#197 - Add Query findEach() findEachWhile() ... as better method names for findVisit(). More consistent with forEach() methods

src/main/java/com/avaje/ebean/EbeanServer.java

@@ -457,6 +457,30 @@ public interface EbeanServer {
    * Execute the query visiting the results. This is similar to findIterate in
    * that not all the result beans need to be held in memory at the same time
    * and as such is go for processing large queries.
+   *
+   * @see Query#findEach(QueryEachConsumer)
+   */
+  public <T> void findEach(Query<T> query, QueryEachConsumer<T> consumer, Transaction transaction);
+
+  /**
+   * Execute the query visiting the results. This is similar to findIterate in
+   * that not all the result beans need to be held in memory at the same time
+   * and as such is go for processing large queries.
+   *
+   * @see Query#findEachWhile(QueryEachWhileConsumer)
+   */
+  public <T> void findEachWhile(Query<T> query, QueryEachWhileConsumer<T> consumer, Transaction transaction);
+
+  /**
+   * Deprecated in favor of #findEachWhile which is functionally exactly the same
+   * but has a much better name.
+   * <p>
+   * Execute the query visiting the results. This is similar to findIterate in
+   * that not all the result beans need to be held in memory at the same time
+   * and as such is go for processing large queries.
+   * </p>
+   *
+   * @deprecated
    */
   public <T> void findVisit(Query<T> query, QueryResultVisitor<T> visitor, Transaction transaction);
 

src/main/java/com/avaje/ebean/ExpressionList.java

@@ -102,9 +102,25 @@ public interface ExpressionList<T> extends Serializable {
   public QueryIterator<T> findIterate();
 
   /**
-   * Execute the query visiting the results.
-   * 
-   * @see Query#findVisit(QueryResultVisitor)
+   * Execute the query process the beans one at a time.
+   *
+   * @see Query#findEach(QueryEachConsumer)
+   */
+  public void findEach(QueryEachConsumer<T> consumer);
+
+  /**
+   * Execute the query processing the beans one at a time with the ability to
+   * stop processing before reading all the beans.
+   *
+   * @see Query#findEachWhile(QueryEachWhileConsumer)
+   */
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer);
+
+  /**
+   * Deprecated in favor of #findEachWhile which is functionally exactly the same
+   * but has a much better name.
+   *
+   * @deprecated
    */
   public void findVisit(QueryResultVisitor<T> visitor);
 

src/main/java/com/avaje/ebean/Model.java

@@ -328,6 +328,37 @@ public abstract class Model {
       return query().findIds();
     }
 
+    /**
+     * Execute the query consuming each bean one at a time.
+     * <p>
+     * This is generally used to process large queries where unlike findList
+     * you do not want to hold all the results in memory at once but instead
+     * process them one at a time (requiring far less memory).
+     * </p>
+     * Equivalent to {@link Query#findEach(QueryEachConsumer)}
+     */
+    public void findEach(QueryEachConsumer<T> consumer) {
+      query().findEach(consumer);
+    }
+
+    /**
+     * Execute the query consuming each bean one at a time.
+     * <p>
+     * This is similar to #findEach except that you return boolean
+     * true to continue processing beans and return false to stop
+     * processing early.
+     * </p>
+     * <p>
+     * This is generally used to process large queries where unlike findList
+     * you do not want to hold all the results in memory at once but instead
+     * process them one at a time (requiring far less memory).
+     * </p>
+     * Equivalent to {@link Query#findEachWhile(QueryEachWhileConsumer)}
+     */
+    public void findEachWhile(QueryEachWhileConsumer<T> consumer) {
+      query().findEachWhile(consumer);
+    }
+
     /**
      * Retrieves all entities of the given type.
      * <p>

src/main/java/com/avaje/ebean/Query.java

@@ -446,37 +446,89 @@ public interface Query<T> extends Serializable {
    */
   public QueryIterator<T> findIterate();
 
