java

@@ -64,6 +64,11 @@ public class DatabasePlatform {
    */
   protected String closeQuote = "\"";
 
+  /**
+   * When set to true all db column names and table names use quoted identifiers.
+   */
+  protected boolean allQuotedIdentifiers;
+
   /**
    * For limit/offset, row_number etc limiting of SQL queries.
    */
@@ -175,6 +180,8 @@ public class DatabasePlatform {
 
   protected SqlExceptionTranslator exceptionTranslator = new SqlCodeTranslator();
 
+  protected char[] specialLikeCharacters = { '%', '_' };
+
   /**
    * Instantiates a new database platform.
    */
@@ -191,7 +198,8 @@ public class DatabasePlatform {
   /**
    * Configure UUID Storage etc based on ServerConfig settings.
    */
-  public void configure(DbTypeConfig config) {
+  public void configure(DbTypeConfig config, boolean allQuotedIdentifiers) {
+    this.allQuotedIdentifiers = allQuotedIdentifiers;
     addGeoTypes(config.getGeometrySRID());
     configureIdType(config.getIdType());
     dbTypeMap.config(nativeUuidType, config.getDbUuid());
@@ -279,6 +287,9 @@ public class DatabasePlatform {
    * Create and return a DDL handler for generating DDL scripts.
    */
   public DdlHandler createDdlHandler(ServerConfig serverConfig) {
+    if (platformDdl == null) {
+      throw new IllegalStateException("Platform " + getName() + " has no DDL Handler");
+    }
     return platformDdl.createDdlHandler(serverConfig);
   }
 
@@ -533,24 +544,33 @@ public class DatabasePlatform {
    * naming rules.
    * </p>
    *
-   * @param dbName the db name
-   * @return the string
+   * @param dbName the db table or column name
+   * @return the db table or column name with potentially platform specific quoted identifiers
    */
   public String convertQuotedIdentifiers(String dbName) {
     // Ignore null values e.g. schema name or catalog
     if (dbName != null && !dbName.isEmpty()) {
       if (dbName.charAt(0) == BACK_TICK) {
         if (dbName.charAt(dbName.length() - 1) == BACK_TICK) {
-
-          String quotedName = getOpenQuote();
-          quotedName += dbName.substring(1, dbName.length() - 1);
-          quotedName += getCloseQuote();
-
-          return quotedName;
-
+          return openQuote + dbName.substring(1, dbName.length() - 1) + closeQuote;
         } else {
           logger.error("Missing backquote on [" + dbName + "]");
         }
+      } else if (allQuotedIdentifiers) {
+        return openQuote + dbName + closeQuote;
+      }
+    }
+    return dbName;
+  }
+
+  /**
+   * Remove quoted identifier quotes from the table or column name if present.
+   */
+  public String unQuote(String dbName) {
+    if (dbName != null && !dbName.isEmpty()) {
+      if (dbName.startsWith(openQuote)) {
+        // trim off the open and close quotes
+        return dbName.substring(1, dbName.length()-1);
       }
     }
     return dbName;
@@ -617,4 +637,37 @@ public class DatabasePlatform {
       logger.error("Error closing resultSet", e);
     }
   }
+
+  /**
+   * Escapes the like string for this DB-Platform
+   */
+  public String escapeLikeString(String value) {
+    StringBuilder sb = null;
+    for (int i = 0; i < value.length(); i++) {
+      char ch = value.charAt(i);
+      boolean escaped = false;
+      for (char escapeChar: specialLikeCharacters) {
+        if (ch == escapeChar) {
+          if (sb == null) {
+            sb = new StringBuilder(value.substring(0, i));
+          }
+          escapeLikeCharacter(escapeChar, sb);
+          escaped = true;
+          break;
+        }
+      }
+      if (!escaped && sb != null) {
+        sb.append(ch);
+      }
+    }
+    if (sb == null) {
+      return value;
+    } else {
+      return sb.toString();
+    }
+  }
+
+  protected void escapeLikeCharacter(char ch, StringBuilder sb) {
+    sb.append('\\').append(ch);
+  }
 }

src/main/java/io/ebean/config/dbplatform/DbDefaultValue.java

@@ -1,8 +1,13 @@
 package io.ebean.config.dbplatform;
 
+import java.sql.Types;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
+import javax.xml.bind.DatatypeConverter;
+
+import io.ebean.annotation.DbDefault;
+
 /**
  * DB Column default values mapping to database platform specific literals.
  */
@@ -22,6 +27,13 @@ public class DbDefaultValue {
    * The key for the NOW / current timestamp.
    */
   public static final String NOW = "now";
+  
+  /**
+   * The 'null' literal.
+   */
+  public static final String NULL = "null";
+  
+
 
   protected Map<String, String> map = new LinkedHashMap<>();
 
@@ -63,8 +75,128 @@ public class DbDefaultValue {
     if (dbDefaultLiteral == null) {
       return null;
     }
+    if (dbDefaultLiteral.startsWith("$RAW:")) {
+      return dbDefaultLiteral.substring(5);
+    }
     String val = map.get(dbDefaultLiteral);
     return val != null ? val : dbDefaultLiteral;
   }
 
+  
+  /**
+   * This method checks & convert the {@link DbDefault#value()} to a valid SQL literal.
+   * 
+   * This is mainly to quote string literals and verify integer/dates for correctness.
+   * <p>
+   * Note: There are some special cases:
+   * </p>
+   * <ul>
+   *    <li>Normal Quoting: <code>@DbDefault("User's default")</code> on a String propery
+   *        returns: <code>default 'User''s default'</code><br/>
+   *        (the same on an integer property will throw a NumberFormatException)</li>
+   *    <li>Special case null: <code>@DbDefault("null")</code> will return this: <code>default null</code><br/>
+   *        If you need really the String "null", you have to specify <code>@DbDefault("'null'")</code>
+   *        which gives you the <code>default 'null'</code> statement.</li>
+   *    <li>Any statement, that begins and ends with single quote will not be checked or get quoted again.</li>
+   *    <li>A statement that begins with "$RAW:", e.g <code>@DbDefault("$RAW:N'SANDNES'")</code> will lead to 
+   *        a <code>default N'SANDNES'</code> in DDL. Note that this is platform specific!</li>
+   * </ul>
+   */
+  public static String toSqlLiteral(String defaultValue, Class<?> propertyType, int sqlType) {
+    if (propertyType == null
+        || defaultValue == null 
+        || NULL.equals(defaultValue)
+        || (defaultValue.startsWith("'") && defaultValue.endsWith("'"))
+        || (defaultValue.startsWith("$RAW:"))) {  
+      return defaultValue;
+    }
+
+    if (Boolean.class.isAssignableFrom(propertyType) || Boolean.TYPE.isAssignableFrom(propertyType)) {
+      return toBooleanLiteral(defaultValue);
+    }
+    
+    if (Number.class.isAssignableFrom(propertyType) 
+        || Byte.TYPE.equals(propertyType)
+        || Short.TYPE.equals(propertyType)
+        || Integer.TYPE.equals(propertyType)
+        || Long.TYPE.equals(propertyType)
+        || Float.TYPE.equals(propertyType)
+        || Double.TYPE.equals(propertyType)
+        || (propertyType.isEnum() && sqlType == Types.INTEGER)) {
+      Double.valueOf(defaultValue); // verify if it is a number
+      return defaultValue;
+    }
+   
+    // check if it is a date/time - in all other cases return quoted defaultValue
+    switch (sqlType) {
+      // date
+      case Types.DATE:
+        return toDateLiteral(defaultValue);
+      // time
+      case Types.TIME:
+      case Types.TIME_WITH_TIMEZONE:
+        return toTimeLiteral(defaultValue);
+      // timestamp
+      case Types.TIMESTAMP:
+      case Types.TIMESTAMP_WITH_TIMEZONE:
+        return toDateTimeLiteral(defaultValue);
+
+      default:
+        return toTextLiteral(defaultValue); // do not check other datatypes
+    }
+  }
+
+  /**
+   * Checks if specified value is either 'true' or 'false'. The literal is translated later.
+   */
+  private static String toBooleanLiteral(String value) {
+    if (DbDefaultValue.FALSE.equals(value) || DbDefaultValue.TRUE.equals(value)) {
+      return value;
+    }
+    throw new IllegalArgumentException("'" + value + "' is not a valid value for boolean");
+  }
+  
+  /**
+   * This adds single qoutes around the <code>value</code> and doubles single quotes.
+   * "User's home" will return "'User''s home'"
+   */
+  private static String toTextLiteral(String value) {
+    StringBuilder sb = new StringBuilder(value.length()+10);
+    sb.append('\'');
+    for (int i = 0; i < value.length(); i++) {
+      char ch = value.charAt(i);
+      if (ch == '\'') {
+        sb.append("''");
+      } else {
+        sb.append(ch);
+      }
+    }
+    sb.append('\'');
+    return sb.toString();
+
+  }
+  
+  private static String toDateLiteral(String value) {
+    if (NOW.equals(value)) {
+      return value; // this will get translated later
+    }
+    DatatypeConverter.parseDate(value); // verify
+    return toTextLiteral(value);
+  }
+
+  private static String toTimeLiteral(String value) {
+    if (NOW.equals(value)) {
+      return value; // this will get translated later
+    }
+    DatatypeConverter.parseTime(value); // verify
+    return toTextLiteral(value);
+  }
+  
+  private static String toDateTimeLiteral(String value) {
+    if (NOW.equals(value)) {
+      return value; // this will get translated later
+    }
+    DatatypeConverter.parseDateTime(value); // verify
+    return toTextLiteral(value);
+  }
 }

src/main/java/io/ebean/config/dbplatform/DbIdentity.java

@@ -1,12 +1,16 @@
 package io.ebean.config.dbplatform;
 
 import io.ebean.dbmigration.migration.IdentityType;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /**
  * Defines the identity/sequence behaviour for the database.
  */
 public class DbIdentity {
 
+  private static final Pattern TABLE_REPLACE = Pattern.compile("{table}", Pattern.LITERAL);
+
   /**
    * Set if this DB supports sequences. Note some DB's support both Sequences
    * and Identity.
@@ -50,7 +54,8 @@ public class DbIdentity {
     if (selectLastInsertedIdTemplate == null) {
       return null;
     }
-    return selectLastInsertedIdTemplate.replace("{table}", table);
+
+    return TABLE_REPLACE.matcher(selectLastInsertedIdTemplate).replaceAll(Matcher.quoteReplacement(table));
   }
 
   /**

src/main/java/io/ebean/config/dbplatform/DbPlatformType.java

@@ -130,7 +130,9 @@ public class DbPlatformType implements ExtraDbTypes {
     if (canHaveLength || !strict) {
       // see if there is a precision/scale to add (or not)
       int len = deployLength != 0 ? deployLength : defaultLength;
-      if (len > 0) {
+      if (len == Integer.MAX_VALUE) {
+        sb.append("(max)"); // TODO: this is sqlserver specific
+      } else if (len > 0) {
         sb.append("(");
         sb.append(len);
         int scale = deployScale != 0 ? deployScale : defaultScale;

src/main/java/io/ebean/config/dbplatform/DbPlatformTypeParser.java

@@ -30,7 +30,8 @@ class DbPlatformTypeParser {
 
       } else {
         String type = columnDefinition.substring(0, openPos);
-        int scale = Integer.parseInt(columnDefinition.substring(openPos + 1, closePos));
+        String strScale = columnDefinition.substring(openPos + 1, closePos);
+        int scale = strScale.equalsIgnoreCase("max") ? Integer.MAX_VALUE : Integer.parseInt(strScale);
         return new DbPlatformType(type, scale);
       }
     } catch (RuntimeException e) {

src/main/java/io/ebean/config/dbplatform/SequenceIdGenerator.java

@@ -162,9 +162,7 @@ public abstract class SequenceIdGenerator implements PlatformIdGenerator {
     }
 
     synchronized (monitor) {
-      for (Long newId : newIds) {
-        idList.add(newId);
-      }
+      idList.addAll(newIds);
     }
   }
 

src/main/java/io/ebean/config/dbplatform/db2/DB2Platform.java

@@ -1,6 +1,7 @@
 package io.ebean.config.dbplatform.db2;
 
 import io.ebean.BackgroundExecutor;
+import io.ebean.PersistBatch;
 import io.ebean.Platform;
 import io.ebean.config.dbplatform.DatabasePlatform;
 import io.ebean.config.dbplatform.DbPlatformType;
@@ -30,15 +31,21 @@ public class DB2Platform extends DatabasePlatform {
 
     this.exceptionTranslator =
       new SqlErrorCodes()
-        //.addAcquireLock("")
-        .addDuplicateKey("-803")
-        .addDataIntegrity("-407","-530","-531","-532","-543","-544","-545","-603","-667")
+        .addAcquireLock("40001","57033") // key -911/-913
+        .addDuplicateKey("23505") // -803
+        // .addDataIntegrity("-407","-530","-531","-532","-543","-544","-545","-603","-667")
+        // we need SQLState, not code: https://www.ibm.com/support/knowledgecenter/en/SSEPEK_10.0.0/codes/src/tpc/db2z_n.html
+        .addDataIntegrity("23502","23503","23504","23511","23512","23511","42917","23515")
         .build();
 
     booleanDbType = Types.BOOLEAN;
+    dbTypeMap.put(DbType.TINYINT, new DbPlatformType("smallint", false));
+    dbTypeMap.put(DbType.INTEGER, new DbPlatformType("integer", false));
+    dbTypeMap.put(DbType.BIGINT, new DbPlatformType("bigint", false));
     dbTypeMap.put(DbType.REAL, new DbPlatformType("real"));
-    dbTypeMap.put(DbType.TINYINT, new DbPlatformType("smallint"));
     dbTypeMap.put(DbType.DECIMAL, new DbPlatformType("decimal", 15));
+    
+    persistBatchOnCascade = PersistBatch.NONE;
   }
 
   /**

src/main/java/io/ebean/config/dbplatform/h2/H2HistoryTrigger.java

@@ -49,7 +49,7 @@ public class H2HistoryTrigger implements Trigger {
 
     // build the insert into history table SQL
     StringBuilder insertSql = new StringBuilder(150);
-    insertSql.append("insert into ").append(tableName).append(HISTORY_SUFFIX).append(" (");
+    insertSql.append("insert into ").append(schemaName).append(".").append(tableName).append(HISTORY_SUFFIX).append(" (");
 
     int count = 0;
     while (rs.next()) {

src/main/java/io/ebean/config/dbplatform/h2/H2Platform.java

@@ -30,7 +30,7 @@ public class H2Platform extends DatabasePlatform {
 
     this.exceptionTranslator =
       new SqlErrorCodes()
-        .addAcquireLock("50200")
+        .addAcquireLock("50200","HYT00")
         .addDuplicateKey("23001","23505")
         .addDataIntegrity("22001","22003","22012","22018","22025","23000","23002","23003","23502","23503","23506","23507","23513")
         .build();
@@ -40,10 +40,6 @@ public class H2Platform extends DatabasePlatform {
     this.dbIdentity.setSupportsSequence(true);
     this.dbIdentity.setSupportsIdentity(true);
 
