[master] Clone batchQuery to allow for proper nested lazy instantiation

foundation/org.eclipse.persistence.core/src/main/java/org/eclipse/persistence/mappings/ForeignReferenceMapping.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2024 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2025 Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2020 IBM Corporation. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
@@ -645,7 +645,11 @@ public Object extractResultFromBatchQuery(ReadQuery batchQuery, CacheKey parentC
             } else if (batchQuery.isReadAllQuery() && ((ReadAllQuery)batchQuery).getBatchFetchPolicy().isIN()) {
                 throw QueryException.originalQueryMustUseBatchIN(this, originalQuery);
             }
-            executeBatchQuery(batchQuery, parentCacheKey, batchedObjects, session, translationRow);
+            // Execute each batch as a separate query so that nested batch relationships are not overwritten by the most
+            // recent batch fetched Issue #1998
+            ReadQuery batchQueryToExecute = (ReadQuery) batchQuery.clone();
+            executeBatchQuery(batchQueryToExecute, parentCacheKey, batchedObjects, session, translationRow);
+            batchQueryToExecute.setSession(null);
             batchQuery.setSession(null);
         }
         result = batchedObjects.get(sourceKey);

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/main/java/org/eclipse/persistence/testing/models/jpa/batchfetch/BatchFetchCacheTableCreator.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2025 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ */
+
+// Contributors:
+
+package org.eclipse.persistence.testing.models.jpa.batchfetch;
+
+import org.eclipse.persistence.tools.schemaframework.FieldDefinition;
+import org.eclipse.persistence.tools.schemaframework.TableCreator;
+import org.eclipse.persistence.tools.schemaframework.TableDefinition;
+
+public class BatchFetchCacheTableCreator extends TableCreator {
+    public BatchFetchCacheTableCreator() {
+        setName("BatchFetchCacheProject");
+
+        addTableDefinition(buildParentTable());
+        addTableDefinition(buildChildTable());
+    }
+
+    public TableDefinition buildParentTable() {
+        TableDefinition table = new TableDefinition();
+        table.setName("BATCH_IN_CACHE_PARENT");
+
+        FieldDefinition fieldID = new FieldDefinition();
+        fieldID.setName("ID");
+        fieldID.setTypeName("NUMBER");
+        fieldID.setSize(19);
+        fieldID.setSubSize(0);
+        fieldID.setIsPrimaryKey(true);
+        fieldID.setIsIdentity(true);
+        fieldID.setShouldAllowNull(false);
+        table.addField(fieldID);
+
+        return table;
+    }
+
+
+    public TableDefinition buildChildTable() {
+        TableDefinition table = new TableDefinition();
+        table.setName("BATCH_IN_CACHE_CHILD");
+
+        FieldDefinition fieldID = new FieldDefinition();
+        fieldID.setName("ID");
+        fieldID.setTypeName("NUMBER");
+        fieldID.setSize(19);
+        fieldID.setSubSize(0);
+        fieldID.setIsPrimaryKey(true);
+        fieldID.setIsIdentity(true);
+        fieldID.setShouldAllowNull(false);
+        table.addField(fieldID);
+
+        FieldDefinition fieldParent = new FieldDefinition();
+        fieldParent.setName("PARENT_ID");
+        fieldParent.setTypeName("NUMBER");
+        fieldParent.setSize(19);
+        fieldParent.setSubSize(0);
+        fieldParent.setIsPrimaryKey(false);
+        fieldParent.setIsIdentity(false);
+        fieldParent.setShouldAllowNull(false);
+        fieldParent.setForeignKeyFieldName("BATCH_IN_CACHE_PARENT.ID");
+        table.addField(fieldParent);
+
+        return table;
+
+    }
+
+}

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/main/java/org/eclipse/persistence/testing/models/jpa/batchfetch/Child.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2025 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ */
+
+// Contributors:
+
+package org.eclipse.persistence.testing.models.jpa.batchfetch;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import org.eclipse.persistence.annotations.BatchFetch;
+import org.eclipse.persistence.annotations.BatchFetchType;
+
+@Entity
+@Table(name = "BATCH_IN_CACHE_CHILD")
+public class Child {
+    @Id
+    @GeneratedValue
+    private long id;
+
+    @ManyToOne
+    @JoinColumn(name = "PARENT_ID")
+    @BatchFetch(value = BatchFetchType.IN)
+    private Parent parent;
+
+    public Child() {
+    }
+
+    public Child(long id, Parent parent) {
+        this.id = id;
+        this.parent = parent;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public Parent getParent() {
+        return parent;
+    }
+
+    public void setParent(Parent parent) {
+        this.parent = parent;
+    }
+}

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/main/java/org/eclipse/persistence/testing/models/jpa/batchfetch/Parent.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2025 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ */
+
+// Contributors:
+
+package org.eclipse.persistence.testing.models.jpa.batchfetch;
+
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.Table;
+import org.eclipse.persistence.annotations.BatchFetch;
+import org.eclipse.persistence.annotations.BatchFetchType;
+import org.eclipse.persistence.annotations.CascadeOnDelete;
+
+import java.util.Collection;
+
+@Entity
+@Table(name = "BATCH_IN_CACHE_PARENT")
+public class Parent {
+    @Id
+    @GeneratedValue
+    private long id;
+
+    @OneToMany(mappedBy = "parent")
+    @BatchFetch(value = BatchFetchType.IN)
+    private Collection<Child> children;
+
+    public Parent() {
+    }
+
+    public Parent(long id) {
+        this.id = id;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public Collection<Child> getChildren() {
+        return children;
+    }
+
+    public void setChildren(Collection<Child> children) {
+        this.children = children;
+    }
+}

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/main/resources/META-INF/persistence.xml

@@ -1,6 +1,6 @@
 <!--
 
-    Copyright (c) 2024 Oracle and/or its affiliates. All rights reserved.
+    Copyright (c) 2024, 2025 Oracle and/or its affiliates. All rights reserved.
 