+  /**
+   * This is deprecated in favor of #findEachWhile.
+   * <p>
+   * This is functionally exactly the same as #findEachWhile.  It is
+   * replaced by findEachWhile because the method name is much better.
+   * </p>
+   *
+   * @param visitor
+   *          the visitor used to process the queried beans.
+   *
+   * @deprecated
+   */
+  public void findVisit(QueryResultVisitor<T> visitor);
+
+  /**
+   * Execute the query processing the beans one at a time.
+   * <p>
+   * This method is appropriate to process very large query results as the
+   * beans are consumed one at a time and do not need to be held in memory
+   * (unlike #findList #findSet etc)
+   * </p>
+   * <p>
+   * Compared with #findEachWhile this will always process all the beans where as
+   * #findEachWhile provides a way to stop processing the query result early before
+   * all the beans have been read.
+   * </p>
+   * <p>
+   * This method is functionally equivalent to findIterate() but instead of using an
+   * iterator uses the QueryEachConsumer (SAM) interface which is better suited to use
+   * with Java8 closures.
+   * </p>
+   *
+   * <pre class="code">
+   *
+   * Query&lt;Customer&gt; query = server.find(Customer.class)
+   *     .where().gt(&quot;id&quot;, 0)
+   *     .orderBy(&quot;id&quot;)
+   *     .setMaxRows(2);
+   *
+   * query.findVisit((Customer customer) -> {
+   *
+   *     // do something with customer
+   *     System.out.println(&quot;-- visit &quot; + customer);
+   * });
+   * </pre>
+   *
+   * @param consumer
+   *          the consumer used to process the queried beans.
+   */
+  public void findEach(QueryEachConsumer<T> consumer);
+
   /**
    * Execute the query using callbacks to a visitor to process the resulting
    * beans one at a time.
    * <p>
-   * Similar to findIterate() this query method does not require all the result
-   * beans to be all held in memory at once and as such is useful for processing
-   * large queries.
+   * This method is functionally equivalent to findIterate() but instead of using an
+   * iterator uses the QueryEachWhileConsumer (SAM) interface which is better suited to use
+   * with Java8 closures.
    * </p>
-   * 
+
+   *
    * <pre class="code">
-   * 
+   *
    * Query&lt;Customer&gt; query = server.find(Customer.class)
    *     .fetch(&quot;contacts&quot;, new FetchConfig().query(2))
    *     .where().gt(&quot;id&quot;, 0)
    *     .orderBy(&quot;id&quot;)
    *     .setMaxRows(2);
-   * 
-   * query.findVisit(new QueryResultVisitor&lt;Customer&gt;() {
-   * 
-   *   public boolean accept(Customer customer) {
+   *
+   * query.findEachWhile((Customer customer) -> {
+   *
    *     // do something with customer
    *     System.out.println(&quot;-- visit &quot; + customer);
-   *     return true;
-   *   }
+   *
+   *     // return true to continue processing or false to stop
+   *     return (customer.getId() < 40);
    * });
    * </pre>
-   * 
-   * @param visitor
-   *          the visitor used to process the queried beans.
+   *
+   * @param consumer
+   *          the consumer used to process the queried beans.
    */
-  public void findVisit(QueryResultVisitor<T> visitor);
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer);
 
   /**
    * Execute the query returning the list of objects.

src/main/java/com/avaje/ebean/QueryEachConsumer.java

@@ -0,0 +1,41 @@
+package com.avaje.ebean;
+
+/**
+ * Used to process a query result one bean at a time via a callback to this
+ * visitor.
+ * <p>
+ * If you wish to stop further processing return false from the accept method.
+ * </p>
+ * <p>
+ * Unlike findList() and findSet() using a QueryResultVisitor does not require
+ * all the beans in the query result to be held in memory at once. This makes
+ * QueryResultVisitor useful for processing large queries.
+ * </p>
+ *
+ * <pre class="code">
+ *
+ * Query&lt;Customer&gt; query = server.find(Customer.class)
+ *     .where().gt(&quot;id&quot;, 0)
+ *     .orderBy(&quot;id&quot;)
+ *     .setMaxRows(2);
+ *
+ * query.findVisit((Customer customer) -> {
+ *
+ *     // do something with customer
+ *     System.out.println(&quot;-- visit &quot; + customer);
+ * });
+ * </pre>
+ * 
+ * @param <T>
+ *          the type of entity bean being queried.
+ */
+public interface QueryEachConsumer<T> {
+
+  /**
+   * Process the bean.
+   * 
+   * @param bean
+   *          the entity bean to process
+   */
+  public void accept(T bean);
+}

