HHH-4073 - Discriminator formula support in Envers

hibernate-envers/src/main/java/org/hibernate/envers/configuration/metadata/AuditMetadataGenerator.java

@@ -66,6 +66,7 @@
  * @author Tomasz Bech
  * @author Stephanie Pau at Markit Group Plc
  * @author Hernán Chanfreau
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
  */
 public final class AuditMetadataGenerator {
     private static final Logger log = LoggerFactory.getLogger(AuditMetadataGenerator.class);
@@ -332,7 +333,8 @@ private Triple<Element, ExtendedPropertyMapper, String> generateMappingData(
         // Checking if there is a discriminator column
         if (pc.getDiscriminator() != null) {
             Element discriminator_element = class_mapping.addElement("discriminator");
-            MetadataTools.addColumns(discriminator_element, pc.getDiscriminator().getColumnIterator());
+            // Database column or SQL formula allowed to distinguish entity types
+            MetadataTools.addColumnsOrFormulas(discriminator_element, pc.getDiscriminator().getColumnIterator());
             discriminator_element.addAttribute("type", pc.getDiscriminator().getType().getName());
         }
 

hibernate-envers/src/main/java/org/hibernate/envers/configuration/metadata/MetadataTools.java

@@ -32,9 +32,11 @@
 import org.hibernate.envers.tools.StringTools;
 
 import org.hibernate.mapping.Column;
+import org.hibernate.mapping.Formula;
 
 /**
  * @author Adam Warski (adam at warski dot org)
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
  */
 public class MetadataTools {
     public static Element addNativelyGeneratedId(Element parent, String name, String type) {
@@ -185,11 +187,21 @@ public static Element createJoin(Element parent, String tableName,
 
     public static void addColumns(Element any_mapping, Iterator<Column> columns) {
         while (columns.hasNext()) {
-            Column column = columns.next();
+            addColumn(any_mapping, columns.next());
+        }
+    }
+
+    /**
+     * Adds <code>column</code> element with the following attributes (unless empty): <code>name</code>,
+     * <code>length</code>, <code>scale</code>, <code>precision</code>, <code>sql-type</code>, <code>read</code>
+     * and <code>write</code>.
+     * @param any_mapping Parent element.
+     * @param column Column descriptor.
+     */
+    public static void addColumn(Element any_mapping, Column column) {
         addColumn(any_mapping, column.getName(), column.getLength(), column.getScale(), column.getPrecision(),
                   column.getSqlType(), column.getCustomRead(), column.getCustomWrite());
     }
-    }
 
     @SuppressWarnings({"unchecked"})
     private static void changeNamesInColumnElement(Element element, ColumnNameIterator columnNameIterator) {
@@ -231,6 +243,32 @@ public static void prefixNamesInPropertyElement(Element element, String prefix,
         }
     }
 
+    /**
+     * Adds <code>formula</code> element.
+     * @param element Parent element.
+     * @param formula Formula descriptor.
+     */
+    public static void addFormula(Element element, Formula formula) {
+        element.addElement("formula").setText(formula.getText());
+    }
+
+    /**
+     * Adds all <code>column</code> or <code>formula</code> elements.
+     * @param element Parent element.
+     * @param columnIterator Iterator pointing at {@link org.hibernate.mapping.Column} and/or
+     *                       {@link org.hibernate.mapping.Formula} objects.
+     */
+    public static void addColumnsOrFormulas(Element element, Iterator columnIterator) {
+        while (columnIterator.hasNext()) {
+            Object o = columnIterator.next();
+            if (o instanceof Column) {
+                addColumn(element, (Column) o);
+            } else if (o instanceof Formula) {
+                addFormula(element, (Formula) o);
+            }
+        }
+    }
+
     /**
      * An iterator over column names.
      */

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/inheritance/single/discriminatorformula/ChildEntity.java

@@ -0,0 +1,59 @@
+package org.hibernate.envers.test.integration.inheritance.single.discriminatorformula;
+
+import org.hibernate.envers.Audited;
+
+import javax.persistence.DiscriminatorValue;
+import javax.persistence.Entity;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Entity
+@DiscriminatorValue(ClassTypeEntity.CHILD_TYPE)
+@Audited
+public class ChildEntity extends ParentEntity {
+    private String specificData;
+
+    public ChildEntity() {
+    }
+
+    public ChildEntity(Long typeId, String data, String specificData) {
+        super(typeId, data);
+        this.specificData = specificData;
+    }
+
+    public ChildEntity(Long id, Long typeId, String data, String specificData) {
+        super(id, typeId, data);
+        this.specificData = specificData;
+    }
+
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof ChildEntity)) return false;
+        if (!super.equals(o)) return false;
+
+        ChildEntity that = (ChildEntity) o;
+
+        if (specificData != null ? !specificData.equals(that.specificData) : that.specificData != null) return false;
+
+        return true;
+    }
+
+    public int hashCode() {
+        int result = super.hashCode();
+        result = 31 * result + (specificData != null ? specificData.hashCode() : 0);
+        return result;
+    }
+
+    public String toString() {
+        return "ChildEntity(id = " + id + ", typeId = " + typeId + ", data = " + data + ", specificData = " + specificData + ")";
+    }
+
+    public String getSpecificData() {
+        return specificData;
+    }
+
+    public void setSpecificData(String specificData) {
+        this.specificData = specificData;
+    }
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/inheritance/single/discriminatorformula/ClassTypeEntity.java