-    // like ? escape'' not working in the latest version H2 so just using no
-    // escape clause for now noting that backslash is an escape char for like in H2
-    this.likeClause = "like ?";
-
     dbTypeMap.put(DbType.UUID, new DbPlatformType("uuid", false));
   }
 

src/main/java/io/ebean/config/dbplatform/mysql/MySqlPlatform.java

@@ -30,7 +30,6 @@ public class MySqlPlatform extends DatabasePlatform {
     super();
     this.platform = Platform.MYSQL;
     this.useExtraTransactionOnIterateSecondaryQueries = true;
-    this.likeClause = "like ? escape''";
     this.selectCountWithAlias = true;
     this.dbEncrypt = new MySqlDbEncrypt();
     this.platformDdl = new MySqlDdl(this);
@@ -46,7 +45,7 @@ public class MySqlPlatform extends DatabasePlatform {
       new SqlErrorCodes()
         .addAcquireLock("1205")
         .addDuplicateKey("1062")
-        .addDataIntegrity("630","839","840","893","1169","1215","1216","1217","1364","1451","1452","1557")
+        .addDataIntegrity("630","839","840","893","1169","1215","1216","1217","1364","1451","1452","1557","23000")
         .build();
 
     this.openQuote = "`";

src/main/java/io/ebean/config/dbplatform/postgres/PostgresPlatform.java

@@ -28,7 +28,6 @@ public class PostgresPlatform extends DatabasePlatform {
     super();
     this.platform = Platform.POSTGRES;
     this.supportsNativeIlike = true;
-    this.likeClause = "like ? escape''";
     this.selectCountWithAlias = true;
     this.blobDbType = Types.LONGVARBINARY;
     this.clobDbType = Types.VARCHAR;

src/main/java/io/ebean/config/dbplatform/sqlserver/SqlServerPlatform.java

@@ -8,7 +8,6 @@ import io.ebean.config.dbplatform.DbType;
 import io.ebean.config.dbplatform.IdType;
 import io.ebean.config.dbplatform.SqlErrorCodes;
 import io.ebean.dbmigration.ddlgeneration.platform.SqlServerDdl;
-
 import java.sql.Types;
 
 /**
@@ -35,12 +34,14 @@ public class SqlServerPlatform extends DatabasePlatform {
     this.exceptionTranslator =
       new SqlErrorCodes()
         .addAcquireLock("1222")
-        .addDuplicateKey("2601","2627")
-        .addDataIntegrity("544","8114","8115")
+        .addDuplicateKey("2601", "2627")
+        .addDataIntegrity("544", "8114", "8115")
         .build();
 
     this.openQuote = "[";
     this.closeQuote = "]";
+    this.specialLikeCharacters = new char[]{'%', '_', '['};
+    this.likeClause = "like ? COLLATE Latin1_General_BIN";
 
     booleanDbType = Types.INTEGER;
     dbTypeMap.put(DbType.BOOLEAN, new DbPlatformType("bit default 0"));
@@ -61,6 +62,13 @@ public class SqlServerPlatform extends DatabasePlatform {
     dbTypeMap.put(DbType.TIME, new DbPlatformType("time"));
     dbTypeMap.put(DbType.TIMESTAMP, new DbPlatformType("datetime2"));
 
+    dbTypeMap.put(DbType.JSON, new DbPlatformType("nvarchar", Integer.MAX_VALUE));
+    dbTypeMap.put(DbType.JSONB, new DbPlatformType("nvarchar", Integer.MAX_VALUE));
+
   }
 
+  @Override
+  protected void escapeLikeCharacter(char ch, StringBuilder sb) {
+    sb.append('[').append(ch).append(']');
+  }
 }

src/main/java/io/ebean/dbmigration/DbMigration.java

@@ -9,10 +9,12 @@ import io.ebean.config.ServerConfig;
 import io.ebean.config.dbplatform.db2.DB2Platform;
 import io.ebean.config.dbplatform.DatabasePlatform;
 import io.ebean.config.dbplatform.h2.H2Platform;
+import io.ebean.config.dbplatform.hsqldb.HsqldbPlatform;
 import io.ebean.config.dbplatform.sqlserver.SqlServerPlatform;
 import io.ebean.config.dbplatform.mysql.MySqlPlatform;
 import io.ebean.config.dbplatform.oracle.OraclePlatform;
 import io.ebean.config.dbplatform.postgres.PostgresPlatform;
+import io.ebean.config.dbplatform.sqlanywhere.SqlAnywherePlatform;
 import io.ebean.config.dbplatform.sqlite.SQLitePlatform;
 import io.ebean.dbmigration.ddlgeneration.DdlWrite;
 import io.ebean.dbmigration.migration.Migration;
@@ -196,8 +198,9 @@ public class DbMigration {
    *       migration.generateMigration();
    *
    * }</pre>
+   * @return the generated migration or null
    */
-  public void generateMigration() throws IOException {
+  public String generateMigration() throws IOException {
 
     // use this flag to stop other plugins like full DDL generation
     if (!online) {
@@ -218,9 +221,9 @@ public class DbMigration {
 
       String pendingVersion = generatePendingDrop();
       if (pendingVersion != null) {
-        generatePendingDrop(request, pendingVersion);
+        return generatePendingDrop(request, pendingVersion);
       } else {
-        generateDiff(request);
+        return generateDiff(request);
       }
 
     } finally {
@@ -276,7 +279,7 @@ public class DbMigration {
   /**
    * Generate the diff migration.
    */
-  private void generateDiff(Request request) throws IOException {
+  private String generateDiff(Request request) throws IOException {
 
     List<String> pendingDrops = request.getPendingDrops();
     if (!pendingDrops.isEmpty()) {
@@ -286,25 +289,27 @@ public class DbMigration {
     Migration migration = request.createDiffMigration();
     if (migration == null) {
       logger.info("no changes detected - no migration written");
+      return null;
     } else {
       // there were actually changes to write
-      generateMigration(request, migration, null);
+      return generateMigration(request, migration, null);
     }
   }
 
   /**
    * Generate the migration based on the pendingDrops from a prior version.
    */
-  private void generatePendingDrop(Request request, String pendingVersion) throws IOException {
+  private String generatePendingDrop(Request request, String pendingVersion) throws IOException {
 
     Migration migration = request.migrationForPendingDrop(pendingVersion);
 
-    generateMigration(request, migration, pendingVersion);
+    String version = generateMigration(request, migration, pendingVersion);
 
     List<String> pendingDrops = request.getPendingDrops();
     if (!pendingDrops.isEmpty()) {
       logger.info("... remaining pending un-applied drops in versions {}", pendingDrops);
     }
+    return version;
   }
 
   private Request createRequest() {
@@ -358,14 +363,14 @@ public class DbMigration {
     }
   }
 
-  private void generateMigration(Request request, Migration dbMigration, String dropsFor) throws IOException {
+  private String generateMigration(Request request, Migration dbMigration, String dropsFor) throws IOException {
 
     String fullVersion = getFullVersion(request.migrationModel, dropsFor);
 
     logger.info("generating migration:{}", fullVersion);
     if (!writeMigrationXml(dbMigration, request.modelDir, fullVersion)) {
       logger.warn("migration already exists, not generating DDL");
-
+      return null;
     } else {
       if (!platforms.isEmpty()) {
         writeExtraPlatformDdl(fullVersion, request.currentModel, dbMigration, request.migrationDir);
@@ -374,9 +379,10 @@ public class DbMigration {
         // writer needs the current model to provide table/column details for
         // history ddl generation (triggers, history tables etc)
         DdlWrite write = new DdlWrite(new MConfiguration(), request.current);
-        PlatformDdlWriter writer = createDdlWriter(databasePlatform, "");
+        PlatformDdlWriter writer = createDdlWriter(databasePlatform);
         writer.processMigration(dbMigration, write, request.migrationDir, fullVersion);
       }
+      return fullVersion;
     }
   }
 
@@ -431,7 +437,7 @@ public class DbMigration {
 
     for (Pair pair : platforms) {
       DdlWrite platformBuffer = new DdlWrite(new MConfiguration(), currentModel.read());
-      PlatformDdlWriter platformWriter = createDdlWriter(pair);
+      PlatformDdlWriter platformWriter = createDdlWriter(pair.platform);
       File subPath = platformWriter.subPath(writePath, pair.prefix);
       platformWriter.processMigration(dbMigration, platformBuffer, subPath, fullVersion);
 
@@ -439,12 +445,8 @@ public class DbMigration {
     }
   }
 
-  private PlatformDdlWriter createDdlWriter(Pair pair) {
-    return createDdlWriter(pair.platform, pair.prefix);
-  }
-
-  private PlatformDdlWriter createDdlWriter(DatabasePlatform platform, String prefix) {
-    return new PlatformDdlWriter(platform, serverConfig, prefix, migrationConfig);
+  private PlatformDdlWriter createDdlWriter(DatabasePlatform platform) {
+    return new PlatformDdlWriter(platform, serverConfig, migrationConfig);
   }
 
   /**
@@ -519,19 +521,25 @@ public class DbMigration {
     switch (platform) {
       case H2:
         return new H2Platform();
+      case HSQLDB:
+        return new HsqldbPlatform();
       case POSTGRES:
         return new PostgresPlatform();
       case MYSQL:
         return new MySqlPlatform();
       case ORACLE:
         return new OraclePlatform();
+      case SQLANYWHERE:
+        return new SqlAnywherePlatform();
       case SQLSERVER:
         return new SqlServerPlatform();
       case DB2:
         return new DB2Platform();
       case SQLITE:
         return new SQLitePlatform();
-
+      case GENERIC:
+        return new DatabasePlatform();
+        
       default:
         throw new IllegalArgumentException("Platform missing? " + platform);
     }

src/main/java/io/ebean/dbmigration/DdlGenerator.java

@@ -5,7 +5,7 @@ import io.ebean.config.ServerConfig;
 import io.ebean.dbmigration.model.CurrentModel;
 import io.ebeaninternal.api.SpiEbeanServer;
 import io.ebeaninternal.extraddl.model.ExtraDdlXmlReader;
-import io.ebean.dbmigration.ddl.DdlRunner;
+import io.ebean.migration.ddl.DdlRunner;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/io/ebean/dbmigration/ddlgeneration/BaseDdlHandler.java

@@ -36,6 +36,11 @@ public class BaseDdlHandler implements DdlHandler {
     for (Object change : changeSetChildren) {
       if (change instanceof CreateTable) {
         generate(writer, (CreateTable) change);
+      }
+    }
+    for (Object change : changeSetChildren) {
+      if (change instanceof CreateTable) {
+        // ignore
       } else if (change instanceof DropTable) {
         generate(writer, (DropTable) change);
       } else if (change instanceof AddTableComment) {
@@ -54,6 +59,8 @@ public class BaseDdlHandler implements DdlHandler {
         generate(writer, (AddHistoryTable) change);
       } else if (change instanceof DropHistoryTable) {
         generate(writer, (DropHistoryTable) change);
+      } else {
+        throw new IllegalArgumentException("Unsupported change: " + change);
       }
     }
   }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java

@@ -3,6 +3,8 @@ package io.ebean.dbmigration.ddlgeneration.platform;
 import io.ebean.config.DbConstraintNaming;
 import io.ebean.config.NamingConvention;
 import io.ebean.config.ServerConfig;
+import io.ebean.config.dbplatform.DbHistorySupport;
+import io.ebean.config.dbplatform.DbIdentity;
 import io.ebean.config.dbplatform.IdType;
 import io.ebean.dbmigration.ddlgeneration.DdlBuffer;
 import io.ebean.dbmigration.ddlgeneration.DdlWrite;
@@ -15,6 +17,7 @@ import io.ebean.dbmigration.migration.AlterColumn;
 import io.ebean.dbmigration.migration.Column;
 import io.ebean.dbmigration.migration.CreateIndex;
 import io.ebean.dbmigration.migration.CreateTable;
+import io.ebean.dbmigration.migration.DdlScript;
 import io.ebean.dbmigration.migration.DropColumn;
 import io.ebean.dbmigration.migration.DropHistoryTable;
 import io.ebean.dbmigration.migration.DropIndex;
@@ -27,6 +30,8 @@ import io.ebean.util.StringHelper;
 import java.io.IOException;
 import java.math.BigInteger;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -54,6 +59,8 @@ public class BaseTableDdl implements TableDdl {
    * Used when unique constraints specifically for OneToOne can't be created normally (MsSqlServer).
    */
   protected List<Column> externalUnique = new ArrayList<>();
+  
+  protected List<UniqueConstraint> externalCompoundUnique = new ArrayList<>();
 
   // counters used when constraint names are truncated due to maximum length
   // and these counters are used to keep the constraint name unique
@@ -68,6 +75,121 @@ public class BaseTableDdl implements TableDdl {
    */
   protected Map<String, HistoryTableUpdate> regenerateHistoryTriggers = new LinkedHashMap<>();
 
+  private boolean strict;
+
+  private final boolean sql2011History;
+  
+  /**
+   * Helper class that is used to execute the migration ddl before and after the migration action.
+   */
+  private class DdlMigrationHelp {
+    private List<String> before;
+    private List<String> after;
+    private String tableName;
+    private String columnName;
+    private String defaultValue;
+
+    /**
+     * Constructor for DdlMigrationHelp when adding a NEW column.
+     */
+    DdlMigrationHelp(String tableName, Column column) throws IOException {
+      this.tableName = tableName;
+      this.columnName = column.getName();
+      this.defaultValue = platformDdl.convertDefaultValue(column.getDefaultValue());
+      boolean alterNotNull = Boolean.TRUE.equals(column.isNotnull());
+
+      if (column.getBefore().isEmpty() && alterNotNull && defaultValue == null) {
+        handleStrictError("non-null column has no default value: " + tableName + "." + columnName);
+      }
+      
+      before = getScriptsForPlatform(column.getBefore(), platformDdl.getPlatform().getName());
+      after = getScriptsForPlatform(column.getAfter(), platformDdl.getPlatform().getName());
+
+    }
+
+    /**
+     * Constructor for DdlMigrationHelp when altering a column.
+     */
+    DdlMigrationHelp(AlterColumn alter) throws IOException {
+      this.tableName = alter.getTableName();
+      this.columnName = alter.getColumnName();
+      
+      String tmp = alter.getDefaultValue() != null ? alter.getDefaultValue() : alter.getCurrentDefaultValue();
+      this.defaultValue = platformDdl.convertDefaultValue(tmp);
+          
+      boolean alterNotNull = Boolean.TRUE.equals(alter.isNotnull());
+      // here we add the platform's default update script
+      if (alter.getBefore().isEmpty() && alterNotNull) {
+        if (defaultValue == null) {
+          handleStrictError("non-null column has no default value: " + tableName + "." + columnName);
+        }
+        before = Arrays.asList(platformDdl.getUpdateNullWithDefault());
+      } else {
+        before = getScriptsForPlatform(alter.getBefore(), platformDdl.getPlatform().getName());
+      }
+      
+      after = getScriptsForPlatform(alter.getAfter(), platformDdl.getPlatform().getName());
+      
+    }
+    
+    public void writeBefore(DdlBuffer buffer) throws IOException {
+      if (!before.isEmpty()) {
+        buffer.end();
+      }
+      for (String ddlScript : before) {
+        buffer.append(translate(ddlScript, tableName, columnName, this.defaultValue));
+        buffer.endOfStatement();
+      }
+    }
+    
+    public void writeAfter(DdlBuffer buffer) throws IOException {
+      // here we run postmigration scripts
+      for (String ddlScript : after) {
+        buffer.append(translate(ddlScript, tableName, columnName, defaultValue));
+        buffer.endOfStatement();
+      }
+      if (!after.isEmpty()) {
+        buffer.end();
+      }
+    }
+
+    private List<String> getScriptsForPlatform(List<DdlScript> scripts, String searchPlatform) {
+      List<String> ret = Collections.emptyList();
+      for (DdlScript script : scripts) {
+        if (script.getPlatforms() == null || script.getPlatforms().isEmpty()) {
+          ret = script.getDdl();
+        } else for (String platform : StringHelper.splitNames(script.getPlatforms())) {
+          if (platform.equals(searchPlatform)) {
+           return script.getDdl();
+          }
+        }
+      }
+      return ret;
+    }
+
+    /**
+     * Replaces Table name (${table}), Column name (${column}) and default value (${default}) in DDL.
+     */
+    private String translate(String ddl, String tableName, String columnName, String defaultValue) {
+      String ret = StringHelper.replaceString(ddl, "${table}", tableName);
+      ret = StringHelper.replaceString(ret, "${column}", columnName);
+      return StringHelper.replaceString(ret, "${default}", defaultValue);
+    }
+
+    private void handleStrictError(String message) {
+      if (strict) {
+        throw new IllegalArgumentException(message);
+      } else {
+        System.err.println("Error in DDL: " + message);
+      }
+    }
+    
+    public String getDefaultValue() {
+      return defaultValue;
+    }
+
+  }
+
   /**
    * Construct with a naming convention and platform specific DDL.
    */
@@ -77,6 +199,9 @@ public class BaseTableDdl implements TableDdl {
     this.historyTableSuffix = serverConfig.getHistoryTableSuffix();
     this.platformDdl = platformDdl;
     this.platformDdl.configure(serverConfig);
+    this.strict = true; // TODO RPr serverConfig.getMigrationConfig().isStrict();
+    DbHistorySupport hist = platformDdl.getPlatform().getHistorySupport();
+    this.sql2011History = hist != null && hist.isStandardsBased();
   }
 