src/main/java/com/avaje/ebean/QueryEachWhileConsumer.java

@@ -0,0 +1,45 @@
+package com.avaje.ebean;
+
+/**
+ * Used to process a query result one bean at a time via a callback to this
+ * visitor.
+ * <p>
+ * If you wish to stop further processing return false from the accept method.
+ * </p>
+ * <p>
+ * Unlike findList() and findSet() using a QueryResultVisitor does not require
+ * all the beans in the query result to be held in memory at once. This makes
+ * QueryResultVisitor useful for processing large queries.
+ * </p>
+ * <p/>
+ * <pre class="code">
+ *
+ * Query&lt;Customer&gt; query = server.find(Customer.class)
+ *     .fetch(&quot;contacts&quot;, new FetchConfig().query(2))
+ *     .where().gt(&quot;id&quot;, 0)
+ *     .orderBy(&quot;id&quot;)
+ *     .setMaxRows(2);
+ *
+ * query.findEachWhile((Customer customer) -> {
+ *
+ *     // do something with customer
+ *     System.out.println(&quot;-- visit &quot; + customer);
+ *
+ *     // return true to continue processing or false to stop
+ *     return (customer.getId() < 40);
+ * });
+ * </pre>
+ *
+ * @param <T> the type of entity bean being queried.
+ */
+public interface QueryEachWhileConsumer<T> {
+
+  /**
+   * Process the bean and return true if you want to continue processing more
+   * beans. Return false if you want to stop processing further.
+   *
+   * @param bean the entity bean to process
+   * @return true to continue processing more beans or false to stop.
+   */
+  public boolean accept(T bean);
+}

src/main/java/com/avaje/ebeaninternal/server/core/DefaultServer.java

@@ -17,36 +17,10 @@ import javax.management.MBeanServer;
 import javax.management.ObjectName;
 import javax.persistence.PersistenceException;
 
+import com.avaje.ebean.*;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.avaje.ebean.AdminAutofetch;
-import com.avaje.ebean.BackgroundExecutor;
-import com.avaje.ebean.BeanState;
-import com.avaje.ebean.CallableSql;
-import com.avaje.ebean.Ebean;
-import com.avaje.ebean.ExpressionFactory;
-import com.avaje.ebean.Filter;
-import com.avaje.ebean.FutureIds;
-import com.avaje.ebean.FutureList;
-import com.avaje.ebean.FutureRowCount;
-import com.avaje.ebean.PagedList;
-import com.avaje.ebean.PagingList;
-import com.avaje.ebean.Query;
-import com.avaje.ebean.QueryIterator;
-import com.avaje.ebean.QueryResultVisitor;
-import com.avaje.ebean.SqlFutureList;
-import com.avaje.ebean.SqlQuery;
-import com.avaje.ebean.SqlRow;
-import com.avaje.ebean.SqlUpdate;
-import com.avaje.ebean.Transaction;
-import com.avaje.ebean.TxCallable;
-import com.avaje.ebean.TxIsolation;
-import com.avaje.ebean.TxRunnable;
-import com.avaje.ebean.TxScope;
-import com.avaje.ebean.TxType;
-import com.avaje.ebean.Update;
-import com.avaje.ebean.ValuePair;
 import com.avaje.ebean.bean.BeanCollection;
 import com.avaje.ebean.bean.CallStack;
 import com.avaje.ebean.bean.EntityBean;
@@ -273,17 +247,14 @@ public final class DefaultServer implements SpiEbeanServer {
     
     List<SpiEbeanPlugin> spiPlugins = new ArrayList<SpiEbeanPlugin>();
 
-    final Iterator<SpiEbeanPlugin> plugins = ServiceLoader.load(SpiEbeanPlugin.class).iterator();
-
-    while (plugins.hasNext()) {
-      SpiEbeanPlugin plugin = plugins.next();
+    for (SpiEbeanPlugin plugin : ServiceLoader.load(SpiEbeanPlugin.class)) {
       spiPlugins.add(plugin);
       plugin.setup(this, this.getDatabasePlatform(), config.getServerConfig());
 
       if (plugin instanceof DdlGenerator) {
         // backwards compatible
-        ddlGenerator = (DdlGenerator)plugin;
-      } 
+        ddlGenerator = (DdlGenerator) plugin;
+      }
     }
     
     if (ddlGenerator == null) {
@@ -1413,12 +1384,27 @@ public final class DefaultServer implements SpiEbeanServer {
 