@@ -0,0 +1,59 @@
+package org.hibernate.envers.test.integration.inheritance.single.discriminatorformula;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Entity
+public class ClassTypeEntity {
+    public static final String PARENT_TYPE = "Parent";
+    public static final String CHILD_TYPE = "Child";
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String type;
+
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof ClassTypeEntity)) return false;
+
+        ClassTypeEntity that = (ClassTypeEntity) o;
+
+        if (id != null ? !id.equals(that.id) : that.id != null) return false;
+        if (type != null ? !type.equals(that.type) : that.type != null) return false;
+
+        return true;
+    }
+
+    public int hashCode() {
+        int result = super.hashCode();
+        result = 31 * result + (id != null ? id.hashCode() : 0);
+        result = 31 * result + (type != null ? type.hashCode() : 0);
+        return result;
+    }
+
+    public String toString() {
+        return "ClassTypeEntity(id = " + id + ", type = " + type + ")";
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/inheritance/single/discriminatorformula/DiscriminatorFormulaTest.java

@@ -0,0 +1,131 @@
+package org.hibernate.envers.test.integration.inheritance.single.discriminatorformula;
+
+import org.hibernate.ejb.Ejb3Configuration;
+import org.hibernate.envers.test.AbstractEntityTest;
+import org.hibernate.envers.test.Priority;
+import org.hibernate.mapping.Formula;
+import org.hibernate.mapping.PersistentClass;
+import org.junit.Test;
+
+import javax.persistence.EntityManager;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+public class DiscriminatorFormulaTest extends AbstractEntityTest {
+    private PersistentClass parentAudit = null;
+    private ChildEntity childVer1 = null;
+    private ChildEntity childVer2 = null;
+    private ParentEntity parentVer1 = null;
+    private ParentEntity parentVer2 = null;
+
+    @Override
+    public void configure(Ejb3Configuration cfg) {
+        cfg.addAnnotatedClass(ClassTypeEntity.class);
+        cfg.addAnnotatedClass(ParentEntity.class);
+        cfg.addAnnotatedClass(ChildEntity.class);
+    }
+
+    @Test
+    @Priority(10)
+    public void initData() {
+        parentAudit = getCfg().getClassMapping("org.hibernate.envers.test.integration.inheritance.single.discriminatorformula.ParentEntity_AUD");
+
+        EntityManager em = getEntityManager();
+
+        // Child entity type
+        em.getTransaction().begin();
+        ClassTypeEntity childType = new ClassTypeEntity();
+        childType.setType(ClassTypeEntity.CHILD_TYPE);
+        em.persist(childType);
+        Long childTypeId = childType.getId();
+        em.getTransaction().commit();
+
+        // Parent entity type
+        em.getTransaction().begin();
+        ClassTypeEntity parentType = new ClassTypeEntity();
+        parentType.setType(ClassTypeEntity.PARENT_TYPE);
+        em.persist(parentType);
+        Long parentTypeId = parentType.getId();
+        em.getTransaction().commit();
+
+        // Child Rev 1
+        em.getTransaction().begin();
+        ChildEntity child = new ChildEntity(childTypeId, "Child data", "Child specific data");
+        em.persist(child);
+        Long childId = child.getId();
+        em.getTransaction().commit();
+
+        // Parent Rev 2
+        em.getTransaction().begin();
+        ParentEntity parent = new ParentEntity(parentTypeId, "Parent data");
+        em.persist(parent);
+        Long parentId = parent.getId();
+        em.getTransaction().commit();
+
+        // Child Rev 3
+        em.getTransaction().begin();
+        child = em.find(ChildEntity.class, childId);
+        child.setData("Child data modified");
+        em.getTransaction().commit();
+
+        // Parent Rev 4
+        em.getTransaction().begin();
+        parent = em.find(ParentEntity.class, parentId);
+        parent.setData("Parent data modified");
+        em.getTransaction().commit();
+
+        childVer1 = new ChildEntity(childId, childTypeId, "Child data", "Child specific data");
+        childVer2 = new ChildEntity(childId, childTypeId, "Child data modified", "Child specific data");
+        parentVer1 = new ParentEntity(parentId, parentTypeId, "Parent data");
+        parentVer2 = new ParentEntity(parentId, parentTypeId, "Parent data modified");
+    }
+
+    @Test
+    public void testDiscriminatorFormulaInAuditTable() {
+        assert parentAudit.getDiscriminator().hasFormula();
+        Iterator iterator = parentAudit.getDiscriminator().getColumnIterator();
+        while (iterator.hasNext()) {
+            Object o = iterator.next();
+            if (o instanceof Formula) {
+                Formula formula = (Formula) o;
+                assert formula.getText().equals(ParentEntity.DISCRIMINATOR_QUERY);
+                return;
+            }
+        }
+        assert false;
+    }
+
+    @Test
+    public void testRevisionsCounts() {
+        assert Arrays.asList(1, 3).equals(getAuditReader().getRevisions(ChildEntity.class, childVer1.getId()));
+        assert Arrays.asList(2, 4).equals(getAuditReader().getRevisions(ParentEntity.class, parentVer1.getId()));
+    }
+
+    @Test
+    public void testHistoryOfParent() {
+        assert getAuditReader().find(ParentEntity.class, parentVer1.getId(), 2).equals(parentVer1);
+        assert getAuditReader().find(ParentEntity.class, parentVer2.getId(), 4).equals(parentVer2);
+    }
+
+    @Test
+    public void testHistoryOfChild() {
+        assert getAuditReader().find(ChildEntity.class, childVer1.getId(), 1).equals(childVer1);
+        assert getAuditReader().find(ChildEntity.class, childVer2.getId(), 3).equals(childVer2);
+    }
+
+    @Test
+    public void testPolymorphicQuery() {
+        assert getAuditReader().createQuery().forEntitiesAtRevision(ChildEntity.class, 1).getSingleResult().equals(childVer1);
+        assert getAuditReader().createQuery().forEntitiesAtRevision(ParentEntity.class, 1).getSingleResult().equals(childVer1);
+
+        List childEntityRevisions = getAuditReader().createQuery().forRevisionsOfEntity(ChildEntity.class, true, false).getResultList();
+        assert Arrays.asList(childVer1, childVer2).equals(childEntityRevisions);
+
+        List parentEntityRevisions = getAuditReader().createQuery().forRevisionsOfEntity(ParentEntity.class, true, false).getResultList();
+        assert Arrays.asList(childVer1, parentVer1, childVer2, parentVer2).equals(parentEntityRevisions);
+    }
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/inheritance/single/discriminatorformula/ParentEntity.java