   /**
@@ -85,6 +210,7 @@ public class BaseTableDdl implements TableDdl {
   protected void reset() {
     indexSet.clear();
     externalUnique.clear();
+    externalCompoundUnique.clear();
     countCheck = 0;
     countUnique = 0;
     countForeignKey = 0;
@@ -204,9 +330,24 @@ public class BaseTableDdl implements TableDdl {
     String tableName = createTable.getName();
     for (Column col : externalUnique) {
       String uqName = col.getUniqueOneToOne();
+      if (uqName == null) {
+        uqName = col.getUnique();
+      }
       String[] columnNames = {col.getName()};
       write.apply()
-        .append(platformDdl.alterTableAddUniqueConstraint(tableName, uqName, columnNames))
+        .append(platformDdl.alterTableAddUniqueConstraint(tableName, uqName, columnNames, Boolean.TRUE.equals(col.isNotnull())))
+        .endOfStatement();
+
+      write.dropAllForeignKeys()
+        .append(platformDdl.dropIndex(uqName, tableName))
+        .endOfStatement();
+    }
+    
+    for (UniqueConstraint constraint : externalCompoundUnique) {
+      String uqName = constraint.getName();
+      String[] columnNames = StringHelper.delimitedToArray(constraint.getColumnNames(), ",", false);
+      write.apply()
+        .append(platformDdl.alterTableAddUniqueConstraint(tableName, uqName, columnNames, false)) // TODO: check if nullable
         .endOfStatement();
 
       write.dropAllForeignKeys()
@@ -377,6 +518,14 @@ public class BaseTableDdl implements TableDdl {
     buffer.append(platformDdl.dropTable(tableName)).endOfStatement();
   }
 
+  /**
+   * Add 'drop sequence' statement to the buffer.
+   */
+  protected void dropSequence(DdlBuffer buffer, String sequenceName) throws IOException {
+
+    buffer.append(platformDdl.dropSequence(sequenceName)).endOfStatement();
+  }
+  
   /**
    * Write all the check constraints.
    */
@@ -406,12 +555,17 @@ public class BaseTableDdl implements TableDdl {
   protected void writeCompoundUniqueConstraints(DdlBuffer apply, CreateTable createTable) throws IOException {
 
     List<UniqueConstraint> uniqueConstraints = createTable.getUniqueConstraint();
+    boolean inlineUniqueWhenNull = platformDdl.isInlineUniqueWhenNullable();
     for (UniqueConstraint uniqueConstraint : uniqueConstraints) {
-      String uqName = uniqueConstraint.getName();
-      String[] columns = toColumnNamesSplit(uniqueConstraint.getColumnNames());
-      apply.append(",").newLine();
-      apply.append("  constraint ").append(uqName).append(" unique");
-      appendColumns(columns, apply);
+       if (inlineUniqueWhenNull) {
+        String uqName = uniqueConstraint.getName();
+        String[] columns = toColumnNamesSplit(uniqueConstraint.getColumnNames());
+        apply.append(",").newLine();
+        apply.append("  constraint ").append(uqName).append(" unique");
+        appendColumns(columns, apply);
+      } else {
+        externalCompoundUnique.add(uniqueConstraint);
+      }
     }
   }
 
@@ -420,17 +574,18 @@ public class BaseTableDdl implements TableDdl {
    */
   protected void writeUniqueConstraints(DdlBuffer apply, CreateTable createTable) throws IOException {
 
-    boolean inlineUniqueOneToOne = platformDdl.isInlineUniqueOneToOne();
+    boolean inlineUniqueWhenNullable = platformDdl.isInlineUniqueWhenNullable();
 
     List<Column> columns = createTable.getColumn();
     for (Column column : columns) {
-      if (hasValue(column.getUnique()) || (inlineUniqueOneToOne && hasValue(column.getUniqueOneToOne()))) {
-        // normal mechanism for adding unique constraint
-        inlineUniqueConstraintSingle(apply, column);
-
-      } else if (!inlineUniqueOneToOne && hasValue(column.getUniqueOneToOne())) {
-        // MsSqlServer specific mechanism for adding unique constraints (that allow nulls)
-        externalUnique.add(column);
+      if (hasValue(column.getUnique()) || hasValue(column.getUniqueOneToOne())) {
+        if (Boolean.TRUE.equals(column.isNotnull()) || inlineUniqueWhenNullable) {
+          // normal mechanism for adding unique constraint
+          inlineUniqueConstraintSingle(apply, column);
+        } else {
+          // MsSqlServer & DB2 specific mechanism for adding unique constraints (that allow nulls)
+          externalUnique.add(column);
+        }
       }
     }
   }
@@ -574,7 +729,7 @@ public class BaseTableDdl implements TableDdl {
       alterTableAddColumn(writer.apply(), tableName, column, false);
     }
 
-    if (isTrue(addColumn.isWithHistory())) {
+    if (isTrue(addColumn.isWithHistory()) && !sql2011History) {
       // make same changes to the history table
       String historyTable = historyTable(tableName);
       for (Column column : columns) {
@@ -600,6 +755,15 @@ public class BaseTableDdl implements TableDdl {
   public void generate(DdlWrite writer, DropTable dropTable) throws IOException {
 
     dropTable(writer.apply(), dropTable.getName());
+
+    if (hasValue(dropTable.getSequenceCol())
+        && platformDdl.getPlatform().getDbIdentity().isSupportsSequence()) {
+      String sequenceName = dropTable.getSequenceName();
+      if (!hasValue(sequenceName)) {
+        sequenceName = namingConvention.getSequenceName(dropTable.getName(), dropTable.getSequenceCol());
+      }
+      dropSequence(writer.apply(), sequenceName);
+    }
   }
 
   /**
@@ -611,7 +775,7 @@ public class BaseTableDdl implements TableDdl {
     String tableName = dropColumn.getTableName();
 
     alterTableDropColumn(writer.apply(), tableName, dropColumn.getColumnName());
-    if (isTrue(dropColumn.isWithHistory())) {
+    if (isTrue(dropColumn.isWithHistory()) && !sql2011History) {
       // also drop from the history table
       regenerateHistoryTriggers(tableName, HistoryTableUpdate.Change.DROP, dropColumn.getColumnName());
       alterTableDropColumn(writer.apply(), historyTable(tableName), dropColumn.getColumnName());
@@ -625,7 +789,9 @@ public class BaseTableDdl implements TableDdl {
    */
   @Override
   public void generate(DdlWrite writer, AlterColumn alterColumn) throws IOException {
-
+    DdlMigrationHelp ddlHelp = new DdlMigrationHelp(alterColumn);
+    ddlHelp.writeBefore(writer.apply());
+    
     if (isTrue(alterColumn.isHistoryExclude())) {
       regenerateHistoryTriggers(alterColumn.getTableName(), HistoryTableUpdate.Change.EXCLUDE, alterColumn.getColumnName());
     } else if (isFalse(alterColumn.isHistoryExclude())) {
@@ -678,6 +844,7 @@ public class BaseTableDdl implements TableDdl {
       // add constraint last (after potential type change)
       addCheckConstraint(writer, alterColumn);
     }
+    ddlHelp.writeAfter(writer.apply());
   }
 
   private void alterColumnComment(DdlWrite writer, AlterColumn alterColumn) throws IOException {
@@ -696,11 +863,7 @@ public class BaseTableDdl implements TableDdl {
    */
   protected void regenerateHistoryTriggers(String baseTableName, HistoryTableUpdate.Change change, String column) {
 
-    HistoryTableUpdate update = regenerateHistoryTriggers.get(baseTableName);
-    if (update == null) {
-      update = new HistoryTableUpdate(baseTableName);
-      regenerateHistoryTriggers.put(baseTableName, update);
-    }
+    HistoryTableUpdate update = regenerateHistoryTriggers.computeIfAbsent(baseTableName, HistoryTableUpdate::new);
     update.add(change, column);
   }
 
@@ -713,7 +876,7 @@ public class BaseTableDdl implements TableDdl {
     if (hasValue(ddl)) {
       writer.apply().append(ddl).endOfStatement();
 
-      if (isTrue(alter.isWithHistory()) && alter.getType() != null) {
+      if (isTrue(alter.isWithHistory()) && alter.getType() != null && !sql2011History) {
         // mysql and sql server column type change allowing nulls in the history table column
         AlterColumn alterHistoryColumn = new AlterColumn();
         alterHistoryColumn.setTableName(historyTable(alter.getTableName()));
@@ -764,7 +927,7 @@ public class BaseTableDdl implements TableDdl {
     String ddl = platformDdl.alterColumnType(alter.getTableName(), alter.getColumnName(), alter.getType());
     if (hasValue(ddl)) {
       writer.apply().append(ddl).endOfStatement();
-      if (isTrue(alter.isWithHistory())) {
+      if (isTrue(alter.isWithHistory()) && !sql2011History) {
         // apply same type change to matching column in the history table
         ddl = platformDdl.alterColumnType(historyTable(alter.getTableName()), alter.getColumnName(), alter.getType());
         writer.apply().append(ddl).endOfStatement();
@@ -818,9 +981,9 @@ public class BaseTableDdl implements TableDdl {
   protected void addUniqueConstraint(DdlWrite writer, AlterColumn alter, String uqName) throws IOException {
 
     String[] cols = {alter.getColumnName()};
-
+    boolean notNull = alter.isNotnull() != null ? alter.isNotnull() : Boolean.TRUE.equals(alter.isNotnull());
     writer.apply()
-      .append(platformDdl.alterTableAddUniqueConstraint(alter.getTableName(), uqName, cols))
+      .append(platformDdl.alterTableAddUniqueConstraint(alter.getTableName(), uqName, cols, notNull))
       .endOfStatement();
 
     writer.dropAllForeignKeys()
@@ -830,27 +993,20 @@ public class BaseTableDdl implements TableDdl {
 
 
   protected void alterTableDropColumn(DdlBuffer buffer, String tableName, String columnName) throws IOException {
-
-    buffer.append("alter table ").append(tableName).append(" drop column ").append(columnName)
-      .endOfStatement();
+    platformDdl.alterTableDropColumn(buffer, tableName, columnName);
   }
 
   protected void alterTableAddColumn(DdlBuffer buffer, String tableName, Column column, boolean onHistoryTable) throws IOException {
-
-    String convertedType = platformDdl.convert(column.getType(), false);
-    buffer.append("alter table ").append(tableName)
-      .append(" add column ").append(column.getName())
-      .append(" ").append(convertedType);
-
+    DdlMigrationHelp help = new DdlMigrationHelp(tableName, column);    
     if (!onHistoryTable) {
-      if (isTrue(column.isNotnull())) {
-        buffer.append(" not null");
-      }
-      if (hasValue(column.getCheckConstraint())) {
-        buffer.append(" ").append(column.getCheckConstraint());
-      }
+      help.writeBefore(buffer);
+    }
+    
+    platformDdl.alterTableAddColumn(buffer, tableName, column, onHistoryTable, help.getDefaultValue());
+    
+    if (!onHistoryTable) {
+      help.writeAfter(buffer);
     }
-    buffer.endOfStatement();
   }
 
   protected boolean isFalse(Boolean value) {

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/DB2Ddl.java

@@ -9,7 +9,21 @@ public class DB2Ddl extends PlatformDdl {
 
   public DB2Ddl(DatabasePlatform platform) {
     super(platform);
+    this.dropTableIfExists = "drop table ";
+    this.dropSequenceIfExists = "drop sequence ";
+    this.dropConstraintIfExists = "drop constraint";
+    this.dropIndexIfExists = "drop index ";
     this.identitySuffix = " generated by default as identity";
+    this.inlineUniqueWhenNullable = false;
+  }
+  
+  public String alterTableAddUniqueConstraint(String tableName, String uqName, String[] columns, boolean notNull) {
+    if (notNull) {
+      return super.alterTableAddUniqueConstraint(tableName, uqName, columns, true);
+    } else {
+      // Hmm: Complex workaround: https://www.ibm.com/developerworks/mydeveloperworks/blogs/SQLTips4DB2LUW/entry/unique_where_not_null_indexes26?lang=en
+      return "-- NOT SUPPORTED " + super.alterTableAddUniqueConstraint(tableName, uqName, columns, true);
+    }
   }
 
 }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/DdlHelp.java

@@ -0,0 +1,22 @@
+package io.ebean.dbmigration.ddlgeneration.platform;
+
+public class DdlHelp {
+  public static final String DROP_DEFAULT = "DROP DEFAULT";
+  
+  public static final String DROP_COMMENT = "DROP COMMENT";
+  
+  /**
+   * Return true if the default value is the special DROP DEFAULT value.
+   */
+  public static boolean isDropDefault(String defaultValue) {
+    return DROP_DEFAULT.equals(defaultValue);
+  }
+  
+  /**
+   * Return true if the default value is the special DROP DEFAULT value.
+   */
+  public static boolean isDropComment(String comment) {
+    return DROP_COMMENT.equals(comment);
+  }
+  
+}

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/H2Ddl.java

@@ -12,4 +12,8 @@ public class H2Ddl extends PlatformDdl {
     this.historyDdl = new H2HistoryDdl();
   }
 
+  @Override
+  protected String convertArrayType(String logicalArrayType) {
+    return "array";
+  }
 }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/MySqlDdl.java

@@ -59,7 +59,7 @@ public class MySqlDdl extends PlatformDdl {
   @Override
   public String alterColumnDefaultValue(String tableName, String columnName, String defaultValue) {
 
-    String suffix = isDropDefault(defaultValue) ? columnDropDefault : columnSetDefault + " " + defaultValue;
+    String suffix = DdlHelp.isDropDefault(defaultValue) ? columnDropDefault : columnSetDefault + " " + defaultValue;
 
     // use alter
     return "alter table " + tableName + " alter " + columnName + " " + suffix;
@@ -67,10 +67,13 @@ public class MySqlDdl extends PlatformDdl {
 
   @Override
   public String alterColumnBaseAttributes(AlterColumn alter) {
-
+    if (DdlHelp.isDropDefault(alter.getDefaultValue())) {
+      return null;
+    }
     String tableName = alter.getTableName();
     String columnName = alter.getColumnName();
     String type = alter.getType() != null ? alter.getType() : alter.getCurrentType();
+    type = convert(type, false);
     boolean notnull = (alter.isNotnull() != null) ? alter.isNotnull() : Boolean.TRUE.equals(alter.isCurrentNotnull());
     String notnullClause = notnull ? " not null" : "";
 
@@ -100,4 +103,11 @@ public class MySqlDdl extends PlatformDdl {
     apply.append(" comment='").append(tableComment).append("'");
   }
 
+  /**
+   * Add table comment as a separate statement (from the create table statement).
+   */
+  @Override
+  public void addTableComment(DdlBuffer apply, String tableName, String tableComment) throws IOException {
+    apply.append(String.format("alter table %s comment = '%s'", tableName, tableComment)).endOfStatement();
+  }
 }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java

