HHH-9637 : Join is reused when 2 explicit joins are used for the same ToOne association

(cherry picked from commit 6bb8d03595)

Conflicts:
	hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/metamodel/AbstractMetamodelSpecificTest.java

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

@@ -465,7 +465,7 @@ public class DotNode extends FromReferenceNode implements DisplayableNode, Selec
 
 		boolean found = elem != null;
 		// even though we might find a pre-existing element by join path, we may not be able to reuse it...
-		boolean useFoundFromElement = found && canReuse( elem );
+		boolean useFoundFromElement = found && canReuse( classAlias, elem );
 
 		if ( ! useFoundFromElement ) {
 			// If this is an implied join in a from element, then use the impled join type which is part of the
@@ -510,9 +510,10 @@ public class DotNode extends FromReferenceNode implements DisplayableNode, Selec
 		setFromElement( elem );	// This 'dot' expression now refers to the resulting from element.
 	}
 
-	private boolean canReuse(FromElement fromElement) {
+	private boolean canReuse(String classAlias, FromElement fromElement) {
 		// if the from-clauses are the same, we can be a little more aggressive in terms of what we reuse
-		if ( fromElement.getFromClause() == getWalker().getCurrentFromClause() ) {
+		if ( fromElement.getFromClause() == getWalker().getCurrentFromClause() &&
+				areSame( classAlias, fromElement.getClassAlias() )) {
 			return true;
 		}
 
@@ -520,6 +521,11 @@ public class DotNode extends FromReferenceNode implements DisplayableNode, Selec
 		return getWalker().getCurrentClauseType() != SqlTokenTypes.FROM;
 	}
 
+	private boolean areSame(String alias1, String alias2) {
+		// again, null != null here
+		return !StringHelper.isEmpty( alias1 ) && !StringHelper.isEmpty( alias2 ) && alias1.equals( alias2 );
+	}
+
 	private void setImpliedJoin(FromElement elem) {
 		this.impliedJoin = elem;
 		if ( getFirstChild().getType() == SqlTokenTypes.DOT ) {

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/Child.java

@@ -0,0 +1,80 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity1")
+public class Child {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+	@JoinColumn
+	private Set<GrandChild> grandChildren = new HashSet<GrandChild>();
+
+	public Child() {
+	}
+
+	public Child(String value) {
+		this.value = value;
+	}
+
+	private String value;
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public Set<GrandChild> getGrandChildren() {
+		return grandChildren;
+	}
+
+	public void setGrandChildren(Set<GrandChild> grandChildren) {
+		this.grandChildren = grandChildren;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/Entity1.java

@@ -0,0 +1,69 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity1")
+public class Entity1 {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	@ManyToOne
+	@JoinColumn(name="entity2_id", nullable = false)
+	private Entity2 entity2;
+
+	private String value;
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public Entity2 getEntity2() {
+		return entity2;
+	}
+
+	public void setEntity2(Entity2 entity2) {
+		this.entity2 = entity2;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/Entity2.java

@@ -0,0 +1,70 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity2")
+public class Entity2 {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name="entity3_id")
+	private Entity3 entity3;
+
+	private String value;
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public Entity3 getEntity3() {
+		return entity3;
+	}
+
+	public void setEntity3(Entity3 entity3) {
+		this.entity3 = entity3;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/Entity3.java

@@ -0,0 +1,56 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity3")
+public class Entity3 {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	private String value;
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/GrandChild.java

@@ -0,0 +1,65 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity1")
+public class GrandChild {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	private String value;
+
+	public GrandChild() {
+	}
+
+	public GrandChild(String value) {
+		this.value = value;
+	}
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/Parent.java

@@ -0,0 +1,80 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity1")
+public class Parent {
+	@Id
+	@GeneratedValue
+	private long id;
+
+	@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+	@JoinColumn
+	private Set<Child> children = new HashSet<Child>();
+
+	private String value;
+
+	public Parent() {
+	}
+
+	public Parent(String value) {
+		this.value = value;
+	}
+
+	public long getId() {
+		return id;
+	}
+
+	public void setId(long id) {
+		this.id = id;
+	}
+
+	public Set<Child> getChildren() {
+		return children;
+	}
+
+	public void setChildren(Set<Child> children) {
+		this.children = children;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/ToManyFetchAndJoinTest.java

