HHH-5348 - support for TypedQuery jpaql/hql "scalar" queries

hibernate-core/src/main/java/org/hibernate/engine/query/HQLQueryPlan.java

@@ -1,10 +1,10 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,7 +20,6 @@
  * Free Software Foundation, Inc.
  * 51 Franklin Street, Fifth Floor
  * Boston, MA  02110-1301  USA
- *
  */
 package org.hibernate.engine.query;
 
@@ -32,6 +31,9 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+
+import org.jboss.logging.Logger;
+
 import org.hibernate.HibernateException;
 import org.hibernate.HibernateLogger;
 import org.hibernate.QueryException;
@@ -50,7 +52,6 @@ import org.hibernate.internal.util.collections.EmptyIterator;
 import org.hibernate.internal.util.collections.IdentitySet;
 import org.hibernate.internal.util.collections.JoinedIterator;
 import org.hibernate.type.Type;
-import org.jboss.logging.Logger;
 
 /**
  * Defines a query execution plan for an HQL query (or filter).
@@ -331,4 +332,8 @@ public class HQLQueryPlan implements Serializable {
 		System.arraycopy(translators, 0, copy, 0, copy.length);
 		return copy;
 	}
+
+	public Class getDynamicInstantiationResultType() {
+		return translators[0].getDynamicInstantiationResultType();
+	}
 }

hibernate-core/src/main/java/org/hibernate/hql/QueryTranslator.java

@@ -1,10 +1,10 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,13 +20,14 @@
  * Free Software Foundation, Inc.
  * 51 Franklin Street, Fifth Floor
  * Boston, MA  02110-1301  USA
- *
  */
 package org.hibernate.hql;
+
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+
 import org.hibernate.HibernateException;
 import org.hibernate.MappingException;
 import org.hibernate.QueryException;
@@ -185,4 +186,6 @@ public interface QueryTranslator {
 	boolean containsCollectionFetches();
 
 	boolean isManipulationStatement();
+
+	public Class getDynamicInstantiationResultType();
 }

hibernate-core/src/main/java/org/hibernate/hql/ast/QueryTranslatorImpl.java

@@ -1,10 +1,10 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,7 +20,6 @@
  * Free Software Foundation, Inc.
  * 51 Franklin Street, Fifth Floor
  * Boston, MA  02110-1301  USA
- *
  */
 package org.hibernate.hql.ast;
 
@@ -30,6 +29,13 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+
+import antlr.ANTLRException;
+import antlr.RecognitionException;
+import antlr.TokenStreamException;
+import antlr.collections.AST;
+import org.jboss.logging.Logger;
+
 import org.hibernate.HibernateException;
 import org.hibernate.HibernateLogger;
 import org.hibernate.MappingException;
@@ -50,6 +56,7 @@ import org.hibernate.hql.ast.exec.BasicExecutor;
 import org.hibernate.hql.ast.exec.MultiTableDeleteExecutor;
 import org.hibernate.hql.ast.exec.MultiTableUpdateExecutor;
 import org.hibernate.hql.ast.exec.StatementExecutor;
+import org.hibernate.hql.ast.tree.AggregatedSelectExpression;
 import org.hibernate.hql.ast.tree.FromElement;
 import org.hibernate.hql.ast.tree.InsertStatement;
 import org.hibernate.hql.ast.tree.QueryNode;
@@ -63,11 +70,6 @@ import org.hibernate.internal.util.collections.IdentitySet;
 import org.hibernate.loader.hql.QueryLoader;
 import org.hibernate.persister.entity.Queryable;
 import org.hibernate.type.Type;
-import org.jboss.logging.Logger;
-import antlr.ANTLRException;
-import antlr.RecognitionException;
-import antlr.TokenStreamException;
-import antlr.collections.AST;
 
 /**
  * A QueryTranslator that uses an Antlr-based parser.
@@ -564,6 +566,12 @@ public class QueryTranslatorImpl implements FilterTranslator {
 		return collectedParameterSpecifications;
 	}
 