@@ -17,6 +17,9 @@ import io.ebean.dbmigration.migration.Column;
 import io.ebean.dbmigration.migration.DropHistoryTable;
 import io.ebean.dbmigration.migration.IdentityType;
 import io.ebean.dbmigration.model.MTable;
+import io.ebean.util.StringHelper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.util.List;
@@ -26,6 +29,8 @@ import java.util.List;
  */
 public class PlatformDdl {
 
+  private static final Logger logger = LoggerFactory.getLogger(PlatformDdl.class);
+
   protected final DatabasePlatform platform;
 
   protected PlatformHistoryDdl historyDdl = new NoHistorySupportDdl();
@@ -75,6 +80,8 @@ public class PlatformDdl {
 
   protected String addConstraint = "add constraint";
 
+  protected String addColumn = "add column";
+
   protected String columnSetType = "";
 
   protected String columnSetDefault = "set default";
@@ -85,10 +92,12 @@ public class PlatformDdl {
 
   protected String columnSetNull = "set null";
 
+  protected String updateNullWithDefault = "update ${table} set ${column} = ${default} where ${column} is null";
+
   /**
    * Set false for MsSqlServer to allow multiple nulls for OneToOne mapping.
    */
-  protected boolean inlineUniqueOneToOne = true;
+  protected boolean inlineUniqueWhenNullable = true;
 
   protected DbConstraintNaming naming;
 
@@ -99,6 +108,8 @@ public class PlatformDdl {
 
   protected final DbDefaultValue dbDefaultValue;
 
+  protected String fallbackArrayType = "varchar(1000)";
+
   public PlatformDdl(DatabasePlatform platform) {
     this.platform = platform;
     this.dbIdentity = platform.getDbIdentity();
@@ -176,7 +187,7 @@ public class PlatformDdl {
     buffer.append("  ");
     buffer.append(lowerColumnName(column.getName()), 29);
     buffer.append(platformType);
-    if (!typeContainsDefault(platformType)) {
+    if (!Boolean.TRUE.equals(column.isPrimaryKey()) && !typeContainsDefault(platformType)) {
       String defaultValue = convertDefaultValue(column.getDefaultValue());
       if (defaultValue != null) {
         buffer.append(" default ").append(defaultValue);
@@ -200,7 +211,7 @@ public class PlatformDdl {
   /**
    * Convert the DB column default literal to platform specific.
    */
-  private String convertDefaultValue(String dbDefault) {
+  public String convertDefaultValue(String dbDefault) {
     return dbDefaultValue.convert(dbDefault);
   }
 
@@ -215,10 +226,24 @@ public class PlatformDdl {
    * Convert the standard type to the platform specific type.
    */
   public String convert(String type, boolean identity) {
+    if (type.contains("[]")) {
+      return convertArrayType(type);
+    }
     String platformType = typeConverter.convert(type);
     return identity ? asIdentityColumn(platformType) : platformType;
   }
 
+  /**
+   * Convert the logical array type to a db platform specific type to support the array data.
+   */
+  protected String convertArrayType(String logicalArrayType) {
+    if (logicalArrayType.endsWith("]")) {
+      return fallbackArrayType;
+    }
+    int colonPos = logicalArrayType.lastIndexOf(']');
+    return "varchar" + logicalArrayType.substring(colonPos + 1);
+  }
+
   /**
    * Add history support to this table using the platform specific mechanism.
    */
@@ -352,7 +377,7 @@ public class PlatformDdl {
    * <p>
    * Overridden by MsSqlServer for specific null handling on unique constraints.
    */
-  public String alterTableAddUniqueConstraint(String tableName, String uqName, String[] columns) {
+  public String alterTableAddUniqueConstraint(String tableName, String uqName, String[] columns, boolean notNull) {
 
     StringBuilder buffer = new StringBuilder(90);
     buffer.append("alter table ").append(tableName).append(" add constraint ").append(uqName).append(" unique ");
@@ -360,12 +385,52 @@ public class PlatformDdl {
     return buffer.toString();
   }
 
+  public void alterTableAddColumn(DdlBuffer buffer, String tableName, Column column, boolean onHistoryTable, String defaultValue) throws IOException {
+
+    String convertedType = convert(column.getType(), false);
+
+    buffer.append("alter table ").append(tableName)
+      .append(" ").append(addColumn).append(" ").append(column.getName())
+      .append(" ").append(convertedType);
+
+    if (!onHistoryTable) {
+      if (isTrue(column.isNotnull())) {
+        buffer.append(" not null");
+      }
+
+      if (defaultValue != null) {
+        if (typeContainsDefault(convertedType)) {
+          logger.error("Cannot set default value for '" + tableName + "." + column.getName() + "'");
+        } else {
+          buffer.append(" default ");
+          buffer.append(defaultValue);
+        }
+      }
+      buffer.endOfStatement();
+
+      // check constraints cannot be added in one statement for h2
+      if (!StringHelper.isNull(column.getCheckConstraint())) {
+        String ddl = alterTableAddCheckConstraint(tableName, column.getCheckConstraintName(), column.getCheckConstraint());
+        buffer.append(ddl).endOfStatement();
+      }
+    } else {
+      buffer.endOfStatement();
+    }
+
+  }
+  
+  public void alterTableDropColumn(DdlBuffer buffer, String tableName, String columnName) throws IOException {
+    buffer.append("alter table ").append(tableName).append(" drop column ").append(columnName)
+    .endOfStatement();
+  }
+
   /**
-   * Return true if unique constraints for OneToOne can be inlined as normal.
-   * Returns false for MsSqlServer due to it's null handling for unique constraints.
+   * Return true if unique constraints for nullable columns can be inlined as normal.
+   * Returns false for MsSqlServer & DB2 due to it's not possible to to put a constraint
+   * on a nullable column
    */
-  public boolean isInlineUniqueOneToOne() {
-    return inlineUniqueOneToOne;
+  public boolean isInlineUniqueWhenNullable() {
+    return inlineUniqueWhenNullable;
   }
 
   /**
@@ -376,7 +441,7 @@ public class PlatformDdl {
    */
   public String alterColumnType(String tableName, String columnName, String type) {
 
-    return "alter table " + tableName + " " + alterColumn + " " + columnName + " " + columnSetType + type;
+    return "alter table " + tableName + " " + alterColumn + " " + columnName + " " + columnSetType + convert(type, false);
   }
 
   /**
@@ -399,19 +464,11 @@ public class PlatformDdl {
     return "alter table " + tableName + " " + addConstraint + " " + checkConstraintName + " " + checkConstraint;
   }
 
-  /**
-   * Return true if the default value is the special DROP DEFAULT value.
-   */
-  public boolean isDropDefault(String defaultValue) {
-    return "DROP DEFAULT".equals(defaultValue);
-  }
-
   /**
    * Alter column setting the default value.
    */
   public String alterColumnDefaultValue(String tableName, String columnName, String defaultValue) {
-
-    String suffix = isDropDefault(defaultValue) ? columnDropDefault : columnSetDefault + " " + defaultValue;
+    String suffix = DdlHelp.isDropDefault(defaultValue) ? columnDropDefault : columnSetDefault + " " + defaultValue;
     return "alter table " + tableName + " " + alterColumn + " " + columnName + " " + suffix;
   }
 
@@ -464,6 +521,13 @@ public class PlatformDdl {
     return naming.lowerColumnName(name);
   }
 
+  public DatabasePlatform getPlatform() {
+    return platform;
+  }
+
+  public String getUpdateNullWithDefault() {
+    return updateNullWithDefault;
+  }
 
   /**
    * Null safe Boolean true test.
@@ -483,15 +547,19 @@ public class PlatformDdl {
    * Add table comment as a separate statement (from the create table statement).
    */
   public void addTableComment(DdlBuffer apply, String tableName, String tableComment) throws IOException {
-
+    if (DdlHelp.isDropComment(tableComment)) {
+      tableComment = "";
+    }
     apply.append(String.format("comment on table %s is '%s'", tableName, tableComment)).endOfStatement();
   }
-
+  
   /**
    * Add column comment as a separate statement.
    */
   public void addColumnComment(DdlBuffer apply, String table, String column, String comment) throws IOException {
-
+    if (DdlHelp.isDropComment(comment)) {
+      comment = "";
+    }
     apply.append(String.format("comment on column %s.%s is '%s'", table, column, comment)).endOfStatement();
   }
 }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/PostgresDdl.java

@@ -16,6 +16,17 @@ public class PostgresDdl extends PlatformDdl {
     this.columnSetNull = "drop not null";
   }
 
+  @Override
+  protected String convertArrayType(String logicalArrayType) {
+    int colonPos = logicalArrayType.lastIndexOf(']');
+    if (colonPos == -1) {
+      return logicalArrayType;
+    } else {
+      // trim of the fallback varchar length
+      return logicalArrayType.substring(0, colonPos + 1);
+    }
+  }
+
   /**
    * Map bigint, integer and smallint into their equivalent serial types.
    */

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/SqlServerDdl.java

@@ -15,7 +15,9 @@ public class SqlServerDdl extends PlatformDdl {
     super(platform);
     this.identitySuffix = " identity(1,1)";
     this.foreignKeyRestrict = "";
-    this.inlineUniqueOneToOne = false;
+    this.alterTableIfExists = "";
+    this.addColumn = "add";
+    this.inlineUniqueWhenNullable = false;
     this.columnSetDefault = "add default";
     this.dropConstraintIfExists = "drop constraint";
     this.historyDdl = new SqlServerHistoryDdl();
@@ -23,20 +25,44 @@ public class SqlServerDdl extends PlatformDdl {
 
   @Override
   public String dropTable(String tableName) {
-    return "IF OBJECT_ID('" + tableName + "', 'U') IS NOT NULL drop table " + tableName;
+    StringBuilder buffer = new StringBuilder();
+    buffer.append("IF OBJECT_ID('");
+    buffer.append(tableName);
+    buffer.append("', 'U') IS NOT NULL drop table ");
+    buffer.append(tableName);
+    return buffer.toString();
   }
 
   @Override
   public String alterTableDropForeignKey(String tableName, String fkName) {
-    return "IF OBJECT_ID('" + fkName + "', 'F') IS NOT NULL " + super.alterTableDropForeignKey(tableName, fkName);
+    int pos = tableName.lastIndexOf('.');
+    String objectId = fkName;
+    if (pos != -1) {
+      objectId = tableName.substring(0, pos + 1) + fkName;
+    } 
+    return "IF OBJECT_ID('" + objectId + "', 'F') IS NOT NULL " + super.alterTableDropForeignKey(tableName, fkName);
+  }
+  
+  @Override
+  public String dropSequence(String sequenceName) {
+    return "IF OBJECT_ID('" + sequenceName + "', 'SO') IS NOT NULL drop sequence " + sequenceName; 
   }
 
+  @Override
+  public String dropIndex(String indexName, String tableName) {
+    return "IF EXISTS (SELECT name FROM sys.indexes WHERE object_id = OBJECT_ID('" + tableName +"','U') AND name = '" + indexName + "') drop index " + indexName + " ON " + tableName;
+  }
   /**
    * MsSqlServer specific null handling on unique constraints.
    */
   @Override
-  public String alterTableAddUniqueConstraint(String tableName, String uqName, String[] columns) {
-
+  public String alterTableAddUniqueConstraint(String tableName, String uqName, String[] columns, boolean notNull) {
+    if (notNull) {
+      return super.alterTableAddUniqueConstraint(tableName, uqName, columns, notNull);
+    }
+    if (uqName == null) {
+      throw new NullPointerException();
+    }
     // issues#233
     String start = "create unique nonclustered index " + uqName + " on " + tableName + "(";
     StringBuilder sb = new StringBuilder(start);
@@ -48,32 +74,89 @@ public class SqlServerDdl extends PlatformDdl {
       sb.append(columns[i]);
     }
     sb.append(") where");
+    String sep = " ";
     for (String column : columns) {
-      sb.append(" ").append(column).append(" is not null");
+      sb.append(sep).append(column).append(" is not null");
+      sep = " and ";
+    }
+    return sb.toString();
+  }
+  
+  public String alterTableDropConstraint(String tableName, String constraintName) {
+    StringBuilder sb = new StringBuilder();
+    sb.append("IF (OBJECT_ID('").append(constraintName).append("', 'C') IS NOT NULL) ");
+    sb.append(super.alterTableDropConstraint(tableName, constraintName));
+    return sb.toString();
+  }
+  /**
+   * Drop a unique constraint from the table (Sometimes this is an index).
+   */
+  @Override
+  public String alterTableDropUniqueConstraint(String tableName, String uniqueConstraintName) {
+    StringBuilder sb = new StringBuilder();
+    sb.append("IF (OBJECT_ID('").append(uniqueConstraintName).append("', 'UQ') IS NOT NULL) ");
+    sb.append(super.alterTableDropUniqueConstraint(tableName, uniqueConstraintName)).append(";\n");
+    sb.append(dropIndex(uniqueConstraintName, tableName));
+    return sb.toString();
+  }
+  /**
+   * Generate and return the create sequence DDL.
+   */
+  @Override
+  public String createSequence(String sequenceName, int initialValue, int allocationSize) {
+
+    StringBuilder sb = new StringBuilder("create sequence ");
+    sb.append(sequenceName);
+    sb.append(" as bigint ");
+    if (initialValue > 1) {
+      sb.append(" start with ").append(initialValue);
+    } else {
+      sb.append(" start with 1 ");
+    }
+    if (allocationSize > 0 && allocationSize != 50) {
+      // at this stage ignoring allocationSize 50 as this is the 'default' and
+      // not consistent with the way Ebean batch fetches sequence values
+      sb.append(" increment by ").append(allocationSize);
+    }
+    sb.append(";");
+    return sb.toString();
+  }
+  
+  @Override
+  public String alterColumnDefaultValue(String tableName, String columnName, String defaultValue) {
+    // Unfortunately, the SqlServer creates default values with a random name.
+    // You can specify a name in DDL, but this does not work in conjunction with
+    // temporal tables in certain cases. So we have to delete the constraint with
+    // a rather complex statement.
+    StringBuilder sb = new StringBuilder();
+    if (DdlHelp.isDropDefault(defaultValue)) {
+      sb.append("delimiter $$\n");
+      sb.append("DECLARE @Tmp nvarchar(200);");
+      sb.append("select @Tmp = t1.name  from sys.default_constraints t1\n");
+      sb.append("  join sys.columns t2 on t1.object_id = t2.default_object_id\n");
+      sb.append("  where t1.parent_object_id = OBJECT_ID('").append(tableName)
+        .append("') and t2.name = '").append(columnName).append("';\n");
+      sb.append("if @Tmp is not null EXEC('alter table ").append(tableName).append(" drop constraint ' + @Tmp)$$");
+    } else {
+      sb.append("alter table ").append(tableName);
+      sb.append(" add default ").append(defaultValue).append(" for ").append(columnName);
     }
     return sb.toString();
   }
 
-  @Override
-  public String alterColumnDefaultValue(String tableName, String columnName, String defaultValue) {
-
-    if (isDropDefault(defaultValue)) {
-      return "-- alter table " + tableName + " drop constraint <unknown>  -- find the appropriate constraint for default value on column " + columnName;
-    } else {
-      return "alter table " + tableName + " add default " + defaultValue + " for " + columnName;
-    }
-  }
-
   @Override
   public String alterColumnBaseAttributes(AlterColumn alter) {
-
+    if (DdlHelp.isDropDefault(alter.getDefaultValue())) {
+      return null;
+    }
     String tableName = alter.getTableName();
     String columnName = alter.getColumnName();
     String type = alter.getType() != null ? alter.getType() : alter.getCurrentType();
+    type = convert(type, false);
     boolean notnull = (alter.isNotnull() != null) ? alter.isNotnull() : Boolean.TRUE.equals(alter.isCurrentNotnull());
     String notnullClause = notnull ? " not null" : "";
 
