HHH-16710 allow Map and List instantiation for native SQL queries

hibernate-core/src/main/java/org/hibernate/internal/AbstractSharedSessionContract.java

@@ -12,6 +12,7 @@ import java.io.ObjectOutputStream;
 import java.sql.SQLException;
 import java.util.List;
 import java.util.Locale;
+import java.util.Map;
 import java.util.TimeZone;
 import java.util.UUID;
 import java.util.function.Function;
@@ -44,6 +45,8 @@ import org.hibernate.id.uuid.StandardRandomStrategy;
 import org.hibernate.jdbc.ReturningWork;
 import org.hibernate.jdbc.Work;
 import org.hibernate.jdbc.WorkExecutorVisitable;
+import org.hibernate.jpa.spi.NativeQueryListTransformer;
+import org.hibernate.jpa.spi.NativeQueryMapTransformer;
 import org.hibernate.jpa.spi.NativeQueryTupleTransformer;
 import org.hibernate.persister.entity.EntityPersister;
 import org.hibernate.procedure.ProcedureCall;
@@ -849,7 +852,12 @@ public abstract class AbstractSharedSessionContract implements SharedSessionCont
 		if ( Tuple.class.equals( resultClass ) ) {
 			query.setTupleTransformer( new NativeQueryTupleTransformer() );
 		}
-		// TODO: handle Map, List as well
+		else if ( Map.class.equals( resultClass ) ) {
+			query.setTupleTransformer( new NativeQueryMapTransformer() );
+		}
+		else if ( List.class.equals( resultClass ) ) {
+			query.setTupleTransformer( new NativeQueryListTransformer() );
+		}
 		else if ( getFactory().getMappingMetamodel().isEntityClass( resultClass ) ) {
 			query.addEntity( "alias1", resultClass.getName(), LockMode.READ );
 		}

hibernate-core/src/main/java/org/hibernate/jpa/spi/NativeQueryListTransformer.java

@@ -0,0 +1,23 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.jpa.spi;
+
+import org.hibernate.query.TupleTransformer;
+
+import java.util.List;
+
+/**
+ * A {@link TupleTransformer} for handling {@link List} results from native queries.
+ *
+ * @author Gavin King
+ */
+public class NativeQueryListTransformer implements TupleTransformer<List<Object>> {
+	@Override
+	public List<Object> transformTuple(Object[] tuple, String[] aliases) {
+		return List.of( tuple );
+	}
+}

hibernate-core/src/main/java/org/hibernate/jpa/spi/NativeQueryMapTransformer.java

@@ -0,0 +1,30 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.jpa.spi;
+
+import org.hibernate.query.TupleTransformer;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static java.util.Locale.ROOT;
+
+/**
+ * A {@link TupleTransformer} for handling {@link Map} results from native queries.
+ *
+ * @author Gavin King
+ */
+public class NativeQueryMapTransformer implements TupleTransformer<Map<String,Object>> {
+	@Override
+	public Map<String,Object> transformTuple(Object[] tuple, String[] aliases) {
+		Map<String,Object> map = new HashMap<>( aliases.length );
+		for ( int i = 0; i < aliases.length; i++ ) {
+			map.put( aliases[i].toLowerCase(ROOT), tuple[i] );
+		}
+		return map;
+	}
+}

hibernate-core/src/main/java/org/hibernate/jpa/spi/NativeQueryTupleTransformer.java

@@ -18,6 +18,8 @@ import org.hibernate.HibernateException;
 import org.hibernate.query.TypedTupleTransformer;
 import org.hibernate.transform.ResultTransformer;
 
+import static java.util.Locale.ROOT;
+
 /**
  * A {@link ResultTransformer} for handling JPA {@link Tuple} results from native queries.
  *
@@ -81,7 +83,7 @@ public class NativeQueryTupleTransformer implements ResultTransformer<Tuple>, Ty
 				final String alias = aliases[i];
 				if ( alias != null ) {
 					aliasToValue.put( alias, tuple[i] );
-					aliasReferences.put( alias.toLowerCase(), alias );
+					aliasReferences.put( alias.toLowerCase(ROOT), alias );
 				}
 			}
 			size = tuple.length;
@@ -96,7 +98,7 @@ public class NativeQueryTupleTransformer implements ResultTransformer<Tuple>, Ty
 
 		@Override
 		public Object get(String alias) {
-			final String aliasReference = aliasReferences.get( alias.toLowerCase() );
+			final String aliasReference = aliasReferences.get( alias.toLowerCase(ROOT) );
 			if ( aliasReference != null && aliasToValue.containsKey( aliasReference ) ) {
 				return aliasToValue.get( aliasReference );
 			}

hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ImplicitInstantiationTest.java

@@ -128,6 +128,52 @@ public class ImplicitInstantiationTest {
 		);
 	}
 
+	@Test
+	public void testSqlTupleInstantiationWithAlias(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.persist(new Thing(1L, "thing"));
+					Tuple result = session.createNativeQuery("select id as id, upper(name) as name from thingy_table", Tuple.class)
+							.addSynchronizedEntityClass(Thing.class)
+							.getSingleResult();
+					assertEquals( result.get("id"), 1L );
+					assertEquals( result.get("name"), "THING" );
+					session.getTransaction().setRollbackOnly();
+				}
+		);
+	}
+
+	@Test
+	public void testSqlMapInstantiationWithAlias(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.persist(new Thing(1L, "thing"));
+					Map result = session.createNativeQuery("select id as id, upper(name) as name from thingy_table", Map.class)
+							.addSynchronizedEntityClass(Thing.class)
+							.getSingleResult();
+					assertEquals( result.get("id"), 1L );
+					assertEquals( result.get("name"), "THING" );
+					session.getTransaction().setRollbackOnly();
+				}
+		);
+	}
+
+	@Test
+	public void testSqlListInstantiationWithoutAlias(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.persist(new Thing(1L, "thing"));
+					List result = session.createNativeQuery("select id as id, upper(name) as name from thingy_table", List.class)
+							.addSynchronizedEntityClass(Thing.class)
+							.getSingleResult();
+					assertEquals( result.get(0), 1L );
+					assertEquals( result.get(1), "THING" );
+					session.getTransaction().setRollbackOnly();
+				}
+		);
+	}
+
+
 	@Entity(name = "Thing")
 	@Table(name = "thingy_table")
 	public class Thing {