+	@Override
+	public Class getDynamicInstantiationResultType() {
+		AggregatedSelectExpression aggregation = queryLoader.getAggregatedSelectExpression();
+		return aggregation == null ? null : aggregation.getAggregationResultType();
+	}
+
 	public static class JavaConstantConverter implements NodeTraverser.VisitationStrategy {
 		private AST dotRoot;
 		public void visit(AST node) {

hibernate-core/src/main/java/org/hibernate/hql/ast/tree/AggregatedSelectExpression.java

@@ -1,8 +1,10 @@
 /*
- * Copyright (c) 2009, Red Hat Middleware LLC or third-party contributors as
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2009-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,7 +22,9 @@
  * Boston, MA  02110-1301  USA
  */
 package org.hibernate.hql.ast.tree;
+
 import java.util.List;
+
 import org.hibernate.transform.ResultTransformer;
 
 /**
@@ -50,4 +54,11 @@ public interface AggregatedSelectExpression extends SelectExpression {
 	 * @return The appropriate transformer
 	 */
 	public ResultTransformer getResultTransformer();
+
+	/**
+	 * Obtain the java type of the aggregation
+	 *
+	 * @return The java type.
+	 */
+	public Class getAggregationResultType();
 }

hibernate-core/src/main/java/org/hibernate/hql/ast/tree/ConstructorNode.java

@@ -1,10 +1,10 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,13 +20,17 @@
  * Free Software Foundation, Inc.
  * 51 Franklin Street, Fifth Floor
  * Boston, MA  02110-1301  USA
- *
  */
 package org.hibernate.hql.ast.tree;
 
 import java.lang.reflect.Constructor;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Map;
+
+import antlr.SemanticException;
+import antlr.collections.AST;
+
 import org.hibernate.PropertyNotFoundException;
 import org.hibernate.QueryException;
 import org.hibernate.hql.ast.DetailedSemanticException;
@@ -36,8 +40,6 @@ import org.hibernate.transform.AliasToBeanConstructorResultTransformer;
 import org.hibernate.transform.ResultTransformer;
 import org.hibernate.transform.Transformers;
 import org.hibernate.type.Type;
-import antlr.SemanticException;
-import antlr.collections.AST;
 
 /**
  * Represents a constructor (new) in a SELECT.
@@ -45,11 +47,11 @@ import antlr.collections.AST;
  * @author josh
  */
 public class ConstructorNode extends SelectExpressionList implements AggregatedSelectExpression {
+	private Class resultType;
 	private Constructor constructor;
 	private Type[] constructorArgumentTypes;
 	private boolean isMap;
 	private boolean isList;
-	private int scalarColumnIndex = -1;
 
 	public ResultTransformer getResultTransformer() {
 		if ( constructor != null ) {
@@ -64,14 +66,6 @@ public class ConstructorNode extends SelectExpressionList implements AggregatedS
 		throw new QueryException( "Unable to determine proper dynamic-instantiation tranformer to use." );
 	}
 
-	public boolean isMap() {
-		return isMap;
-	}
-
-	public boolean isList() {
-		return isList;
-	}
-
 	private String[] aggregatedAliases;
 
 	public String[] getAggregatedAliases() {
@@ -101,7 +95,7 @@ public class ConstructorNode extends SelectExpressionList implements AggregatedS
 	}
 
 	public int getScalarColumnIndex() {
-		return scalarColumnIndex;
+		return -1;
 	}
 
 	public void setScalarColumnText(int i) throws SemanticException {
@@ -119,6 +113,11 @@ public class ConstructorNode extends SelectExpressionList implements AggregatedS
 		return getFirstChild().getNextSibling();
 	}
 