-    return "alter table " + tableName + " alter column " + columnName + " " + type + notnullClause;
+    return "alter table " + tableName + " " + alterColumn + " " + columnName + " " + type + notnullClause;
   }
 
   @Override
@@ -107,4 +190,28 @@ public class SqlServerDdl extends PlatformDdl {
 
     // do nothing for MS SQL Server (cause it requires stored procedures etc)
   }
+  
+  /**
+   * It is rather complex to delete a column on SqlServer as there must not exist any references
+   * (constraints, default values, indices and foreign keys). The list is not yet complete, as
+   * indices over multiple columns will not yet deleted.
+   * (This may be changed to delete all refering objects by using the sys.* tables later)
+   */
+  @Override
+  public void alterTableDropColumn(DdlBuffer buffer, String tableName, String columnName) throws IOException {
+    buffer.append("-- drop column ").append(tableName).append(".").append(columnName).endOfStatement();
+    
+    buffer.append(alterTableDropUniqueConstraint(tableName, naming.uniqueConstraintName(tableName, columnName)));
+    buffer.endOfStatement();
+    buffer.append(alterColumnDefaultValue(tableName, columnName, DdlHelp.DROP_DEFAULT));
+    buffer.endOfStatement();
+    buffer.append(alterTableDropConstraint(tableName, naming.checkConstraintName(tableName, columnName)));
+    buffer.endOfStatement();
+    buffer.append(dropIndex(naming.indexName(tableName, columnName), tableName));
+    buffer.endOfStatement();
+    buffer.append(alterTableDropForeignKey(tableName, naming.foreignKeyConstraintName(tableName, columnName)));
+    buffer.endOfStatement();
+    super.alterTableDropColumn(buffer, tableName, columnName);
+  }
+  
 }

src/main/java/io/ebean/dbmigration/ddlgeneration/platform/SqlServerHistoryDdl.java

@@ -1,5 +1,6 @@
 package io.ebean.dbmigration.ddlgeneration.platform;
 
+import io.ebean.config.DbConstraintNaming;
 import io.ebean.config.ServerConfig;
 import io.ebean.dbmigration.ddlgeneration.DdlBuffer;
 import io.ebean.dbmigration.ddlgeneration.DdlWrite;
@@ -16,11 +17,13 @@ public class SqlServerHistoryDdl implements PlatformHistoryDdl {
 
   private String systemPeriodStart;
   private String systemPeriodEnd;
+  private PlatformDdl platformDdl;
 
   @Override
   public void configure(ServerConfig serverConfig, PlatformDdl platformDdl) {
     this.systemPeriodStart = serverConfig.getAsOfSysPeriod() + "From";
     this.systemPeriodEnd = serverConfig.getAsOfSysPeriod() + "To";
+    this.platformDdl = platformDdl;
   }
 
   @Override
@@ -33,19 +36,38 @@ public class SqlServerHistoryDdl implements PlatformHistoryDdl {
     DdlBuffer apply = writer.applyHistory();
     apply.append("alter table ").append(baseTable).newLine()
       .append("    add ").append(systemPeriodStart).append(" datetime2 GENERATED ALWAYS AS ROW START NOT NULL DEFAULT SYSUTCDATETIME(),").newLine()
-      .append("        ").append(systemPeriodEnd).append("   datetime2 GENERATED ALWAYS AS ROW END   NOT NULL,").newLine()
-      .append("period for system_time (").append(systemPeriodStart).append("From, ").append(systemPeriodEnd).append("To)").endOfStatement();
+      .append("        ").append(systemPeriodEnd).append("   datetime2 GENERATED ALWAYS AS ROW END   NOT NULL DEFAULT '9999-12-31T23:59:59.9999999',").newLine()
+      .append("period for system_time (").append(systemPeriodStart).append(", ").append(systemPeriodEnd).append(")").endOfStatement();
 
-    apply.append("alter table ").append(baseTable).append("set (system_versioning = on)").endOfStatement();
+    String historyTable = baseTable + "_history"; // history must contain schema, otherwise you'll get
+    // Setting SYSTEM_VERSIONING to ON failed because history table 'xxx_history' is not specified in two-part name format.
+    if (historyTable.indexOf('.') == -1) {
+      historyTable = "dbo." +historyTable; // so add the default schema, if none was specified.
+    }
+    apply.append("alter table ").append(baseTable).append(" set (system_versioning = on (history_table=").append(historyTable).append("))").endOfStatement();
+    
+    DdlBuffer drop = writer.dropAll();
+    drop.append("IF OBJECT_ID('").append(baseTable).append("', 'U') IS NOT NULL alter table ").append(baseTable).append(" set (system_versioning = off)").endOfStatement();
+    drop.append("IF OBJECT_ID('").append(baseTable).append("_history', 'U') IS NOT NULL drop table ").append(baseTable).append("_history").endOfStatement();
   }
 
   @Override
   public void dropHistoryTable(DdlWrite writer, DropHistoryTable dropHistoryTable) throws IOException {
     String baseTable = dropHistoryTable.getBaseTable();
     DdlBuffer apply = writer.applyHistory();
-    apply.append("alter table ").append(baseTable).append("set (system_versioning = off)").endOfStatement();
+    apply.append("-- dropping history support for ").append(baseTable).endOfStatement();
+    // drop default constraints
+    
+    apply.append(platformDdl.alterColumnDefaultValue(baseTable, systemPeriodStart, DdlHelp.DROP_DEFAULT)).endOfStatement();
+    apply.append(platformDdl.alterColumnDefaultValue(baseTable, systemPeriodEnd, DdlHelp.DROP_DEFAULT)).endOfStatement();
+    // switch of versioning & period
+    apply.append("alter table ").append(baseTable).append(" set (system_versioning = off)").endOfStatement();
+    apply.append("alter table ").append(baseTable).append(" drop period for system_time").endOfStatement();
+    // now drop tables & columns
     apply.append("alter table ").append(baseTable).append(" drop column ").append(systemPeriodStart).endOfStatement();
     apply.append("alter table ").append(baseTable).append(" drop column ").append(systemPeriodEnd).endOfStatement();
+    apply.append("IF OBJECT_ID('").append(baseTable).append("_history', 'U') IS NOT NULL drop table ").append(baseTable).append("_history").endOfStatement();
+    apply.end();
   }
 
   @Override

src/main/java/io/ebean/dbmigration/migration/AlterColumn.java

@@ -1,8 +1,12 @@
 package io.ebean.dbmigration.migration;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 import javax.xml.bind.annotation.XmlAttribute;
+import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.XmlType;
 
@@ -44,10 +48,17 @@ import javax.xml.bind.annotation.XmlType;
  * </pre>
  */
 @XmlAccessorType(XmlAccessType.FIELD)
-@XmlType(name = "")
+@XmlType(name = "", propOrder = {
+    "before", "after"
+})
 @XmlRootElement(name = "alterColumn")
 public class AlterColumn {
 
+  @XmlElement(required = false)
+  protected List<DdlScript> before;
+  @XmlElement(required = false)
+  protected List<DdlScript> after;
+  
   @XmlAttribute(name = "columnName", required = true)
   protected String columnName;
   @XmlAttribute(name = "tableName", required = true)
@@ -533,4 +544,17 @@ public class AlterColumn {
     this.dropForeignKeyIndex = value;
   }
 
+  public List<DdlScript> getBefore() {
+    if (before == null) {
+      before = new ArrayList<>();
+    }
+    return before;
+  }
+  
+  public List<DdlScript> getAfter() {
+    if (after == null) {
+      after = new ArrayList<>();
+    }
+    return after;
+  }
 }

src/main/java/io/ebean/dbmigration/migration/Column.java

@@ -1,11 +1,14 @@
 package io.ebean.dbmigration.migration;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 import javax.xml.bind.annotation.XmlAttribute;
+import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.XmlType;
-import javax.xml.bind.annotation.XmlValue;
 
 
 /**
@@ -39,13 +42,16 @@ import javax.xml.bind.annotation.XmlValue;
  */
 @XmlAccessorType(XmlAccessType.FIELD)
 @XmlType(name = "", propOrder = {
-  "content"
+  "before", "after"
 })
 @XmlRootElement(name = "column")
 public class Column {
-
-  @XmlValue
-  protected String content;
+  
+  @XmlElement(required = false) 
+  protected List<DdlScript> before;
+  @XmlElement(required = false)
+  protected List<DdlScript> after;
+  
   @XmlAttribute(name = "name", required = true)
   protected String name;
   @XmlAttribute(name = "type", required = true)
@@ -76,27 +82,22 @@ public class Column {
   protected String foreignKeyIndex;
   @XmlAttribute(name = "comment")
   protected String comment;
+  
 
-  /**
-   * Gets the value of the content property.
-   *
-   * @return possible object is
-   * {@link String }
-   */
-  public String getContent() {
-    return content;
+  public List<DdlScript> getBefore() {
+    if (before == null) {
+      before = new ArrayList<>();
+    }
+    return before;
   }
-
-  /**
-   * Sets the value of the content property.
-   *
-   * @param value allowed object is
-   *              {@link String }
-   */
-  public void setContent(String value) {
-    this.content = value;
+  
+  public List<DdlScript> getAfter() {
+    if (after == null) {
+      after = new ArrayList<>();
+    }
+    return after;
   }
-
+  
   /**
    * Gets the value of the name property.
    *

src/main/java/io/ebean/dbmigration/migration/DdlScript.java

@@ -0,0 +1,73 @@
+package io.ebean.dbmigration.migration;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlAttribute;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+import javax.xml.bind.annotation.XmlValue;
+
+
+/**
+ * <p>Java class for anonymous complex type.
+ * <p>
+ * <p>The following schema fragment specifies the expected content contained within this class.
+ * <p>
+ * <pre>
+ * TODO @Rob: Can this generated automatically?
+ * </pre>
+ */
+@XmlAccessorType(XmlAccessType.FIELD)
+@XmlType(name = "", propOrder = {
+  "ddl"
+})
+@XmlRootElement(name = "ddl-script")
+public class DdlScript {
+
+  @XmlValue
+  protected List<String> ddl;
+
+  @XmlAttribute(name = "platforms")
+  protected String platforms;
+
+  /**
+   * Gets the value of the value property.
+   *
+   * @return possible object is
+   * {@link String }
+   */
+  public List<String> getDdl() {
+    if (ddl == null) {
+      ddl = new ArrayList<>();
+    }
+    return ddl;
+  }
+
+  public void setDdl(List<String> ddl) {
+    this.ddl = ddl;
+  }
+  
+  /**
+   * Gets the value of the platforms property.
+   *
+   * @return possible object is
+   * {@link String }
+   */
+  public String getPlatforms() {
+    return platforms;
+  }
+
+  /**
+   * Sets the value of the platforms property.
+   *
+   * @param value allowed object is
+   *              {@link String }
+   */
+  public void setPlatforms(String value) {
+    this.platforms = value;
+  }
+
+}

src/main/java/io/ebean/dbmigration/migration/DropTable.java

@@ -29,6 +29,10 @@ public class DropTable {
 
   @XmlAttribute(name = "name", required = true)
   protected String name;
+  @XmlAttribute(name = "sequenceCol")
+  protected String sequenceCol;
+  @XmlAttribute(name = "sequenceName")
+  protected String sequenceName;
 
   /**
    * Gets the value of the name property.
@@ -50,4 +54,44 @@ public class DropTable {
     this.name = value;
   }
 
+  /**
+   * Gets the value of the sequenceCol property.
+   *
+   * @return possible object is
+   * {@link String }
+   */
+  public String getSequenceCol() {
+    return sequenceCol;
+  }
+
+  /**
+   * Gets the value of the sequenceName property.
+   *
+   * @return possible object is
+   * {@link String }
+   */
+  public String getSequenceName() {
+    return sequenceName;
+  }
+
+  /**
+   * Sets the value of the sequenceCol property.
+   *
+   * @param value allowed object is
+   *              {@link String }
+   */
+  public void setSequenceCol(String value) {
+    this.sequenceCol = value;
+  }
+
+  /**
+   * Sets the value of the sequenceName property.
+   *
+   * @param value allowed object is
+   *              {@link String }
+   */
+  public void setSequenceName(String value) {
+    this.sequenceName = value;
+  }
+
 }

src/main/java/io/ebean/dbmigration/migration/ObjectFactory.java

@@ -186,5 +186,13 @@ public class ObjectFactory {
   public Migration createMigration() {
     return new Migration();
   }
+  
+  /**
+   * Create an instance of {@link DdlScript }
+   */
+  public DdlScript createDdlScript() {
+    return new DdlScript();
+  }
+  
 
 }

src/main/java/io/ebean/dbmigration/model/MColumn.java

@@ -1,7 +1,12 @@
 package io.ebean.dbmigration.model;
 
+import java.util.List;
+
+import io.ebean.dbmigration.ddlgeneration.platform.DdlHelp;
 import io.ebean.dbmigration.migration.AlterColumn;
 import io.ebean.dbmigration.migration.Column;
+import io.ebean.dbmigration.migration.DdlScript;
+import io.ebeaninternal.server.deploy.DbMigrationInfo;
 
 /**
  * A column in the logical model.
@@ -37,6 +42,8 @@ public class MColumn {
   private AlterColumn alterColumn;
 
   private boolean draftOnly;
+  
+  private List<DbMigrationInfo> dbMigrationInfos;
 
   public MColumn(Column column) {
     this.name = column.getName();
@@ -77,6 +84,7 @@ public class MColumn {
     copy.checkConstraint = checkConstraint;
     copy.checkConstraintName = checkConstraintName;
     copy.defaultValue = defaultValue;
+    copy.dbMigrationInfos = dbMigrationInfos;
     copy.references = references;
     copy.comment = comment;
     copy.foreignKeyName = foreignKeyName;
@@ -256,6 +264,24 @@ public class MColumn {
     c.setComment(comment);
     c.setUnique(unique);
     c.setUniqueOneToOne(uniqueOneToOne);
+    
+    if (dbMigrationInfos != null) {
+      for (DbMigrationInfo info : dbMigrationInfos) {
+        if (!info.getPreAdd().isEmpty()) {
+          DdlScript script = new DdlScript();
+          script.setDdl(info.getPreAdd());
+          script.setPlatforms(info.joinPlatforms());
+          c.getBefore().add(script);
+        }
+        
+        if (!info.getPostAdd().isEmpty()) {
+          DdlScript script = new DdlScript();
+          script.setDdl(info.getPostAdd());
+          script.setPlatforms(info.joinPlatforms());
+          c.getAfter().add(script);
+        }
+      }
+    }
 
     return c;
   }
@@ -280,6 +306,24 @@ public class MColumn {
       if (tableWithHistory) {
         alterColumn.setWithHistory(Boolean.TRUE);
       }
+      
+      if (dbMigrationInfos != null) {
+        for (DbMigrationInfo info : dbMigrationInfos) {
+          if (!info.getPreAlter().isEmpty()) {
+            DdlScript script = new DdlScript();
+            script.setDdl(info.getPreAlter());
+            script.setPlatforms(info.joinPlatforms());
+            alterColumn.getBefore().add(script);
+          }
+          
+          if (!info.getPostAlter().isEmpty()) {
+            DdlScript script = new DdlScript();
+            script.setDdl(info.getPostAlter());
+            script.setPlatforms(info.joinPlatforms());
+            alterColumn.getAfter().add(script);
+          }
+        }
+      }
     }
     return alterColumn;
   }
@@ -290,6 +334,8 @@ public class MColumn {
    */
   public void compare(ModelDiff modelDiff, MTable table, MColumn newColumn) {
 