     SpiOrmQueryRequest<T> request = createQueryRequest(Type.LIST, query, t);
 
-    try {
-      request.initTransIfRequired();
-      request.findVisit(visitor);
-    } finally {
-      // do nothing - findVisit garuntee's cleanup of the transaction if required
-    }
+    request.initTransIfRequired();
+    request.findVisit(visitor);
+    // no try finally - findVisit guarantee's cleanup of the transaction if required
+  }
+
+  public <T> void findEach(Query<T> query, QueryEachConsumer<T> consumer, Transaction t) {
+
+    SpiOrmQueryRequest<T> request = createQueryRequest(Type.LIST, query, t);
+
+    request.initTransIfRequired();
+    request.findEach(consumer);
+    // no try finally - findVisit guarantee's cleanup of the transaction if required
+  }
+
+  public <T> void findEachWhile(Query<T> query, QueryEachWhileConsumer<T> consumer, Transaction t) {
+
+    SpiOrmQueryRequest<T> request = createQueryRequest(Type.LIST, query, t);
+
+    request.initTransIfRequired();
+    request.findEachWhile(consumer);
+    // no try finally - findVisit guarantee's cleanup of the transaction if required
   }
 
   public <T> QueryIterator<T> findIterate(Query<T> query, Transaction t) {
@@ -1542,7 +1528,7 @@ public final class DefaultServer implements SpiEbeanServer {
   
   @Override
   public void markAsDirty(Object bean) {
-    if (bean instanceof EntityBean == false) {
+    if (!(bean instanceof EntityBean)) {
       throw new IllegalArgumentException("This bean is not an EntityBean?");
     }
     // mark the bean as dirty (so that an update will not get skipped)
@@ -1650,7 +1636,7 @@ public final class DefaultServer implements SpiEbeanServer {
     if (bean == null) {
       throw new IllegalArgumentException(Message.msg("bean.isnull"));
     }
-    if (bean instanceof EntityBean == false) {
+    if (!(bean instanceof EntityBean)) {
       throw new IllegalArgumentException("Was expecting an EntityBean but got a "+bean.getClass());
     }
     return (EntityBean)bean;
@@ -1959,10 +1945,7 @@ public final class DefaultServer implements SpiEbeanServer {
   public boolean isSupportedType(java.lang.reflect.Type genericType) {
 
     TypeInfo typeInfo = ParamTypeHelper.getTypeInfo(genericType);
-    if (typeInfo == null) {
-      return false;
-    }
-    return getBeanDescriptor(typeInfo.getBeanType()) != null;
+    return typeInfo != null && getBeanDescriptor(typeInfo.getBeanType()) != null;
   }
 
   public Object getBeanId(Object bean) {

src/main/java/com/avaje/ebeaninternal/server/core/OrmQueryRequest.java

@@ -6,9 +6,7 @@ import java.util.Set;
 
 import javax.persistence.PersistenceException;
 
-import com.avaje.ebean.QueryIterator;
-import com.avaje.ebean.QueryResultVisitor;
-import com.avaje.ebean.RawSql;
+import com.avaje.ebean.*;
 import com.avaje.ebean.bean.BeanCollection;
 import com.avaje.ebean.bean.PersistenceContext;
 import com.avaje.ebean.event.BeanFinder;
@@ -234,6 +232,30 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
     return idList.getIdList();
   }
 
+  public void findEach(QueryEachConsumer<T> consumer) {
+    QueryIterator<T> it = queryEngine.findIterate(this);
+    try {
+      while (it.hasNext()) {
+        consumer.accept(it.next());
+      }
+    } finally {
+      it.close();
+    }
+  }
+
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer) {
+    QueryIterator<T> it = queryEngine.findIterate(this);
+    try {
+      while (it.hasNext()) {
+        if (!consumer.accept(it.next())) {
+          break;
+        }
+      }
+    } finally {
+      it.close();
+    }
+  }
+
   public void findVisit(QueryResultVisitor<T> visitor) {
     QueryIterator<T> it = queryEngine.findIterate(this);
     try {

src/main/java/com/avaje/ebeaninternal/server/core/SpiOrmQueryRequest.java

@@ -4,6 +4,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import com.avaje.ebean.QueryEachConsumer;
+import com.avaje.ebean.QueryEachWhileConsumer;
 import com.avaje.ebean.QueryIterator;
 import com.avaje.ebean.QueryResultVisitor;
 import com.avaje.ebean.bean.BeanCollection;
@@ -65,7 +67,17 @@ public interface SpiOrmQueryRequest<T> {
      */
     public void findVisit(QueryResultVisitor<T> visitor);
 