@@ -0,0 +1,203 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import java.util.Iterator;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import org.hibernate.Hibernate;
+import org.hibernate.Session;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+/**
+ * @author Gail Badner
+ */
+public class ToManyFetchAndJoinTest extends BaseCoreFunctionalTestCase {
+
+	@Before
+	public void setupData() {
+		Parent p = new Parent( "p" );
+		Child c1 = new Child( "c1" );
+		GrandChild gc11 = new GrandChild( "gc11" );
+		GrandChild gc12 = new GrandChild( "gc12" );
+		p.getChildren().add( c1 );
+		c1.getGrandChildren().add( gc11 );
+		c1.getGrandChildren().add( gc12 );
+
+		Child c2 = new Child( "c2" );
+		GrandChild gc21 = new GrandChild( "gc21" );
+		GrandChild gc22 = new GrandChild( "gc22" );
+		GrandChild gc23 = new GrandChild( "gc23" );
+		p.getChildren().add( c2 );
+		c2.getGrandChildren().add( gc21 );
+		c2.getGrandChildren().add( gc22 );
+		c2.getGrandChildren().add( gc23 );
+
+		Session s = openSession();
+		s.getTransaction().begin();
+		s.persist( p );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@After
+	public void cleanupData() {
+		Session s = openSession();
+		s.getTransaction().begin();
+		s.createQuery( "delete Parent" ).executeUpdate();
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinBeforeFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Parent p =
+				(Parent) s.createQuery(
+						"select p from Parent p inner join p.children cRestrict inner join fetch p.children c inner join fetch c.grandChildren where cRestrict.value = 'c1'" )
+						.uniqueResult();
+
+		assertEquals( "p", p.getValue() );
+		assertTrue( Hibernate.isInitialized( p.getChildren() ) );
+		assertEquals( 2, p.getChildren().size() );
+		Iterator<Child> iterator = p.getChildren().iterator();
+		Child cA = iterator.next();
+		assertTrue( Hibernate.isInitialized( cA.getGrandChildren() ) );
+		if ( cA.getValue().equals( "c1" ) ) {
+			assertEquals( 2, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 3, cB.getGrandChildren().size() );
+		}
+		else if ( cA.getValue().equals( "c2" ) ) {
+			assertEquals( 3, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 2, cB.getGrandChildren().size() );
+		}
+		else {
+			fail( "unexpected value" );
+		}
+
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinBetweenFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Parent p =
+				(Parent) s.createQuery(
+						"select p from Parent p inner join fetch p.children c inner join p.children cRestrict inner join fetch c.grandChildren where cRestrict.value = 'c1'" )
+						.uniqueResult();
+
+		assertEquals( "p", p.getValue() );
+		assertTrue( Hibernate.isInitialized( p.getChildren() ) );
+		assertEquals( 2, p.getChildren().size() );
+		Iterator<Child> iterator = p.getChildren().iterator();
+		Child cA = iterator.next();
+		assertTrue( Hibernate.isInitialized( cA.getGrandChildren() ) );
+		if ( cA.getValue().equals( "c1" ) ) {
+			assertEquals( 2, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 3, cB.getGrandChildren().size() );
+		}
+		else if ( cA.getValue().equals( "c2" ) ) {
+			assertEquals( 3, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 2, cB.getGrandChildren().size() );
+		}
+		else {
+			fail( "unexpected value" );
+		}
+
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinAfterFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Parent p =
+				(Parent) s.createQuery(
+						"select p from Parent p inner join fetch p.children c inner join fetch c.grandChildren inner join p.children cRestrict where cRestrict.value = 'c1'" )
+						.uniqueResult();
+
+		assertEquals( "p", p.getValue() );
+		assertTrue( Hibernate.isInitialized( p.getChildren() ) );
+		assertEquals( 2, p.getChildren().size() );
+		Iterator<Child> iterator = p.getChildren().iterator();
+		Child cA = iterator.next();
+		assertTrue( Hibernate.isInitialized( cA.getGrandChildren() ) );
+		if ( cA.getValue().equals( "c1" ) ) {
+			assertEquals( 2, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 3, cB.getGrandChildren().size() );
+		}
+		else if ( cA.getValue().equals( "c2" ) ) {
+			assertEquals( 3, cA.getGrandChildren().size() );
+			Child cB = iterator.next();
+			assertTrue( Hibernate.isInitialized( cB.getGrandChildren() ) );
+			assertEquals( 2, cB.getGrandChildren().size() );
+		}
+		else {
+			fail( "unexpected value" );
+		}
+
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Override
+	protected Class[] getAnnotatedClasses() {
+		return new Class[]{
+				Parent.class,
+				Child.class,
+				GrandChild.class
+		};
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/hql/fetchAndJoin/ToOneFetchAndJoinTest.java