+    this.dbMigrationInfos = newColumn.dbMigrationInfos;
+    
     boolean tableWithHistory = table.isWithHistory();
     String tableName = table.getName();
 
@@ -313,14 +359,18 @@ public class MColumn {
     if (different(defaultValue, newColumn.defaultValue)) {
       AlterColumn alter = getAlterColumn(tableName, tableWithHistory);
       if (newColumn.defaultValue == null) {
-        alter.setDefaultValue("DROP DEFAULT");
+        alter.setDefaultValue(DdlHelp.DROP_DEFAULT);
       } else {
         alter.setDefaultValue(newColumn.defaultValue);
       }
     }
     if (different(comment, newColumn.comment)) {
       AlterColumn alter = getAlterColumn(tableName, tableWithHistory);
-      alter.setComment(newColumn.comment);
+      if (newColumn.comment == null) {
+        alter.setComment(DdlHelp.DROP_COMMENT);
+      } else {
+        alter.setComment(newColumn.comment);
+      }
     }
     if (different(checkConstraint, newColumn.checkConstraint)) {
       AlterColumn alter = getAlterColumn(tableName, tableWithHistory);
@@ -378,6 +428,10 @@ public class MColumn {
     }
   }
 
+  public void setDbMigrationInfos(List<DbMigrationInfo> dbMigrationInfos) {
+    this.dbMigrationInfos = dbMigrationInfos;
+  }
+  
   /**
    * Apply changes based on the AlterColumn request.
    */
@@ -388,6 +442,7 @@ public class MColumn {
     }
     if (hasValue(alterColumn.getDropForeignKey())) {
       foreignKeyName = null;
+      references = null;
     }
     if (hasValue(alterColumn.getDropForeignKeyIndex())) {
       foreignKeyIndex = null;
@@ -405,6 +460,9 @@ public class MColumn {
     }
     if (hasValue(alterColumn.getDefaultValue())) {
       defaultValue = alterColumn.getDefaultValue();
+      if (DdlHelp.isDropDefault(defaultValue)) {
+        defaultValue = null;
+      }
     }
     if (hasValue(alterColumn.getCheckConstraint())) {
       checkConstraint = alterColumn.getCheckConstraint();
@@ -427,6 +485,12 @@ public class MColumn {
     if (hasValue(alterColumn.getForeignKeyIndex())) {
       foreignKeyIndex = alterColumn.getForeignKeyIndex();
     }
+    if (hasValue(alterColumn.getComment())) {
+      comment = alterColumn.getComment();
+      if (DdlHelp.isDropComment(comment)) {
+        comment = null;
+      }
+    }
 
   }
 }

src/main/java/io/ebean/dbmigration/model/MTable.java

@@ -1,5 +1,6 @@
 package io.ebean.dbmigration.model;
 
+import io.ebean.dbmigration.ddlgeneration.platform.DdlHelp;
 import io.ebean.dbmigration.migration.AddColumn;
 import io.ebean.dbmigration.migration.AddHistoryTable;
 import io.ebean.dbmigration.migration.AddTableComment;
@@ -180,6 +181,24 @@ public class MTable {
   public DropTable dropTable() {
     DropTable dropTable = new DropTable();
     dropTable.setName(name);
+    // we must add pk col name & sequence name, as we have to delete the sequence also.
+    if (identityType != IdentityType.GENERATOR && identityType != IdentityType.EXTERNAL) {
+      String pkCol = null;
+      for (MColumn column : columns.values()) {
+        if (column.isPrimaryKey()) {
+          if (pkCol == null) {
+            pkCol = column.getName();
+          } else { // multiple pk cols -> no sequence
+            pkCol = null;
+            break;
+          }
+        }
+      }
+      if (pkCol != null) {
+        dropTable.setSequenceCol(pkCol);
+        dropTable.setSequenceName(sequenceName);
+      }
+    }
     return dropTable;
   }
 
@@ -288,7 +307,11 @@ public class MTable {
     if (MColumn.different(comment, newTable.comment)) {
       AddTableComment addTableComment = new AddTableComment();
       addTableComment.setName(name);
-      addTableComment.setComment(newTable.comment);
+      if (newTable.comment == null) {
+        addTableComment.setComment(DdlHelp.DROP_COMMENT);
+      } else {
+        addTableComment.setComment(newTable.comment);
+      }
       modelDiff.addTableComment(addTableComment);
     }
   }
@@ -376,9 +399,7 @@ public class MTable {
       }
     }
     if (includeDropped && !droppedColumns.isEmpty()) {
-      for (String droppedColumn : droppedColumns) {
-        columnNames.add(droppedColumn);
-      }
+      columnNames.addAll(droppedColumns);
     }
     return columnNames;
   }

src/main/java/io/ebean/dbmigration/model/MigrationVersion.java

@@ -1,12 +1,15 @@
 package io.ebean.dbmigration.model;
 
 import java.util.Arrays;
+import java.util.regex.Pattern;
 
 /**
  * The version of a migration used so that migrations are processed in order.
  */
 public class MigrationVersion implements Comparable<MigrationVersion> {
 
+  private static final Pattern SECTION_SPLITTER = Pattern.compile("[\\.-]");
+
   private static final int[] REPEAT_ORDERING = {Integer.MAX_VALUE};
 
   private static final boolean[] REPEAT_UNDERSCORES = {false};
@@ -169,7 +172,7 @@ public class MigrationVersion implements Comparable<MigrationVersion> {
 
     value = value.replace('_', '.');
 
-    String[] sections = value.split("[\\.-]");
+    String[] sections = SECTION_SPLITTER.split(value);
 
     if ("r".equalsIgnoreCase(sections[0])) {
       // a "repeatable" version (does not have a version number)

src/main/java/io/ebean/dbmigration/model/ModelContainer.java

@@ -1,7 +1,9 @@
 package io.ebean.dbmigration.model;
 
+import io.ebean.dbmigration.ddlgeneration.platform.DdlHelp;
 import io.ebean.dbmigration.migration.AddColumn;
 import io.ebean.dbmigration.migration.AddHistoryTable;
+import io.ebean.dbmigration.migration.AddTableComment;
 import io.ebean.dbmigration.migration.AlterColumn;
 import io.ebean.dbmigration.migration.ChangeSet;
 import io.ebean.dbmigration.migration.ChangeSetType;
@@ -132,6 +134,10 @@ public class ModelContainer {
         applyChange((AddHistoryTable) change);
       } else if (change instanceof DropHistoryTable) {
         applyChange((DropHistoryTable) change);
+      } else if (change instanceof AddTableComment) {
+        applyChange((AddTableComment) change);          
+      } else {
+        throw new IllegalArgumentException("No rule for " + change);
       }
     }
   }
@@ -159,6 +165,18 @@ public class ModelContainer {
     }
     table.setWithHistory(false);
   }
+  
+  private void applyChange(AddTableComment change) {
+    MTable table = tables.get(change.getName());
+    if (table == null) {
+      throw new IllegalStateException("Table [" + change.getName() + "] does not exist in model?");
+    }
+    if (DdlHelp.isDropComment(change.getComment())) {
+      table.setComment(null);
+    } else {
+      table.setComment(change.getComment());
+    }
+  }
 
   /**
    * Apply a CreateTable change to the model.

src/main/java/io/ebean/dbmigration/model/PendingDrops.java

@@ -23,11 +23,7 @@ public class PendingDrops {
    */
   public void add(MigrationVersion version, ChangeSet changeSet) {
 
-    Entry entry = map.get(version.normalised());
-    if (entry == null) {
-      entry = new Entry(version);
-      map.put(version.normalised(), entry);
-    }
+    Entry entry = map.computeIfAbsent(version.normalised(), k -> new Entry(version));
     entry.add(changeSet);
   }
 

src/main/java/io/ebean/dbmigration/model/PlatformDdlWriter.java

@@ -29,14 +29,11 @@ public class PlatformDdlWriter {
 
   private final DatabasePlatform platform;
 
-  private final String platformPrefix;
-
   private final DbMigrationConfig config;
 
-  public PlatformDdlWriter(DatabasePlatform platform, ServerConfig serverConfig, String platformPrefix, DbMigrationConfig config) {
+  public PlatformDdlWriter(DatabasePlatform platform, ServerConfig serverConfig, DbMigrationConfig config) {
     this.platform = platform;
     this.serverConfig = serverConfig;
-    this.platformPrefix = platformPrefix;
     this.config = config;
   }
 

src/main/java/io/ebean/dbmigration/model/build/ModelBuildBeanVisitor.java

@@ -53,10 +53,12 @@ public class ModelBuildBeanVisitor implements BeanVisitor {
     if (inheritInfo != null && inheritInfo.isRoot()) {
       // add the discriminator column
       String discColumn = inheritInfo.getDiscriminatorColumn();
-      DbPlatformType dbType = ctx.getDbTypeMap().get(inheritInfo.getDiscriminatorType());
-      String discDbType = dbType.renderType(inheritInfo.getDiscriminatorLength(), 0);
-
-      table.addColumn(new MColumn(discColumn, discDbType, true));
+      String columnDefn = inheritInfo.getColumnDefn();
+      if (columnDefn == null || columnDefn.isEmpty()) {
+        DbPlatformType dbType = ctx.getDbTypeMap().get(inheritInfo.getDiscriminatorType());
+        columnDefn = dbType.renderType(inheritInfo.getColumnLength(), 0);
+      }
+      table.addColumn(new MColumn(discColumn, columnDefn, true));
     }
 
     return new ModelBuildPropertyVisitor(ctx, table, descriptor);

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

@@ -177,7 +177,8 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
       String refColumn = importedProperty.getDbColumn();
 
       MColumn col = table.addColumn(dbCol, columnDefn, !p.isNullable());
-
+      col.setDbMigrationInfos(p.getDbMigrationInfos());
+      col.setDefaultValue(p.getDbColumnDefault());
       if (columns.length == 1) {
         // single references column (put it on the column)
         String refTable = importedProperty.getBeanDescriptor().getBaseTable();
@@ -221,7 +222,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
     // using non-strict mode to render the DB type such that we have a
     // "logical" type like jsonb(200) that can map to JSONB or VARCHAR(200)
     MColumn col = new MColumn(p.getDbColumn(), ctx.getColumnDefn(p, false));
-    col.setDefaultValue(p.getDbColumnDefault());
     col.setComment(p.getDbComment());
     col.setDraftOnly(p.isDraftOnly());
     col.setHistoryExclude(p.isExcludedFromHistory());
@@ -231,8 +231,12 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
       if (p.getBeanDescriptor().isUseIdGenerator()) {
         col.setIdentity(true);
       }
-    } else if (!p.isNullable() || p.isDDLNotNull()) {
-      col.setNotnull(true);
+    } else {
+      col.setDefaultValue(p.getDbColumnDefault());
+      col.setDbMigrationInfos(p.getDbMigrationInfos());
+      if (!p.isNullable() || p.isDDLNotNull()) {
+        col.setNotnull(true);
+      }
     }
 
     if (p.isUnique() && !p.isId()) {

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

@@ -127,7 +127,7 @@ public class VisitAllUsing {
    * Helper used to visit all the inheritInfo/BeanDescriptor in
    * the inheritance hierarchy (to add their 'local' properties).
    */
-  protected class InheritChildVisitor implements InheritInfoVisitor {
+  protected static class InheritChildVisitor implements InheritInfoVisitor {
 
     private final VisitAllUsing owner;
     private final BeanPropertyVisitor pv;

src/main/java/io/ebean/overview.html

@@ -35,7 +35,7 @@ Customer customer = Ebean.find(Customer.class)
     .fetch("billingAddress");
     .fetch("shippingAddress");
     .setId(7)
-    .findUnique();
+    .findOne();
 
 
 Address billAddr = customer.getBillingAddress();

src/main/java/io/ebean/package.html

@@ -28,7 +28,7 @@ Customer customer =
 		.setId(7)
 		.fetch("billingAddress")
 		.fetch("shippingAddress")
-		.findUnique();
+		.findOne();
 
 Address billAddr = customer.getBillingAddress();
 Address shipAddr = customer.getShippingAddress();

src/main/java/io/ebean/text/PathProperties.java

@@ -89,11 +89,7 @@ public class PathProperties implements FetchPath {
   }
 
   Props getProps(String path) {
-    Props props = pathMap.get(path);
-    if (props == null) {
-      props = new Props(this, null, path);
-      pathMap.put(path, props);
-    }
+    Props props = pathMap.computeIfAbsent(path, p -> new Props(this, null, p));
     return props;
   }
 

src/main/java/io/ebean/text/TimeStringParser.java

@@ -27,16 +27,17 @@ public final class TimeStringParser implements StringParser {
     }
 
     String s = value.trim();
-    int minute;
-    int second;
     int firstColon = s.indexOf(':');
-    int secondColon = s.indexOf(':', firstColon + 1);
 
     if (firstColon == -1) {
       throw new java.lang.IllegalArgumentException("No ':' in value [" + s + "]");
     }
     try {
+      int second;
+      int minute;
       int hour = Integer.parseInt(s.substring(0, firstColon));
+      int secondColon = s.indexOf(':', firstColon + 1);
+
       if (secondColon == -1) {
         minute = Integer.parseInt(s.substring(firstColon + 1, s.length()));
         second = 0;

src/main/java/io/ebean/text/json/EJson.java

@@ -158,7 +158,12 @@ public class EJson {
     if (list == null) {
       return null;
     }
-    return ((ModifyAwareList) list).asSet();
+
+    if (modifyAware) {
+      return ((ModifyAwareList) list).asSet();
+    } else {
+      return new LinkedHashSet<>(list);
+    }
   }
 
   /**

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

@@ -12,7 +12,7 @@ public class CamelCaseHelper {
 
     String[] vals = underscore.split("_");
     if (vals.length == 1) {
-      return underscore;
+      return isUpperCase(underscore) ? underscore.toLowerCase() : underscore;
     }
 
     StringBuilder result = new StringBuilder();
@@ -29,4 +29,13 @@ public class CamelCaseHelper {
 
     return result.toString();
   }
+
+  private static boolean isUpperCase(String underscore) {
+    for (int i = 0; i < underscore.length(); i++) {
+      if (Character.isLowerCase(underscore.charAt(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
 }

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

@@ -3,6 +3,7 @@ package io.ebean.util;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.regex.Pattern;
 
 /**
  * Utility String class that supports String manipulation functions.
@@ -12,6 +13,10 @@ public class StringHelper {
   private static final char SINGLE_QUOTE = '\'';
 
   private static final char DOUBLE_QUOTE = '"';
+  
+  private static final Pattern SPLIT_NAMES = Pattern.compile("[\\s,;]+");
+  
+  private static final String[] EMPTY_STRING_ARRAY = new String[0];
 
   /**
    * parses a String of the form name1='value1' name2='value2'. Note that you
@@ -48,42 +53,44 @@ public class StringHelper {
    */
   private static HashMap<String, String> parseNameQuotedValue(HashMap<String, String> map,
                                                               String tag, int pos) throws RuntimeException {
+    while (true) {
 