@@ -0,0 +1,91 @@
+package org.hibernate.envers.test.integration.inheritance.single.discriminatorformula;
+
+import org.hibernate.annotations.DiscriminatorFormula;
+import org.hibernate.envers.Audited;
+
+import javax.persistence.DiscriminatorValue;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+@Entity
+@DiscriminatorFormula(ParentEntity.DISCRIMINATOR_QUERY)
+@DiscriminatorValue(ClassTypeEntity.PARENT_TYPE)
+@Audited
+public class ParentEntity {
+    public static final String DISCRIMINATOR_QUERY = "(SELECT c.type FROM ClassTypeEntity c WHERE c.id = typeId)";
+
+    @Id
+    @GeneratedValue
+    protected Long id;
+
+    protected Long typeId;
+
+    protected String data;
+
+    public ParentEntity() {
+    }
+
+    public ParentEntity(Long typeId, String data) {
+        this.typeId = typeId;
+        this.data = data;
+    }
+
+    public ParentEntity(Long id, Long typeId, String data) {
+        this.id = id;
+        this.typeId = typeId;
+        this.data = data;
+    }
+
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof ParentEntity)) return false;
+
+        ParentEntity that = (ParentEntity) o;
+
+        if (id != null ? !id.equals(that.id) : that.id != null) return false;
+        if (typeId != null ? !typeId.equals(that.id) : that.typeId != null) return false;
+        if (data != null ? !data.equals(that.data) : that.data != null) return false;
+
+        return true;
+    }
+
+    public int hashCode() {
+        int result;
+        result = (id != null ? id.hashCode() : 0);
+        result = 31 * result + (typeId != null ? typeId.hashCode() : 0);
+        result = 31 * result + (data != null ? data.hashCode() : 0);
+        return result;
+    }
+
+    public String toString() {
+        return "ParentEntity(id = " + id + ", typeId = " + typeId + ", data = " + data + ")";
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public Long getTypeId() {
+        return typeId;
+    }
+
+    public void setTypeId(Long typeId) {
+        this.typeId = typeId;
+    }
+
+    public String getData() {
+        return data;
+    }
+
+    public void setData(String data) {
+        this.data = data;
+    }
+}