HHH-6696 - RevisionListener class configuration parameter

documentation/src/main/docbook/devguide/en-US/Envers.xml

@@ -407,6 +407,10 @@
                     You tell Envers your custom <interfacename>org.hibernate.envers.RevisionListener</interfacename>
                     implementation to use by specifying it on the
                     <interfacename>@org.hibernate.envers.RevisionEntity</interfacename> annotation, using the
+                    <methodname>value</methodname> attribute. If your <interfacename>RevisionListener</interfacename>
+                    class is inaccessible from <interfacename>@RevisionEntity</interfacename> (e.g. exists in a different
+                    module), set <property>org.hibernate.envers.revision_listener</property> property to it's fully
+                    qualified name. Class name defined by the configuration parameter overrides revision entity's
                     <methodname>value</methodname> attribute. 
                 </para>
             </listitem>

hibernate-envers/src/main/java/org/hibernate/envers/configuration/GlobalConfiguration.java

@@ -22,6 +22,9 @@
  * Boston, MA  02110-1301  USA
  */
 package org.hibernate.envers.configuration;
+import org.hibernate.MappingException;
+import org.hibernate.envers.RevisionListener;
+
 import static org.hibernate.envers.tools.Tools.getProperty;
 import java.util.Properties;
 
@@ -49,6 +52,9 @@ public class GlobalConfiguration {
     // Should Envers track (persist) entity names that have been changed during each revision.
     private boolean trackEntitiesChangedInRevisionEnabled;
 
+    // Revision listener class name.
+    private final Class<? extends RevisionListener> revisionListenerClass;
+
     /*
      Which operator to use in correlated subqueries (when we want a property to be equal to the result of
      a correlated subquery, for example: e.p <operator> (select max(e2.p) where e2.p2 = e.p2 ...).
@@ -87,6 +93,17 @@ public class GlobalConfiguration {
         		"org.hibernate.envers.track_entities_changed_in_revision",
         		"false");
         trackEntitiesChangedInRevisionEnabled = Boolean.parseBoolean(trackEntitiesChangedInRevisionEnabledStr);
+
+        String revisionListenerClassName = properties.getProperty("org.hibernate.envers.revision_listener", null);
+        if (revisionListenerClassName != null) {
+            try {
+                revisionListenerClass = (Class<? extends RevisionListener>) Thread.currentThread().getContextClassLoader().loadClass(revisionListenerClassName);
+            } catch (ClassNotFoundException e) {
+                throw new MappingException("Revision listener class not found: " + revisionListenerClassName + ".", e);
+            }
+        } else {
+            revisionListenerClass = null;
+        }
     }
 
     public boolean isGenerateRevisionsForCollections() {
@@ -120,4 +137,8 @@ public class GlobalConfiguration {
     public void setTrackEntitiesChangedInRevisionEnabled(boolean trackEntitiesChangedInRevisionEnabled) {
         this.trackEntitiesChangedInRevisionEnabled = trackEntitiesChangedInRevisionEnabled;
     }
+
+    public Class<? extends RevisionListener> getRevisionListenerClass() {
+        return revisionListenerClass;
+    }
 }

hibernate-envers/src/main/java/org/hibernate/envers/configuration/RevisionInfoConfiguration.java

@@ -286,8 +286,8 @@ public class RevisionInfoConfiguration {
                 }
 
                 revisionInfoEntityName = pc.getEntityName();
-
                 revisionInfoClass = pc.getMappedClass();
+                Class<? extends RevisionListener> revisionListenerClass = getRevisionListenerClass(revisionEntity.value());
                 revisionInfoTimestampType = pc.getProperty(revisionInfoTimestampData.getName()).getType();
                 if (globalCfg.isTrackEntitiesChangedInRevisionEnabled() ||
                         DefaultTrackingModifiedEntitiesRevisionEntity.class.isAssignableFrom(revisionInfoClass) ||
@@ -295,12 +295,12 @@ public class RevisionInfoConfiguration {
                     // If tracking modified entities parameter is enabled, custom revision info entity is a subtype
                     // of DefaultTrackingModifiedEntitiesRevisionEntity class, or @ModifiedEntityNames annotation is used.
                     revisionInfoGenerator = new DefaultTrackingModifiedEntitiesRevisionInfoGenerator(revisionInfoEntityName,
-                            revisionInfoClass, revisionEntity.value(), revisionInfoTimestampData, isTimestampAsDate(),
+                            revisionInfoClass, revisionListenerClass, revisionInfoTimestampData, isTimestampAsDate(),
                             modifiedEntityNamesData);
                     globalCfg.setTrackEntitiesChangedInRevisionEnabled(true);
                 } else {
                     revisionInfoGenerator = new DefaultRevisionInfoGenerator(revisionInfoEntityName, revisionInfoClass,
-                            revisionEntity.value(), revisionInfoTimestampData, isTimestampAsDate());
+                            revisionListenerClass, revisionInfoTimestampData, isTimestampAsDate());
                 }
             }
         }
@@ -308,16 +308,18 @@ public class RevisionInfoConfiguration {
         // In case of a custom revision info generator, the mapping will be null.
         Document revisionInfoXmlMapping = null;
 