-    int equalsPos = tag.indexOf('=', pos);
-    if (equalsPos > -1) {
-      // check for begin quote...
-      char firstQuote = tag.charAt(equalsPos + 1);
-      if (firstQuote != SINGLE_QUOTE && firstQuote != DOUBLE_QUOTE) {
-        throw new RuntimeException("missing begin quote at " + (equalsPos) + "["
-          + tag.charAt(equalsPos + 1) + "] in [" + tag + "]");
+      int equalsPos = tag.indexOf('=', pos);
+      if (equalsPos > -1) {
+        // check for begin quote...
+        char firstQuote = tag.charAt(equalsPos + 1);
+        if (firstQuote != SINGLE_QUOTE && firstQuote != DOUBLE_QUOTE) {
+          throw new RuntimeException("missing begin quote at " + (equalsPos) + "["
+            + tag.charAt(equalsPos + 1) + "] in [" + tag + "]");
+        }
+
+        // check for end quote...
+        int endQuotePos = tag.indexOf(firstQuote, equalsPos + 2);
+        if (endQuotePos == -1) {
+          throw new RuntimeException("missing end quote [" + firstQuote + "] after " + pos + " in [" + tag + "]");
+        }
+
+        // we have a valid name and value...
+        // dp("pos="+pos+" equalsPos="+equalsPos+"
+        // endQuotePos="+endQuotePos);
+        String name = tag.substring(pos, equalsPos);
+        // dp("name="+name+"; value="+value+";");
+
+        // trim off any whitespace from the front of name...
+        name = trimFront(name, " ");
+        if ((name.indexOf(SINGLE_QUOTE) > -1) || (name.indexOf(DOUBLE_QUOTE) > -1)) {
+          throw new RuntimeException("attribute name contains a quote [" + name + "]");
+        }
+
+        String value = tag.substring(equalsPos + 2, endQuotePos);
+        map.put(name, value);
+
+        pos = endQuotePos + 1;
+
+      } else {
+        // no more equals... stop parsing...
+        return map;
       }
-
-      // check for end quote...
-      int endQuotePos = tag.indexOf(firstQuote, equalsPos + 2);
-      if (endQuotePos == -1) {
-        throw new RuntimeException("missing end quote [" + firstQuote + "] after " + pos + " in [" + tag + "]");
-      }
-
-      // we have a valid name and value...
-      // dp("pos="+pos+" equalsPos="+equalsPos+"
-      // endQuotePos="+endQuotePos);
-      String name = tag.substring(pos, equalsPos);
-      // dp("name="+name+"; value="+value+";");
-
-      // trim off any whitespace from the front of name...
-      name = trimFront(name, " ");
-      if ((name.indexOf(SINGLE_QUOTE) > -1) || (name.indexOf(DOUBLE_QUOTE) > -1)) {
-        throw new RuntimeException("attribute name contains a quote [" + name + "]");
-      }
-
-      String value = tag.substring(equalsPos + 2, endQuotePos);
-      map.put(name, value);
-
-      return parseNameQuotedValue(map, tag, endQuotePos + 1);
-
-    } else {
-      // no more equals... stop parsing...
-      return map;
     }
   }
 
@@ -96,14 +103,15 @@ public class StringHelper {
   }
 
   private static int countOccurances(String content, String occurs, int pos, int countSoFar) {
-    int equalsPos = content.indexOf(occurs, pos);
-    if (equalsPos > -1) {
-      countSoFar += 1;
-      pos = equalsPos + occurs.length();
-      // dp("countSoFar="+countSoFar+" pos="+pos);
-      return countOccurances(content, occurs, pos, countSoFar);
-    } else {
-      return countSoFar;
+    while (true) {
+      int equalsPos = content.indexOf(occurs, pos);
+      if (equalsPos > -1) {
+        countSoFar += 1;
+        pos = equalsPos + occurs.length();
+        // dp("countSoFar="+countSoFar+" pos="+pos);
+      } else {
+        return countSoFar;
+      }
     }
   }
 
@@ -135,14 +143,16 @@ public class StringHelper {
    * @param trim   the string to trim off the front
    */
   public static String trimFront(String source, String trim) {
-    if (source == null) {
-      return null;
-    }
-    if (source.indexOf(trim) == 0) {
-      // dp("trim ...");
-      return trimFront(source.substring(trim.length()), trim);
-    } else {
-      return source;
+    while (true) {
+      if (source == null) {
+        return null;
+      }
+      if (source.indexOf(trim) == 0) {
+        // dp("trim ...");
+        source = source.substring(trim.length());
+      } else {
+        return source;
+      }
     }
   }
 
@@ -158,55 +168,57 @@ public class StringHelper {
    */
   private static HashMap<String, String> getKeyValue(HashMap<String, String> map, int pos,
                                                      String allNameValuePairs, String listDelimiter, String nameValueSeparator) {
+    while (true) {
 
-    if (pos >= allNameValuePairs.length()) {
-      // dp("end as "+pos+" >= "+allNameValuePairs.length() );
-      return map;
-    }
-
-    int equalsPos = allNameValuePairs.indexOf(nameValueSeparator, pos);
-    int delimPos = allNameValuePairs.indexOf(listDelimiter, pos);
-
-    if (delimPos == -1) {
-      delimPos = allNameValuePairs.length();
-    }
-    if (equalsPos == -1) {
-      // dp("no more equals...");
-      return map;
-    }
-    if (delimPos == (equalsPos + 1)) {
-      // dp("Ignoring as nothing between delim and equals...
-      // delim:"+delimPos+" eq:"+equalsPos);
-      return getKeyValue(map, delimPos + 1, allNameValuePairs, listDelimiter,
-        nameValueSeparator);
-    }
-    if (equalsPos > delimPos) {
-      // there is a key without a value?
-      String key = allNameValuePairs.substring(pos, delimPos);
-      key = key.trim();
-      if (!key.isEmpty()) {
-        map.put(key, null);
+      if (pos >= allNameValuePairs.length()) {
+        // dp("end as "+pos+" >= "+allNameValuePairs.length() );
+        return map;
       }
-      return getKeyValue(map, delimPos + 1, allNameValuePairs, listDelimiter,
-        nameValueSeparator);
 
-    }
-    String key = allNameValuePairs.substring(pos, equalsPos);
+      int equalsPos = allNameValuePairs.indexOf(nameValueSeparator, pos);
+      int delimPos = allNameValuePairs.indexOf(listDelimiter, pos);
 
-    if (delimPos > -1) {
-      String value = allNameValuePairs.substring(equalsPos + 1, delimPos);
-      // dp("cont "+key+","+value+" pos:"+pos+"
-      // len:"+allNameValuePairs.length());
-      key = key.trim();
+      if (delimPos == -1) {
+        delimPos = allNameValuePairs.length();
+      }
+      if (equalsPos == -1) {
+        // dp("no more equals...");
+        return map;
+      }
+      if (delimPos == (equalsPos + 1)) {
+        // dp("Ignoring as nothing between delim and equals...
+        // delim:"+delimPos+" eq:"+equalsPos);
+        pos = delimPos + 1;
+        continue;
+      }
+      if (equalsPos > delimPos) {
+        // there is a key without a value?
+        String key = allNameValuePairs.substring(pos, delimPos);
+        key = key.trim();
+        if (!key.isEmpty()) {
+          map.put(key, null);
+        }
+        pos = delimPos + 1;
+        continue;
 
-      map.put(key, value);
-      pos = delimPos + 1;
+      }
+      String key = allNameValuePairs.substring(pos, equalsPos);
 
-      // recurse the rest of the values...
-      return getKeyValue(map, pos, allNameValuePairs, listDelimiter, nameValueSeparator);
-    } else {
-      // dp("ERROR: delimPos < 0 ???");
-      return map;
+      if (delimPos > -1) {
+        String value = allNameValuePairs.substring(equalsPos + 1, delimPos);
+        // dp("cont "+key+","+value+" pos:"+pos+"
+        // len:"+allNameValuePairs.length());
+        key = key.trim();
+
+        map.put(key, value);
+        pos = delimPos + 1;
+
+        // recurse the rest of the values...
+
+      } else {
+        // dp("ERROR: delimPos < 0 ???");
+        return map;
+      }
     }
   }
 
@@ -423,6 +435,9 @@ public class StringHelper {
    * }</pre>
    */
   public static String replaceStringMulti(String source, String[] match, String replace) {
+    if (source == null) {
+      return null;
+    }
     return replaceStringMulti(source, match, replace, 30, 0, source.length());
   }
 
@@ -436,7 +451,9 @@ public class StringHelper {
    */
   public static String replaceStringMulti(String source, String[] match, String replace,
                                           int additionalSize, int startPos, int endPos) {
-
+    if (source == null) {
+      return null;
+    }
     int shortestMatch = match[0].length();
 
     char[] match0 = new char[match.length];
@@ -540,4 +557,28 @@ public class StringHelper {
     return false;
   }
 
+  /**
+   * Splits at any whitespace "," or ";" and trims the result.
+   * It does not return empty entries.
+   */
+  public static String[] splitNames(String names) {
+    if (names == null || names.isEmpty()) {
+      return EMPTY_STRING_ARRAY;
+    }
+    String[] result = SPLIT_NAMES.split(names);
+    if (result.length == 0) {
+      return EMPTY_STRING_ARRAY; // don't know if this ever can happen
+    }
+    if ("".equals(result[0])) { //  = input string starts with whitespace
+      if (result.length == 1) { //  = input string contains only whitespace
+        return EMPTY_STRING_ARRAY;
+      } else {
+        String ret[] = new String[result.length-1]; // remove first entry
+        System.arraycopy(result, 1, ret, 0, ret.length);
+        return ret;
+      }
+    } else {
+      return result;
+    }
+  }
 }

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

@@ -35,7 +35,7 @@ public class BindParams implements Serializable {
    * Bind hash and count used to detect when the bind values have changed such
    * that the generated SQL (with named parameters) needs to be recalculated.
    */
-  private int[] bindHash;
+  private String bindHash;
 
   public BindParams() {
   }
@@ -56,32 +56,29 @@ public class BindParams implements Serializable {
    * taken into account when calculating the query hash.
    * </p>
    */
-  public void buildQueryPlanHash(HashQueryPlanBuilder builder) {
-    int[] vals = calcQueryPlanHash();
-    builder.add(vals[0]).bind(vals[1]);
+  public String calcQueryPlanHash() {
+    StringBuilder builder = new StringBuilder();
+    buildQueryPlanHash(builder);
+    return builder.toString();
   }
 
   /**
    * Calculate and return a query plan bind hash with total bind count.
    */
-  public int[] calcQueryPlanHash() {
+  public void buildQueryPlanHash(StringBuilder builder) {
     int tempBindCount;
     int bc = 0;
-    int hc = 92821;
     for (Param param : positionedParameters) {
       tempBindCount = param.queryBindCount();
       bc += tempBindCount;
-      hc = hc * 92821 + tempBindCount;
+      builder.append("p").append(bc).append(" ?:").append(tempBindCount).append(",");
     }
 
     for (Map.Entry<String, Param> entry : namedParameters.entrySet()) {
       tempBindCount = entry.getValue().queryBindCount();
       bc += tempBindCount;
-      hc = hc * 92821 + entry.getKey().hashCode();
-      hc = hc * 92821 + tempBindCount;
+      builder.append("n").append(bc).append(" k:").append(entry.getKey()).append(" ?:").append(tempBindCount).append(",");
     }
-
-    return new int[]{hc, bc};
   }
 
   /**
@@ -169,11 +166,7 @@ public class BindParams implements Serializable {
   }
 
   private Param getParam(String name) {
-    Param p = namedParameters.get(name);
-    if (p == null) {
-      p = new Param();
-      namedParameters.put(name, p);
-    }
+    Param p = namedParameters.computeIfAbsent(name, k -> new Param());
     return p;
   }
 
@@ -281,9 +274,9 @@ public class BindParams implements Serializable {
       bindHash = calcQueryPlanHash();
       return false;
     }
-    int[] oldPlan = bindHash;
+    String oldPlan = bindHash;
     bindHash = calcQueryPlanHash();
-    return bindHash[0] == oldPlan[0] && bindHash[1] == oldPlan[1];
+    return bindHash.equals(oldPlan);
   }
 
   /**

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

@@ -13,7 +13,6 @@ import io.ebeaninternal.server.persist.BatchControl;
 import io.ebeanservice.docstore.api.DocStoreTransaction;
 
 import javax.persistence.PersistenceException;
-import java.io.IOException;
 import java.sql.Connection;
 import java.sql.SQLException;
 

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

@@ -48,18 +48,13 @@ public interface SpiExpression extends Expression {
    * from an AutoTune perspective and get different tuning.
    * </p>
    */
-  void queryPlanHash(HashQueryPlanBuilder builder);
+  void queryPlanHash(StringBuilder builder);
 
   /**
    * Return the hash value for the values that will be bound.
    */
   int queryBindHash();
 
-  /**
-   * Return true if the expression is the same without taking into account bind values.
-   */
-  boolean isSameByPlan(SpiExpression other);
-
   /**
    * Return true if the expression is the same with respect to bind values.
    */

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

@@ -65,4 +65,9 @@ public interface SpiExpressionRequest {
    * Append a DB Like clause.
    */
   void appendLike();
+
+  /**
+   * Escapes a string to use it as exact match in Like clause.
+   */
+  String escapeLikeString(String value);
 }

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

@@ -161,6 +161,7 @@ public interface SpiQuery<T> extends Query<T> {
   /**
    * Return the ForUpdate mode.
    */
+  @Override
   ForUpdate getForUpdateMode();
 
   /**

src/main/java/io/ebeaninternal/extraddl/model/ExtraDdlXmlReader.java

@@ -1,8 +1,11 @@
 package io.ebeaninternal.extraddl.model;
 
+import java.util.regex.Pattern;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import io.ebean.util.StringHelper;
+
 import javax.xml.bind.JAXBContext;
 import javax.xml.bind.JAXBException;
 import javax.xml.bind.Unmarshaller;
@@ -44,9 +47,9 @@ public class ExtraDdlXmlReader {
     if (platforms == null || platforms.trim().isEmpty()) {
       return true;
     }
-    String[] names = platforms.split("[,;]");
-    for (String name : names) {
-      if (name.trim().toLowerCase().contains(platformName)) {
+
+    for (String name : StringHelper.splitNames(platforms)) {
+      if (name.toLowerCase().contains(platformName)) {
         return true;
       }
     }

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

@@ -103,11 +103,7 @@ public class ProfileManager implements ProfilingListener {
 
   private ProfileOrigin getProfileOrigin(ObjectGraphOrigin originQueryPoint) {
     synchronized (monitor) {
-      ProfileOrigin stats = profileMap.get(originQueryPoint.getKey());
-      if (stats == null) {
-        stats = new ProfileOrigin(originQueryPoint, queryTuningAddVersion, profilingBase, profilingRate);
-        profileMap.put(originQueryPoint.getKey(), stats);
-      }
+      ProfileOrigin stats = profileMap.computeIfAbsent(originQueryPoint.getKey(), k -> new ProfileOrigin(originQueryPoint, queryTuningAddVersion, profilingBase, profilingRate));
       return stats;
     }
   }

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

@@ -6,7 +6,6 @@ import io.ebeaninternal.server.autotune.model.ProfileDiff;
 import io.ebeaninternal.server.autotune.model.ProfileEmpty;
 import io.ebeaninternal.server.autotune.model.ProfileNew;
 
-import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 
@@ -23,19 +22,19 @@ public class SortAutoTuneDocument {
 
     ProfileDiff profileDiff = document.getProfileDiff();
     if (profileDiff != null) {
-      Collections.sort(profileDiff.getOrigin(), NAME_KEY_SORT);
+      profileDiff.getOrigin().sort(NAME_KEY_SORT);
     }
     ProfileNew profileNew = document.getProfileNew();
     if (profileNew != null) {
-      Collections.sort(profileNew.getOrigin(), NAME_KEY_SORT);
+      profileNew.getOrigin().sort(NAME_KEY_SORT);
     }
     ProfileEmpty profileEmpty = document.getProfileEmpty();
     if (profileEmpty != null) {
-      Collections.sort(profileEmpty.getOrigin(), KEY_SORT);
+      profileEmpty.getOrigin().sort(KEY_SORT);
     }
     List<Origin> origins = document.getOrigin();
     if (!origins.isEmpty()) {
-      Collections.sort(origins, NAME_KEY_SORT);
+      origins.sort(NAME_KEY_SORT);
     }
   }
 

