OPENJPA-925 Bidirectional OneToOne relation incorrectly set in loadEagerJoin

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@745408 13f79535-47bb-0310-9956-ffa450edef68

openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/meta/strats/RelationFieldStrategy.java

@@ -644,8 +644,11 @@ public class RelationFieldStrategy
         if (mappedByFieldMapping != null) {
         	ValueMapping val = mappedByFieldMapping.getValueMapping();
         	ClassMetaData decMeta = val.getTypeMetaData();
-        	// this inverse field does not have corresponding classMapping
+            // eager loading a child from its toOne parent and
-        	// its value may be a collection/map etc.
+            // the parent has @OneToOne(mappedBy="parent") child relation.
+            // By saving the mapped-by info in 'res' is to
+            // avoid unneeded SQL pushdown that would otherwise gets
+            // generated.
             if (decMeta != null) {
         	    mappedByValue = sm.getPersistenceCapable();
         	    res.setMappedByFieldMapping(mappedByFieldMapping);
@@ -655,6 +658,12 @@ public class RelationFieldStrategy
 
         sm.storeObject(field.getIndex(), res.load(cls, store, fetch,
             eagerJoin(res.newJoins(), cls, false)));
+
+        // reset mapped by is needed for OneToOne bidirectional relations
+        // having a mapped-by parent to correctly set the parent-child
+        // relation.
+        res.setMappedByFieldMapping(null);
+        res.setMappedByValue(null);
     }
 
     public void load(OpenJPAStateManager sm, JDBCStore store,

openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/relations/OneOneChild.java

@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.openjpa.persistence.relations;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.OneToOne;
+import javax.persistence.Version;
+
+@Entity
+public class OneOneChild {
+
+    @Id
+    @GeneratedValue
+    private long id;
+
+    private String name;
+
+    @OneToOne
+    private OneOneParent parent;
+
+    @Version
+    private Integer optLock;
+
+    public long getId() { 
+        return id; 
+    }
+
+    public String getName() { 
+        return name; 
+    }
+
+    public void setName(String name) { 
+        this.name = name; 
+    }
+
+    public OneOneParent getParent() { 
+        return parent; 
+    }
+
+    public void setParent(OneOneParent parent) { 
+        this.parent = parent; 
+    }
+}

openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/relations/OneOneParent.java

@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.openjpa.persistence.relations;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.OneToOne;
+import javax.persistence.Version;
+
+@Entity
+public class OneOneParent {
+
+    @Id
+    @GeneratedValue
+    private long id;
+
+    private String name;
+
+    @OneToOne(mappedBy="parent")
+    private OneOneChild child;
+
+    @Version
+    private Integer optLock;
+
+    public long getId() { 
+        return id; 
+    }
+
+    public String getName() { 
+        return name; 
+    }
+
+    public void setName(String name) { 
+        this.name = name; 
+    }
+
+    public OneOneChild getChild() { 
+        return child; 
+    }
+
+    public void setChild(OneOneChild child) { 
+        this.child = child; 
+    }
+}

openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/relations/TestManyEagerSQL.java

@@ -35,7 +35,8 @@ public class TestManyEagerSQL
     public void setUp() {
         setUp(
             OneManyEagerParent.class, OneManyEagerChild.class,
-            OneManyLazyChild.class);
+            OneManyLazyChild.class, OneOneParent.class, 
+            OneOneChild.class);
         
         EntityManager em = emf.createEntityManager();
         em.getTransaction().begin();
@@ -56,6 +57,17 @@ public class TestManyEagerSQL
             em.persist(parent);
         }
         
+        for (int i = 0; i < 3; i++) {
+        	OneOneParent parent = new OneOneParent();
+        	parent.setName("parent" + i);
+        	OneOneChild child = new OneOneChild();
+        	child.setName("child" + i);
+        	parent.setChild(child);
+        	child.setParent(parent);
+        	em.persist(child);
+        	em.persist(parent);
+        }
+        
         em.flush();
         em.getTransaction().commit();
         em.close();
@@ -190,6 +202,59 @@ public class TestManyEagerSQL
         em.close();
     }
 
+    public void testOneToOneParentQuery() {
+        sql.clear();
+
+        OpenJPAEntityManager em = emf.createEntityManager();
+        String query = "select p FROM OneOneParent p";
+        Query q = em.createQuery(query);
+        List list = q.getResultList();
+        assertEquals(3, list.size());
+
+        // Expected SQLs:
+        //   SELECT t0.id, t0.optLock, t1.id, t1.optLock, t1.name, t2.id, 
+        //   t2.optLock, t2.CHILD_ID, t2.name, t0.name 
+        //       FROM OneOneParent t0 
+        //       LEFT OUTER JOIN OneOneChild t1 ON t0.CHILD_ID = t1.id 
+        //       LEFT OUTER JOIN OneOneParent t2 ON t1.PARENT_ID = t2.id
+
+        assertEquals(1, sql.size());
+
+        sql.clear();
+
+        for (int i = 0; i < list.size(); i++) {
+            OneOneParent p = (OneOneParent) list.get(i);
+            assertEquals(p, p.getChild().getParent());
+        }
+
+        assertEquals(0, sql.size());
+        em.close();
+    }
+
+    public void testOneToOneChildQuery() {
+        sql.clear();
+
+        OpenJPAEntityManager em = emf.createEntityManager();
+        String query = "select c FROM OneOneChild c";
+        Query q = em.createQuery(query);
+        List list = q.getResultList();
+        assertEquals(3, list.size());
+
+        // Expected SQLs:
+
+        assertEquals(1, sql.size());
+
+        sql.clear();
+
+        for (int i = 0; i < list.size(); i++) {
+            OneOneChild c = (OneOneChild) list.get(i);
+            assertEquals(c, c.getParent().getChild());
+        }
+
+        assertEquals(0, sql.size());
+        em.close();
+    }
+
     public static void main(String[] args) {
         TestRunner.run(TestManyEagerSQL.class);
     }