+	@Override
+	public Class getAggregationResultType() {
+		return resultType;
+	}
+
 	/**
 	 * @deprecated (tell clover to ignore this method)
 	 */
@@ -143,12 +142,15 @@ public class ConstructorNode extends SelectExpressionList implements AggregatedS
 		String path = ( ( PathNode ) getFirstChild() ).getPath();
 		if ( "map".equals( path.toLowerCase() ) ) {
 			isMap = true;
+			resultType = Map.class;
 		}
 		else if ( "list".equals( path.toLowerCase() ) ) {
 			isList = true;
+			resultType = List.class;
 		}
 		else {
-			constructor = resolveConstructor(path);
+			constructor = resolveConstructor( path );
+			resultType = constructor.getDeclaringClass();
 		}
 	}
 

hibernate-core/src/main/java/org/hibernate/hql/ast/tree/MapEntryNode.java

@@ -63,6 +63,11 @@ public class MapEntryNode extends AbstractMapComponentNode implements Aggregated
 		return "entry(*)";
 	}
 
+	@Override
+	public Class getAggregationResultType() {
+		return Map.Entry.class;
+	}
+
 	protected Type resolveType(QueryableCollection collectionPersister) {
 		Type keyType = collectionPersister.getIndexType();
 		Type valueType = collectionPersister.getElementType();

hibernate-core/src/main/java/org/hibernate/hql/classic/QueryTranslatorImpl.java

@@ -1193,6 +1193,11 @@ public class QueryTranslatorImpl extends BasicLoader implements FilterTranslator
 		return false;
 	}
 
+	@Override
+	public Class getDynamicInstantiationResultType() {
+		return holderClass;
+	}
+
 	public ParameterTranslations getParameterTranslations() {
 		return new ParameterTranslations() {
 

hibernate-core/src/main/java/org/hibernate/loader/hql/QueryLoader.java

@@ -1,10 +1,10 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
- * distributed under license by Red Hat Middleware LLC.
+ * distributed under license by Red Hat Inc.
  *
  * This copyrighted material is made available to anyone wishing to use, modify,
  * copy, or redistribute it subject to the terms and conditions of the GNU
@@ -20,9 +20,9 @@
  * Free Software Foundation, Inc.
  * 51 Franklin Street, Fifth Floor
  * Boston, MA  02110-1301  USA
- *
  */
 package org.hibernate.loader.hql;
+
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -31,6 +31,7 @@ import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+
 import org.hibernate.HibernateException;
 import org.hibernate.LockMode;
 import org.hibernate.LockOptions;
@@ -96,7 +97,7 @@ public class QueryLoader extends BasicLoader {
 
 	private int selectLength;
 
-	private ResultTransformer implicitResultTransformer;
+	private AggregatedSelectExpression aggregatedSelectExpression;
 	private String[] queryReturnAliases;
 
 	private LockMode[] defaultLockModes;
@@ -128,10 +129,7 @@ public class QueryLoader extends BasicLoader {
 		//sqlResultTypes = selectClause.getSqlResultTypes();
 		queryReturnTypes = selectClause.getQueryReturnTypes();
 
-		AggregatedSelectExpression aggregatedSelectExpression = selectClause.getAggregatedSelectExpression();
-		implicitResultTransformer = aggregatedSelectExpression == null
-				? null
-				: aggregatedSelectExpression.getResultTransformer();
+		aggregatedSelectExpression = selectClause.getAggregatedSelectExpression();
 		queryReturnAliases = selectClause.getQueryReturnAliases();
 
 		List collectionFromElements = selectClause.getCollectionFromElements();
@@ -199,6 +197,11 @@ public class QueryLoader extends BasicLoader {
 		defaultLockModes = ArrayHelper.fillArray( LockMode.NONE, size );
 	}
 
+	public AggregatedSelectExpression getAggregatedSelectExpression() {
+		return aggregatedSelectExpression;
+	}
+
+
 	// -- Loader implementation --
 
 	public final void validateScrollability() throws HibernateException {
@@ -375,7 +378,7 @@ public class QueryLoader extends BasicLoader {
 	}
 
 	private boolean hasSelectNew() {
-		return implicitResultTransformer != null;
+		return aggregatedSelectExpression != null &&  aggregatedSelectExpression.getResultTransformer() != null;
 	}
 
 	protected String[] getResultRowAliases() {
@@ -383,6 +386,9 @@ public class QueryLoader extends BasicLoader {
 	}
 	
 	protected ResultTransformer resolveResultTransformer(ResultTransformer resultTransformer) {
+		final ResultTransformer implicitResultTransformer = aggregatedSelectExpression == null
+				? null
+				: aggregatedSelectExpression.getResultTransformer();
 		return HolderInstantiator.resolveResultTransformer( implicitResultTransformer, resultTransformer );
 	}
 