-    /**
+  /**
+   * Execute the find returning a QueryIterator and visitor pattern.
+   */
+  public void findEach(QueryEachConsumer<T> consumer);
+
+  /**
+   * Execute the find returning a QueryIterator and visitor pattern.
+   */
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer);
+
+  /**
      * Execute the find returning a QueryIterator.
      */
     public QueryIterator<T> findIterate();

src/main/java/com/avaje/ebeaninternal/server/expression/JunctionExpression.java

@@ -218,6 +218,16 @@ abstract class JunctionExpression<T> implements Junction<T>, SpiExpression, Expr
     return exprList.findIds();
   }
 
+  @Override
+  public void findEach(QueryEachConsumer<T> consumer) {
+    exprList.findEach(consumer);
+  }
+
+  @Override
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer) {
+    exprList.findEachWhile(consumer);
+  }
+
   public void findVisit(QueryResultVisitor<T> visitor) {
     exprList.findVisit(visitor);
   }

src/main/java/com/avaje/ebeaninternal/server/querydefn/DefaultOrmQuery.java

@@ -8,22 +8,8 @@ import java.util.Set;
 
 import javax.persistence.PersistenceException;
 
-import com.avaje.ebean.EbeanServer;
-import com.avaje.ebean.Expression;
-import com.avaje.ebean.ExpressionFactory;
-import com.avaje.ebean.ExpressionList;
-import com.avaje.ebean.FetchConfig;
-import com.avaje.ebean.FutureIds;
-import com.avaje.ebean.FutureList;
-import com.avaje.ebean.FutureRowCount;
-import com.avaje.ebean.OrderBy;
+import com.avaje.ebean.*;
 import com.avaje.ebean.OrderBy.Property;
-import com.avaje.ebean.PagedList;
-import com.avaje.ebean.PagingList;
-import com.avaje.ebean.Query;
-import com.avaje.ebean.QueryIterator;
-import com.avaje.ebean.QueryResultVisitor;
-import com.avaje.ebean.RawSql;
 import com.avaje.ebean.bean.BeanCollectionTouched;
 import com.avaje.ebean.bean.CallStack;
 import com.avaje.ebean.bean.EntityBean;
@@ -911,6 +897,16 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
     server.findVisit(this, visitor, null);
   }
 
+  @Override
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer) {
+    server.findEachWhile(this, consumer, null);
+  }
+
+  @Override
+  public void findEach(QueryEachConsumer<T> consumer) {
+    server.findEach(this, consumer, null);
+  }
+
   public QueryIterator<T> findIterate() {
     return server.findIterate(this, null);
   }

src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionList.java

@@ -6,19 +6,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
-import com.avaje.ebean.Expression;
-import com.avaje.ebean.ExpressionFactory;
-import com.avaje.ebean.ExpressionList;
-import com.avaje.ebean.FutureIds;
-import com.avaje.ebean.FutureList;
-import com.avaje.ebean.FutureRowCount;
-import com.avaje.ebean.Junction;
-import com.avaje.ebean.OrderBy;
-import com.avaje.ebean.PagedList;
-import com.avaje.ebean.PagingList;
-import com.avaje.ebean.Query;
-import com.avaje.ebean.QueryIterator;
-import com.avaje.ebean.QueryResultVisitor;
+import com.avaje.ebean.*;
 import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebean.text.PathProperties;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
@@ -172,6 +160,16 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     return query.findIds();
   }
 
+  @Override
+  public void findEach(QueryEachConsumer<T> consumer) {
+    query.findEach(consumer);
+  }
+
+  @Override
+  public void findEachWhile(QueryEachWhileConsumer<T> consumer) {
+    query.findEachWhile(consumer);
+  }
+
   public void findVisit(QueryResultVisitor<T> visitor) {
     query.findVisit(visitor);
   }