@@ -0,0 +1,159 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.test.hql.fetchAndJoin;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import org.hibernate.Hibernate;
+import org.hibernate.Session;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Gail Badner
+ */
+public class ToOneFetchAndJoinTest extends BaseCoreFunctionalTestCase {
+
+	@Before
+	public void setupData() {
+		Entity1 e1 = new Entity1();
+		e1.setValue( "entity1" );
+		Entity2 e2 = new Entity2();
+		e2.setValue( "entity2" );
+		Entity3 e3 = new Entity3();
+		e3.setValue( "entity3" );
+
+		e1.setEntity2( e2 );
+		e2.setEntity3( e3 );
+
+		Entity2 e2a = new Entity2();
+		e2a.setValue( "entity2a" );
+
+		Session s = openSession();
+		s.getTransaction().begin();
+		s.persist( e3 );
+		s.persist( e2 );
+		s.persist( e1 );
+		s.persist( e2a );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@After
+	public void cleanupData() {
+		Session s = openSession();
+		s.getTransaction().begin();
+		s.createQuery( "delete Entity1" ).executeUpdate();
+		s.createQuery( "delete Entity2" ).executeUpdate();
+		s.createQuery( "delete Entity3" ).executeUpdate();
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testFetchJoinsWithImplicitJoinInRestriction() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Entity1 e1Queryied =
+				(Entity1) s.createQuery(
+						"select e1 from Entity1 e1 inner join fetch e1.entity2 e2 inner join fetch e2.entity3 where e1.entity2.value = 'entity2'" )
+						.uniqueResult();
+		assertEquals( "entity1", e1Queryied.getValue() );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2() ) );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2().getEntity3() ) );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinBeforeFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Entity1 e1Queryied =
+				(Entity1) s.createQuery(
+						"select e1 from Entity1 e1 inner join e1.entity2 e1Restrict inner join fetch e1.entity2 e2 inner join fetch e2.entity3 where e1Restrict.value = 'entity2'" )
+						.uniqueResult();
+		assertEquals( "entity1", e1Queryied.getValue() );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2() ) );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2().getEntity3() ) );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinBetweenFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Entity1 e1Queryied =
+				(Entity1) s.createQuery(
+						"select e1 from Entity1 e1 inner join fetch e1.entity2 e2 inner join e1.entity2 e1Restrict inner join fetch e2.entity3 where e1Restrict.value = 'entity2'" )
+						.uniqueResult();
+		assertEquals( "entity1", e1Queryied.getValue() );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2() ) );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2().getEntity3() ) );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9637")
+	public void testExplicitJoinAfterFetchJoins() {
+
+		Session s = openSession();
+		s.getTransaction().begin();
+
+		Entity1 e1Queryied =
+				(Entity1) s.createQuery(
+						"select e1 from Entity1 e1 inner join fetch e1.entity2 e2 inner join fetch e2.entity3 inner join e1.entity2 e1Restrict where e1Restrict.value = 'entity2'" )
+						.uniqueResult();
+		assertEquals( "entity1", e1Queryied.getValue() );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2() ) );
+		assertTrue( Hibernate.isInitialized( e1Queryied.getEntity2().getEntity3() ) );
+		s.getTransaction().commit();
+		s.close();
+	}
+
+	@Override
+	protected Class[] getAnnotatedClasses() {
+		return new Class[]{
+				Entity1.class,
+				Entity2.class,
+				Entity3.class
+		};
+	}
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/criteria/paths/FetchAndJoinTest.java

@@ -0,0 +1,69 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.jpa.test.criteria.paths;
+
+import javax.persistence.EntityManager;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Fetch;
+import javax.persistence.criteria.Join;
+import javax.persistence.criteria.JoinType;
+import javax.persistence.criteria.Root;
+
+import org.junit.Test;
+
+import org.hibernate.jpa.test.metamodel.AbstractMetamodelSpecificTest;
+import org.hibernate.jpa.test.metamodel.Entity1;
+import org.hibernate.jpa.test.metamodel.Entity1_;
+import org.hibernate.jpa.test.metamodel.Entity2;
+import org.hibernate.jpa.test.metamodel.Entity2_;
+
+/**
+ * @author Gail Badner
+ */
+public class FetchAndJoinTest extends AbstractMetamodelSpecificTest {
+
+	@Test
+	public void testImplicitJoinFromExplicitCollectionJoin() {
+		EntityManager em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+
+		final CriteriaBuilder builder = em.getCriteriaBuilder();
+		final CriteriaQuery<Entity1> criteria = builder.createQuery(Entity1.class);
+
+		final Root<Entity1> root = criteria.from(Entity1.class);
+		final Join<Entity1, Entity2> entity2Join = root.join( Entity1_.entity2, JoinType.INNER); // illegal with fetch join
+
+		final Fetch<Entity1, Entity2> entity2Fetch = root.fetch(Entity1_.entity2, JoinType.INNER); // <=== REMOVE
+		entity2Fetch.fetch( Entity2_.entity3 ); // <=== REMOVE
+
+		criteria.where(builder.equal(root.get(Entity1_.value), "test"),
+				builder.equal(entity2Join.get(Entity2_.value), "test")); // illegal with fetch join
+
+		em.createQuery(criteria).getResultList();
+
+		em.getTransaction().commit();
+		em.close();
+	}
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/metamodel/Entity1.java

@@ -0,0 +1,43 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.jpa.test.metamodel;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity1")
+public class Entity1 {
+	@Id
+	private long id;
+
+	@ManyToOne
+	@JoinColumn(name="entity2_id", nullable = false)
+	private Entity2 entity2;
+
+	private String value;
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/metamodel/Entity2.java

@@ -0,0 +1,43 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.jpa.test.metamodel;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity2")
+public class Entity2 {
+	@Id
+	private long id;
+
+	@ManyToOne
+	@JoinColumn(name="entity3_id")
+	private Entity3 entity3;
+
+	private String value;
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/metamodel/Entity3.java

@@ -0,0 +1,37 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, 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 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
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.jpa.test.metamodel;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "entity3")
+public class Entity3 {
+	@Id
+	private long id;
+
+	private String value;
+}