@@ -446,6 +452,9 @@ public class QueryLoader extends BasicLoader {
 	}
 
 	private HolderInstantiator buildHolderInstantiator(ResultTransformer queryLocalResultTransformer) {
+		final ResultTransformer implicitResultTransformer = aggregatedSelectExpression == null
+				? null
+				: aggregatedSelectExpression.getResultTransformer();
 		return HolderInstantiator.getHolderInstantiator(
 				implicitResultTransformer,
 				queryLocalResultTransformer,

hibernate-entitymanager/src/main/java/org/hibernate/ejb/AbstractEntityManagerImpl.java

@@ -23,15 +23,6 @@
  */
 package org.hibernate.ejb;
 
-import java.io.IOException;
-import java.io.ObjectInputStream;
-import java.io.ObjectOutputStream;
-import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 import javax.persistence.CacheRetrieveMode;
 import javax.persistence.CacheStoreMode;
 import javax.persistence.EntityManager;
@@ -60,6 +51,18 @@ import javax.persistence.metamodel.Metamodel;
 import javax.persistence.spi.PersistenceUnitTransactionType;
 import javax.transaction.SystemException;
 import javax.transaction.TransactionManager;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.jboss.logging.Logger;
+
 import org.hibernate.AssertionFailure;
 import org.hibernate.CacheMode;
 import org.hibernate.FlushMode;
@@ -88,6 +91,7 @@ import org.hibernate.engine.NamedSQLQueryDefinition;
 import org.hibernate.engine.ResultSetMappingDefinition;
 import org.hibernate.engine.SessionFactoryImplementor;
 import org.hibernate.engine.SessionImplementor;
+import org.hibernate.engine.query.HQLQueryPlan;
 import org.hibernate.engine.query.sql.NativeSQLQueryReturn;
 import org.hibernate.engine.query.sql.NativeSQLQueryRootReturn;
 import org.hibernate.engine.transaction.internal.jta.JtaStatusHelper;
@@ -99,10 +103,11 @@ import org.hibernate.engine.transaction.synchronization.spi.ExceptionMapper;
 import org.hibernate.engine.transaction.synchronization.spi.ManagedFlushChecker;
 import org.hibernate.engine.transaction.synchronization.spi.SynchronizationCallbackCoordinator;
 import org.hibernate.internal.util.ReflectHelper;
+import org.hibernate.internal.util.collections.CollectionHelper;
 import org.hibernate.proxy.HibernateProxy;
 import org.hibernate.service.jta.platform.spi.JtaPlatform;
 import org.hibernate.transform.BasicTransformerAdapter;
-import org.jboss.logging.Logger;
+import org.hibernate.type.Type;
 
 /**
  * @author <a href="mailto:gavin@hibernate.org">Gavin King</a>
@@ -279,18 +284,51 @@ public abstract class AbstractEntityManagerImpl implements HibernateEntityManage
 