     This program and the accompanying materials are made available under the
     terms of the Eclipse Public License v. 2.0 which is available at
@@ -20,6 +20,8 @@
 		<class>org.eclipse.persistence.testing.models.jpa.batchfetch.Company</class>
 		<class>org.eclipse.persistence.testing.models.jpa.batchfetch.Employee</class>
 		<class>org.eclipse.persistence.testing.models.jpa.batchfetch.Record</class>
+		<class>org.eclipse.persistence.testing.models.jpa.batchfetch.Child</class>
+		<class>org.eclipse.persistence.testing.models.jpa.batchfetch.Parent</class>
 		<properties>
 			<property name="eclipselink.logging.level" value="${eclipselink.logging.level}"/>
 			<property name="eclipselink.logging.level.sql" value="${eclipselink.logging.sql.level}"/>

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/test/java/org/eclipse/persistence/testing/tests/jpa/batchfetch/BatchFetchCacheJUnitTest.java

@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 1998, 2025 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ */
+
+// Contributors:
+
+package org.eclipse.persistence.testing.tests.jpa.batchfetch;
+
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.TypedQuery;
+import junit.framework.Test;
+import junit.framework.TestSuite;
+import org.eclipse.persistence.config.QueryHints;
+import org.eclipse.persistence.testing.framework.jpa.junit.JUnitTestCase;
+import org.eclipse.persistence.testing.models.jpa.batchfetch.BatchFetchCacheTableCreator;
+import org.eclipse.persistence.testing.models.jpa.batchfetch.Child;
+import org.eclipse.persistence.testing.models.jpa.batchfetch.Parent;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Objects;
+
+public class BatchFetchCacheJUnitTest extends JUnitTestCase {
+
+    public BatchFetchCacheJUnitTest() {
+        super();
+    }
+
+    public BatchFetchCacheJUnitTest(String name) {
+        super(name);
+    }
+
+    public static Test suite() {
+        TestSuite suite = new TestSuite();
+        suite.setName("BatchFetchCacheJunitTest");
+        suite.addTest(new BatchFetchCacheJUnitTest("testSetup"));
+        suite.addTest(new BatchFetchCacheJUnitTest("testSelectChildren"));
+        return suite;
+    }
+
+    /**
+     * The setup is done as a test, both to record its failure, and to allow execution in the server.
+     */
+    public void testSetup() {
+        new BatchFetchCacheTableCreator().replaceTables(JUnitTestCase.getServerSession(
+                getPersistenceUnitName()));
+        EntityManager em = createEntityManager();
+        createRecords(em);
+    }
+
+    public void createRecords(EntityManager em) {
+        try {
+            beginTransaction(em);
+            Parent p1 = new Parent(1);
+            Parent p2 = new Parent(2);
+            Parent p3 = new Parent(3);
+            em.persist(p1);
+            em.persist(p2);
+            em.persist(p3);
+
+            Child u1 = new Child(1, p1);
+            Child u2 = new Child(2, p2);
+            Child u3 = new Child(3, p3);
+            em.persist(u1);
+            em.persist(u2);
+            em.persist(u3);
+
+            commitTransaction(em);
+        } catch (RuntimeException ex) {
+            if (isTransactionActive(em)) {
+                rollbackTransaction(em);
+            }
+            throw ex;
+        } finally {
+            closeEntityManager(em);
+        }
+    }
+
+    public void testSelectChildren() {
+        EntityManager em = createEntityManager();
+        em.getEntityManagerFactory().getCache().evictAll();
+
+        try {
+            TypedQuery<Child> q = em.createQuery("SELECT c FROM Child c", Child.class);
+            q.setHint(QueryHints.BATCH_SIZE, 1);
+            List<Child> result = q.getResultList();
+            assertEquals("Not all rows are selected", 3, result.size());
+            List<Parent> parents = result.stream().map(Child::getParent).filter(Objects::nonNull).toList();
+            assertEquals("Not all rows have parents", 3, parents.size());
+            List<Child> childrenOfParents = parents.stream()
+                                                   .map(Parent::getChildren)
+                                                   .flatMap(Collection::stream)
+                                                   .filter(Objects::nonNull)
+                                                   .toList();
+            assertEquals("Not all parents have children", 3, childrenOfParents.size());
+        } catch (RuntimeException e) {
+            closeEntityManager(em);
+            throw e;
+        }
+    }
+
+    @Override
+    public String getPersistenceUnitName() {
+        return "batchfetch";
+    }
+}

jpa/eclipselink.jpa.testapps/jpa.test.batchfetch/src/test/java/org/eclipse/persistence/testing/tests/jpa/batchfetch/BatchFetchJUnitTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2024 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2025 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
@@ -54,7 +54,7 @@ public static Test suite() {
      */
     public void testSetup() {
         new BatchFetchTableCreator().replaceTables(JUnitTestCase.getServerSession(
-                "batchfetch"));
+                getPersistenceUnitName()));
         EntityManager em = createEntityManager();
         createRecords(em);
     }