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

@@ -122,11 +122,7 @@ public class CacheChangeSet {
    */
   private ManyChange many(BeanDescriptor<?> desc, String manyProperty) {
     ManyKey key = new ManyKey(desc, manyProperty);
-    ManyChange manyChange = manyChangeMap.get(key);
-    if (manyChange == null) {
-      manyChange = new ManyChange(key);
-      manyChangeMap.put(key, manyChange);
-    }
+    ManyChange manyChange = manyChangeMap.computeIfAbsent(key, ManyChange::new);
     return manyChange;
   }
 

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

@@ -24,28 +24,28 @@ public class DefaultCacheAdapter implements ServerCacheManager {
 
   @Override
   public ServerCache getNaturalKeyCache(Class<?> beanType) {
-    return cacheManager.getNaturalKeyCache(beanType).get();
+    return cacheManager.getNaturalKeyCache(beanType);
   }
 
   @Override
   public ServerCache getBeanCache(Class<?> beanType) {
-    return cacheManager.getBeanCache(beanType).get();
+    return cacheManager.getBeanCache(beanType);
   }
 
   @Override
   public ServerCache getCollectionIdsCache(Class<?> beanType, String propertyName) {
-    return cacheManager.getCollectionIdsCache(beanType, propertyName).get();
+    return cacheManager.getCollectionIdsCache(beanType, propertyName);
   }
 
   @Override
   public ServerCache getQueryCache(Class<?> beanType) {
-    return cacheManager.getQueryCache(beanType).get();
+    return cacheManager.getQueryCache(beanType);
   }
 
   @Override
   public void clear(Class<?> beanType) {
-    cacheManager.getBeanCache(beanType).get().clear();
-    cacheManager.getQueryCache(beanType).get().clear();
+    cacheManager.getBeanCache(beanType).clear();
+    cacheManager.getQueryCache(beanType).clear();
   }
 
   @Override

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

@@ -7,9 +7,9 @@ import io.ebean.cache.ServerCacheFactory;
 import io.ebean.cache.ServerCacheOptions;
 import io.ebean.cache.ServerCacheType;
 import io.ebean.config.CurrentTenantProvider;
+import io.ebeaninternal.server.deploy.parse.AnnotationBase;
 
 import java.util.concurrent.ConcurrentHashMap;
-import java.util.function.Supplier;
 
 /**
  * Manages the construction of caches.
@@ -39,12 +39,10 @@ class DefaultCacheHolder {
     this.tenantProvider = tenantProvider;
   }
 
-  Supplier<ServerCache> getCache(Class<?> beanType, String cacheKey, ServerCacheType type) {
+  ServerCache getCache(Class<?> beanType, String cacheKey, ServerCacheType type) {
+
+    return getCacheInternal(beanType, cacheKey, type);
 
-    if (tenantProvider == null) {
-      return new SimpleSupplier(getCacheInternal(beanType, cacheKey, type));
-    }
-    return new TenantSupplier(beanType, cacheKey, type);
   }
 
   private String key(String cacheKey, ServerCacheType type) {
@@ -62,7 +60,8 @@ class DefaultCacheHolder {
 
   private ServerCache createCache(Class<?> beanType, ServerCacheType type, String key) {
     ServerCacheOptions options = getCacheOptions(beanType, type);
-    return cacheFactory.createCache(type, key, options);
+    
+    return cacheFactory.createCache(type, key, tenantProvider, options);
   }
 
   void clearAll() {
@@ -84,7 +83,7 @@ class DefaultCacheHolder {
   }
 
   private ServerCacheOptions getQueryOptions(Class<?> cls) {
-    CacheQueryTuning tuning = cls.getAnnotation(CacheQueryTuning.class);
+    CacheQueryTuning tuning = AnnotationBase.findAnnotation(cls, CacheQueryTuning.class);
     if (tuning != null) {
       return new ServerCacheOptions(tuning).applyDefaults(queryDefault);
     }
@@ -99,40 +98,4 @@ class DefaultCacheHolder {
     return beanDefault.copy();
   }
 
-  /**
-   * Multi-Tenant based cache supplier.
-   */
-  private class TenantSupplier implements Supplier<ServerCache> {
-
-    final Class<?> beanType;
-    final String key;
-    final ServerCacheType type;
-
-    private TenantSupplier(Class<?> beanType, String key, ServerCacheType type) {
-      this.beanType = beanType;
-      this.key = key;
-      this.type = type;
-    }
-
-    @Override
-    public ServerCache get() {
-      String fullKey = key + "_" + tenantProvider.currentId();
-      return getCacheInternal(beanType, fullKey, type);
-    }
-  }
-
-  private static class SimpleSupplier implements Supplier<ServerCache> {
-
-    final ServerCache underlying;
-
-    private SimpleSupplier(ServerCache underlying) {
-      this.underlying = underlying;
-    }
-
-    @Override
-    public ServerCache get() {
-      return underlying;
-    }
-  }
-
 }

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

@@ -4,12 +4,15 @@ import io.ebean.BackgroundExecutor;
 import io.ebean.cache.ServerCache;
 import io.ebean.cache.ServerCacheOptions;
 import io.ebean.cache.ServerCacheStatistics;
+import io.ebean.cache.TenantAwareKey;
+import io.ebean.config.CurrentTenantProvider;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.Serializable;
+import java.util.List;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.Map;
@@ -51,8 +54,6 @@ public class DefaultServerCache implements ServerCache {
   protected final LongAdder evictCount = new LongAdder();
   protected final LongAdder evictMicros = new LongAdder();
 
-  protected final Object monitor = new Object();
-
   protected final String name;
 
   protected int maxSize;
@@ -63,27 +64,30 @@ public class DefaultServerCache implements ServerCache {
 
   protected int maxSecsToLive;
 
+  protected TenantAwareKey tenantAwareKey;
+
   /**
    * Construct using a ConcurrentHashMap and cache options.
    */
-  public DefaultServerCache(String name, ServerCacheOptions options) {
-    this(name, new ConcurrentHashMap<>(), options);
+  public DefaultServerCache(String name, CurrentTenantProvider tenantProvider, ServerCacheOptions options) {
+    this(name, new ConcurrentHashMap<>(), tenantProvider, options);
   }
 
   /**
    * Construct passing in name, map and base eviction controls as ServerCacheOptions.
    */
-  public DefaultServerCache(String name, Map<Object, CacheEntry> map, ServerCacheOptions options) {
-    this(name, map, options.getMaxSize(), options.getMaxIdleSecs(), options.getMaxSecsToLive(), options.getTrimFrequency());
+  public DefaultServerCache(String name, Map<Object, CacheEntry> map, CurrentTenantProvider tenantProvider, ServerCacheOptions options) {
+    this(name, map, tenantProvider, options.getMaxSize(), options.getMaxIdleSecs(), options.getMaxSecsToLive(), options.getTrimFrequency());
   }
 
   /**
    * Construct passing in name, map and base eviction controls.
    */
-  public DefaultServerCache(String name, Map<Object, CacheEntry> map, int maxSize, int maxIdleSecs, int maxSecsToLive, int trimFrequency) {
+  public DefaultServerCache(String name, Map<Object, CacheEntry> map, CurrentTenantProvider tenantProvider, int maxSize, int maxIdleSecs, int maxSecsToLive, int trimFrequency) {
     this.name = name;
     this.map = map;
     this.maxSize = maxSize;
+    this.tenantAwareKey = new TenantAwareKey(tenantProvider);
     this.maxIdleSecs = maxIdleSecs;
     this.maxSecsToLive = maxSecsToLive;
     this.trimFrequency = determineTrim(maxIdleSecs, maxSecsToLive, trimFrequency);
@@ -187,13 +191,20 @@ public class DefaultServerCache implements ServerCache {
     map.clear();
   }
 
+  /**
+   * Return the tenant aware key.
+   */
+  private Object key(Object id) {
+    return tenantAwareKey.key(id);
+  }
+
   /**
    * Return a value from the cache.
    */
   @Override
-  public Object get(Object key) {
+  public Object get(Object id) {
 
-    CacheEntry entry = map.get(key);
+    CacheEntry entry = map.get(key(id));
     if (entry == null) {
       missCount.increment();
       return null;
@@ -210,7 +221,9 @@ public class DefaultServerCache implements ServerCache {
    * Put a value into the cache.
    */
   @Override
-  public Object put(Object key, Object value) {
+  public Object put(Object id, Object value) {
+
+    Object key = key(id);
     CacheEntry entry = map.put(key, new CacheEntry(key, value));
     if (entry == null) {
       insertCount.increment();
@@ -225,8 +238,9 @@ public class DefaultServerCache implements ServerCache {
    * Remove an entry from the cache.
    */
   @Override
-  public Object remove(Object key) {
-    CacheEntry entry = map.remove(key);
+  public Object remove(Object id) {
+
+    CacheEntry entry = map.remove(key(id));
     if (entry == null) {
       return null;
     } else {
@@ -276,19 +290,19 @@ public class DefaultServerCache implements ServerCache {
     long trimmedByTTL = 0;
     long trimmedByLRU = 0;
 
-    ArrayList<CacheEntry> activeList = new ArrayList<>(map.size());
+    List<CacheEntry> activeList = new ArrayList<>(map.size());
 
-    long idleExpire = System.currentTimeMillis() - (maxIdleSecs * 1000);
-    long ttlExpire = System.currentTimeMillis() - (maxSecsToLive * 1000);
+    long idleExpireNano =  startNanos - TimeUnit.SECONDS.toNanos(maxIdleSecs);
+    long ttlExpireNano = startNanos - TimeUnit.SECONDS.toNanos(maxSecsToLive);
 
     Iterator<CacheEntry> it = map.values().iterator();
     while (it.hasNext()) {
       CacheEntry cacheEntry = it.next();
-      if (maxIdleSecs > 0 && idleExpire > cacheEntry.getLastAccessTime()) {
+      if (maxIdleSecs > 0 && idleExpireNano > cacheEntry.getLastAccessTime()) {
         it.remove();
         trimmedByIdle++;
 
-      } else if (maxSecsToLive > 0 && ttlExpire > cacheEntry.getCreateTime()) {
+      } else if (maxSecsToLive > 0 && ttlExpireNano > cacheEntry.getCreateTime()) {
         it.remove();
         trimmedByTTL++;
 
@@ -301,7 +315,7 @@ public class DefaultServerCache implements ServerCache {
       trimmedByLRU = activeList.size() - maxSize;
       if (trimmedByLRU > 0) {
         // sort into last access time ascending
-        Collections.sort(activeList, BY_LAST_ACCESS);
+        activeList.sort(BY_LAST_ACCESS);
         int trimSize = getTrimSize();
         for (int i = trimSize; i < activeList.size(); i++) {
           // remove if still in the cache
@@ -365,7 +379,7 @@ public class DefaultServerCache implements ServerCache {
     public CacheEntry(Object key, Object value) {
       this.key = key;
       this.value = value;
-      this.createTime = System.currentTimeMillis();
+      this.createTime = System.nanoTime();
       this.lastAccessTime = createTime;
     }
 
@@ -381,7 +395,7 @@ public class DefaultServerCache implements ServerCache {
      */
     public Object getValue() {
       // long assignment should be atomic these days (Ref Cliff Click)
-      lastAccessTime = System.currentTimeMillis();
+      lastAccessTime = System.nanoTime();
       return value;
     }
 

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

@@ -5,6 +5,7 @@ import io.ebean.cache.ServerCache;
 import io.ebean.cache.ServerCacheFactory;
 import io.ebean.cache.ServerCacheOptions;
 import io.ebean.cache.ServerCacheType;
+import io.ebean.config.CurrentTenantProvider;
 
 
 /**
@@ -29,9 +30,9 @@ class DefaultServerCacheFactory implements ServerCacheFactory {
   }
 
   @Override
-  public ServerCache createCache(ServerCacheType type, String cacheKey, ServerCacheOptions cacheOptions) {
+  public ServerCache createCache(ServerCacheType type, String cacheKey, CurrentTenantProvider tenantProvider, ServerCacheOptions cacheOptions) {
 
-    DefaultServerCache cache = new DefaultServerCache(cacheKey, cacheOptions);
+    DefaultServerCache cache = new DefaultServerCache(cacheKey, tenantProvider, cacheOptions);
     if (executor != null) {
       cache.periodicTrim(executor);
     }

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

@@ -6,9 +6,6 @@ import io.ebean.cache.ServerCacheOptions;
 import io.ebean.cache.ServerCacheType;
 import io.ebean.config.CurrentTenantProvider;
 
-import java.util.function.Supplier;
-
-
 /**
  * Manages the bean and query caches.
  */
@@ -48,12 +45,12 @@ public class DefaultServerCacheManager implements SpiCacheManager {
   }
 
   @Override
-  public Supplier<ServerCache> getCollectionIdsCache(Class<?> beanType, String propertyName) {
+  public ServerCache getCollectionIdsCache(Class<?> beanType, String propertyName) {
     return cacheHolder.getCache(beanType, name(beanType) + "." + propertyName, ServerCacheType.COLLECTION_IDS);
   }
 
   @Override
-  public Supplier<ServerCache> getNaturalKeyCache(Class<?> beanType) {
+  public ServerCache getNaturalKeyCache(Class<?> beanType) {
     return cacheHolder.getCache(beanType, name(beanType), ServerCacheType.NATURAL_KEY);
   }
 
@@ -61,7 +58,7 @@ public class DefaultServerCacheManager implements SpiCacheManager {
    * Return the query cache for a given bean type.
    */
   @Override
-  public Supplier<ServerCache> getQueryCache(Class<?> beanType) {
+  public ServerCache getQueryCache(Class<?> beanType) {
     return cacheHolder.getCache(beanType, name(beanType), ServerCacheType.QUERY);
   }
 
@@ -69,7 +66,7 @@ public class DefaultServerCacheManager implements SpiCacheManager {
    * Return the bean cache for a given bean type.
    */
   @Override
-  public Supplier<ServerCache> getBeanCache(Class<?> beanType) {
+  public ServerCache getBeanCache(Class<?> beanType) {
     return cacheHolder.getCache(beanType, name(beanType), ServerCacheType.BEAN);
   }
 

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

@@ -2,8 +2,6 @@ package io.ebeaninternal.server.cache;
 
 import io.ebean.cache.ServerCache;
 
-import java.util.function.Supplier;
-
 /**
  * The cache service for server side caching of beans and query results.
  */
@@ -21,22 +19,22 @@ public interface SpiCacheManager {
   /**
    * Return the cache for mapping natural keys to id values.
    */
-  Supplier<ServerCache> getNaturalKeyCache(Class<?> beanType);
+  ServerCache getNaturalKeyCache(Class<?> beanType);
 
   /**
    * Return the cache for beans of a particular type.
    */
-  Supplier<ServerCache> getBeanCache(Class<?> beanType);
+  ServerCache getBeanCache(Class<?> beanType);
 
   /**
    * Return the cache for associated many properties of a bean type.
    */
-  Supplier<ServerCache> getCollectionIdsCache(Class<?> beanType, String propertyName);
+  ServerCache getCollectionIdsCache(Class<?> beanType, String propertyName);
 
   /**
    * Return the cache for query results of a particular type of bean.
    */
-  Supplier<ServerCache> getQueryCache(Class<?> beanType);
+  ServerCache getQueryCache(Class<?> beanType);
 
   /**
    * Clear all the caches.

src/main/java/io/ebeaninternal/server/changelog/DefaultChangeLogRegister.java

@@ -52,7 +52,7 @@ public class DefaultChangeLogRegister implements ChangeLogRegister {
    * Find and return the ChangeLog annotation in the inheritance hierarchy.
    */
   private ChangeLog getChangeLog(Class<?> beanType) {
-    return AnnotationBase.findAnnotation(beanType, ChangeLog.class);
+    return AnnotationBase.findAnnotationRecursive(beanType, ChangeLog.class);
   }
 
   /**