 	public <T> TypedQuery<T> createQuery(String jpaqlString, Class<T> resultClass) {
 		try {
+			// do the translation
 			org.hibernate.Query hqlQuery = getSession().createQuery( jpaqlString );
-			if ( hqlQuery.getReturnTypes().length != 1 ) {
-				throw new IllegalArgumentException( "Cannot create TypedQuery for query with more than one return" );
+
+			// do some validation checking
+			if ( Object[].class.equals( resultClass ) ) {
+				// no validation needed
 			}
-			if ( !resultClass.isAssignableFrom( hqlQuery.getReturnTypes()[0].getReturnedClass() ) ) {
-				throw new IllegalArgumentException(
-						"Type specified for TypedQuery [" +
-								resultClass.getName() +
-								"] is incompatible with query return type [" +
-								hqlQuery.getReturnTypes()[0].getReturnedClass() + "]"
-				);
+			else if ( Tuple.class.equals( resultClass ) ) {
+				TupleBuilderTransformer tupleTransformer = new TupleBuilderTransformer( hqlQuery );
+				hqlQuery.setResultTransformer( tupleTransformer  );
 			}
+			else {
+				final HQLQueryPlan queryPlan = unwrap( SessionImplementor.class )
+						.getFactory()
+						.getQueryPlanCache()
+						.getHQLQueryPlan( jpaqlString, false, null );
+				final Class dynamicInstantiationClass = queryPlan.getDynamicInstantiationResultType();
+				if ( dynamicInstantiationClass != null ) {
+					if ( ! resultClass.isAssignableFrom( dynamicInstantiationClass ) ) {
+						throw new IllegalArgumentException(
+								"Mismatch in requested result type [" + resultClass.getName() +
+										"] and actual result type [" + dynamicInstantiationClass.getName() + "]"
+						);
+					}
+				}
+				else if ( hqlQuery.getReturnTypes().length == 1 ) {
+					// if we have only a single return expression, its java type should match with the requested type
+					if ( !resultClass.isAssignableFrom( hqlQuery.getReturnTypes()[0].getReturnedClass() ) ) {
+						throw new IllegalArgumentException(
+								"Type specified for TypedQuery [" +
+										resultClass.getName() +
+										"] is incompatible with query return type [" +
+										hqlQuery.getReturnTypes()[0].getReturnedClass() + "]"
+						);
+					}
+				}
+				else {
+					throw new IllegalArgumentException(
+							"Cannot create TypedQuery for query with more than one return using requested result type [" +
+									resultClass.getName() + "]"
+					);
+				}
+			}
+
+			// finally, build/return the query instance
 			return new QueryImpl<T>( hqlQuery, this );
 		}
 		catch ( HibernateException he ) {
@@ -298,6 +336,139 @@ public abstract class AbstractEntityManagerImpl implements HibernateEntityManage
 		}
 	}
 
