HHH-11907 - Add the getResultStream() default method in org.hibernate.query.Query

hibernate-core/src/main/java/org/hibernate/query/Query.java

@@ -1109,4 +1109,15 @@ public interface Query<R> extends TypedQuery<R>, org.hibernate.Query<R>, CommonQ
 		return this;
 	}
 
+	/**
+	 * JPA 2.2 defines the {@code getResultStream} method so to get a {@link Stream} from the JDBC {@link java.sql.ResultSet}.
+	 *
+	 * Hibernate 5.2 already defines the {@link Query#stream()} method, so {@code getResultStream} can delegate to it.
+	 *
+	 * @return The results Stream
+	 * @since 5.2.11
+	 */
+	default Stream<R> getResultStream() {
+		return stream();
+	}
 }

hibernate-core/src/test/java/org/hibernate/test/stream/basic/JpaStreamTest.java

@@ -0,0 +1,81 @@
+/*
+ * 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.test.stream.basic;
+
+import java.util.stream.Stream;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.Table;
+import javax.persistence.Tuple;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Root;
+
+import org.hibernate.Session;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.engine.spi.SessionImplementor;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+import static org.hibernate.testing.junit4.ExtraAssertions.assertTyping;
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+
+/**
+ * @author Steve Ebersole
+ */
+public class JpaStreamTest extends BaseNonConfigCoreFunctionalTestCase {
+
+	@Override
+	protected Class[] getAnnotatedClasses() {
+		return new Class[] { MyEntity.class };
+	}
+
+	@Test
+	@TestForIssue(jiraKey = "HHH-11907")
+	public void testQueryStream() {
+		doInHibernate( this::sessionFactory, session -> {
+			MyEntity e= new MyEntity();
+			e.id = 1;
+			e.name = "Test";
+			session.persist( e );
+		} );
+
+		doInHibernate( this::sessionFactory, session -> {
+			// Test stream query without type.
+			Object result = session.createQuery( "From MyEntity" ).getResultStream().findFirst().orElse( null );
+			assertTyping( MyEntity.class, result );
+
+			// Test stream query with type.
+			result = session.createQuery( "From MyEntity", MyEntity.class ).getResultStream().findFirst().orElse( null );
+			assertTyping( MyEntity.class, result );
+
+			// Test stream query using forEach
+			session.createQuery( "From MyEntity", MyEntity.class ).getResultStream().forEach( i -> {
+				assertTyping( MyEntity.class, i );
+			} );
+
+			Stream<Object[]> data = session.createQuery( "SELECT me.id, me.name FROM MyEntity me" ).getResultStream();
+			data.forEach( i -> {
+				assertTyping( Integer.class, i[0] );
+				assertTyping( String.class, i[1] );
+			});
+		} );
+	}
+
+	@Entity(name = "MyEntity")
+	@Table(name="MyEntity")
+	public static class MyEntity {
+		@Id
+		public Integer id;
+		public String name;
+	}
+
+}