+	public static class TupleBuilderTransformer extends BasicTransformerAdapter {
+		private List<TupleElement<?>> tupleElements;
+		private Map<String,HqlTupleElementImpl> tupleElementsByAlias;
+
+		public TupleBuilderTransformer(org.hibernate.Query hqlQuery) {
+			final Type[] resultTypes = hqlQuery.getReturnTypes();
+			final int tupleSize = resultTypes.length;
+
+			this.tupleElements = CollectionHelper.arrayList( tupleSize );
+
+			final String[] aliases = hqlQuery.getReturnAliases();
+			final boolean hasAliases = aliases != null && aliases.length > 0;
+			this.tupleElementsByAlias = hasAliases
+					? CollectionHelper.mapOfSize( tupleSize )
+					: Collections.<String, HqlTupleElementImpl>emptyMap();
+
+			for ( int i = 0; i < tupleSize; i++ ) {
+				final HqlTupleElementImpl tupleElement = new HqlTupleElementImpl(
+						i,
+						aliases == null ? null : aliases[i],
+						resultTypes[i]
+				);
+				tupleElements.add( tupleElement );
+				if ( hasAliases ) {
+					final String alias = aliases[i];
+					if ( alias != null ) {
+						tupleElementsByAlias.put( alias, tupleElement );
+					}
+				}
+			}
+		}
+
+		@Override
+		public Object transformTuple(Object[] tuple, String[] aliases) {
+			if ( tuple.length != tupleElements.size() ) {
+				throw new IllegalArgumentException(
+						"Size mismatch between tuple result [" + tuple.length + "] and expected tuple elements [" +
+								tupleElements.size() + "]"
+				);
+			}
+			return new HqlTupleImpl( tuple );
+		}
+
+		public static class HqlTupleElementImpl<X> implements TupleElement<X> {
+			private final int position;
+			private final String alias;
+			private final Type hibernateType;
+
+			public HqlTupleElementImpl(int position, String alias, Type hibernateType) {
+				this.position = position;
+				this.alias = alias;
+				this.hibernateType = hibernateType;
+			}
+
+			@Override
+			public Class getJavaType() {
+				return hibernateType.getReturnedClass();
+			}
+
+			@Override
+			public String getAlias() {
+				return alias;
+			}
+
+			public int getPosition() {
+				return position;
+			}
+
+			public Type getHibernateType() {
+				return hibernateType;
+			}
+		}
+
+		public class HqlTupleImpl implements Tuple {
+			private Object[] tuple;
+
+			public HqlTupleImpl(Object[] tuple) {
+				this.tuple = tuple;
+			}
+
+			@Override
+			public <X> X get(String alias, Class<X> type) {
+				return (X) get( alias );
+			}
+
+			@Override
+			public Object get(String alias) {
+				HqlTupleElementImpl tupleElement = tupleElementsByAlias.get( alias );
+				if ( tupleElement == null ) {
+					throw new IllegalArgumentException( "Unknown alias [" + alias + "]" );
+				}
+				return tuple[ tupleElement.getPosition() ];
+			}
+
+			@Override
+			public <X> X get(int i, Class<X> type) {
+				return (X) get( i );
+			}
+
+			@Override
+			public Object get(int i) {
+				if ( i < 0 ) {
+					throw new IllegalArgumentException( "requested tuple index must be greater than zero" );
+				}
+				if ( i > tuple.length ) {
+					throw new IllegalArgumentException( "requested tuple index exceeds actual tuple size" );
+				}
+				return tuple[i];
+			}
+
+			@Override
+			public Object[] toArray() {
+				// todo : make a copy?
+				return tuple;
+			}
+
+			@Override
+			public List<TupleElement<?>> getElements() {
+				return tupleElements;
+			}
+
+			@Override
+			public <X> X get(TupleElement<X> tupleElement) {
+				if ( HqlTupleElementImpl.class.isInstance( tupleElement ) ) {
+					return get( ( (HqlTupleElementImpl) tupleElement ).getPosition(), tupleElement.getJavaType() );
+				}
+				else {
+					return get( tupleElement.getAlias(), tupleElement.getJavaType() );
+				}
+			}
+		}
+	}
+
 	public <T> TypedQuery<T> createQuery(
 			String jpaqlString,
 			Class<T> resultClass,

hibernate-entitymanager/src/test/java/org/hibernate/ejb/test/query/QueryTest.java

@@ -26,6 +26,7 @@ package org.hibernate.ejb.test.query;
 import javax.persistence.EntityManager;
 import javax.persistence.Query;
 import javax.persistence.TemporalType;
+import javax.persistence.Tuple;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
@@ -522,6 +523,33 @@ public class QueryTest extends BaseEntityManagerFunctionalTestCase {
 		em.close();
 	}
 
+	@Test
+	public void testTypedScalarQueries() {
+		EntityManager em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+		Item item = new Item( "Mouse", "Micro$oft mouse" );
+		em.persist( item );
+		assertTrue( em.contains( item ) );
+		em.getTransaction().commit();
+
+		em.getTransaction().begin();
+		Object[] itemData = em.createQuery( "select i.name,i.descr from Item i", Object[].class ).getSingleResult();
+		assertEquals( 2, itemData.length );
+		assertEquals( String.class, itemData[0].getClass() );
+		assertEquals( String.class, itemData[1].getClass() );
+		Tuple itemTuple = em.createQuery( "select i.name,i.descr from Item i", Tuple.class ).getSingleResult();
+		assertEquals( 2, itemTuple.getElements().size() );
+		assertEquals( String.class, itemTuple.get( 0 ).getClass() );
+		assertEquals( String.class, itemTuple.get( 1 ).getClass() );
+		Item itemView = em.createQuery( "select new Item(i.name,i.descr) from Item i", Item.class ).getSingleResult();
+		assertNotNull( itemView );
+		assertEquals( "Micro$oft mouse", itemView.getDescr() );
+		em.remove( item );
+		em.getTransaction().commit();
+
+		em.close();
+	}
+
 	@Override
 	public Class[] getAnnotatedClasses() {
 		return new Class[]{