+        Class<? extends RevisionListener> revisionListenerClass = getRevisionListenerClass(RevisionListener.class);
+
         if (revisionInfoGenerator == null) {
             if (globalCfg.isTrackEntitiesChangedInRevisionEnabled()) {
                 revisionInfoClass = DefaultTrackingModifiedEntitiesRevisionEntity.class;
                 revisionInfoEntityName = DefaultTrackingModifiedEntitiesRevisionEntity.class.getName();
                 revisionInfoGenerator = new DefaultTrackingModifiedEntitiesRevisionInfoGenerator(revisionInfoEntityName, revisionInfoClass,
-                        RevisionListener.class, revisionInfoTimestampData, isTimestampAsDate(), modifiedEntityNamesData);
+                        revisionListenerClass, revisionInfoTimestampData, isTimestampAsDate(), modifiedEntityNamesData);
             } else {
                 revisionInfoClass = DefaultRevisionEntity.class;
                 revisionInfoGenerator = new DefaultRevisionInfoGenerator(revisionInfoEntityName, revisionInfoClass,
-                        RevisionListener.class, revisionInfoTimestampData, isTimestampAsDate());
+                        revisionListenerClass, revisionInfoTimestampData, isTimestampAsDate());
             }
             revisionInfoXmlMapping = generateDefaultRevisionInfoXmlMapping();
         }
@@ -337,6 +339,18 @@ public class RevisionInfoConfiguration {
     	String typename = revisionInfoTimestampType.getName();
     	return "date".equals(typename) || "time".equals(typename) || "timestamp".equals(typename);
     }
+
+    /**
+     * @param defaultListener Revision listener that shall be applied if {@code org.hibernate.envers.revision_listener}
+     *                        parameter has not been set.
+     * @return Revision listener.  
+     */
+    private Class<? extends RevisionListener> getRevisionListenerClass(Class<? extends RevisionListener> defaultListener) {
+        if (globalCfg.getRevisionListenerClass() != null) {
+            return globalCfg.getRevisionListenerClass();
+        }
+        return defaultListener;
+    }
 }
 
 class RevisionInfoConfigurationResult {

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/reventity/CountingRevisionListener.java

@@ -0,0 +1,15 @@
+package org.hibernate.envers.test.integration.reventity;
+
+import org.hibernate.envers.RevisionListener;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+public class CountingRevisionListener implements RevisionListener {
+    public static int revisionCount = 0;
+
+    @Override
+    public void newRevision(Object revisionEntity) {
+        ++revisionCount;
+    }
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/reventity/GloballyConfiguredRevListenerTest.java

@@ -0,0 +1,36 @@
+package org.hibernate.envers.test.integration.reventity;
+
+import org.hibernate.ejb.Ejb3Configuration;
+import org.hibernate.envers.test.AbstractEntityTest;
+import org.hibernate.envers.test.Priority;
+import org.hibernate.envers.test.entities.StrTestEntity;
+import org.junit.Assert;
+import org.junit.Test;
+
+import javax.persistence.EntityManager;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+public class GloballyConfiguredRevListenerTest extends AbstractEntityTest {
+    public void configure(Ejb3Configuration cfg) {
+        cfg.addAnnotatedClass(StrTestEntity.class);
+        cfg.setProperty("org.hibernate.envers.revision_listener", "org.hibernate.envers.test.integration.reventity.CountingRevisionListener");
+    }
+
+    @Test
+    @Priority(10)
+    public void initData() {
+        EntityManager em = getEntityManager();
+
+        CountingRevisionListener.revisionCount = 0;
+
+        // Revision 1
+        em.getTransaction().begin();
+        StrTestEntity te = new StrTestEntity("data");
+        em.persist(te);
+        em.getTransaction().commit();
+
+        Assert.assertEquals(1, CountingRevisionListener.revisionCount);
+    }
+}

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/reventity/OverrideRevListenerTest.java

@@ -0,0 +1,14 @@
+package org.hibernate.envers.test.integration.reventity;
+
+import org.hibernate.ejb.Ejb3Configuration;
+
+/**
+ * @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
+ */
+public class OverrideRevListenerTest extends GloballyConfiguredRevListenerTest {
+    @Override
+    public void configure(Ejb3Configuration cfg) {
+        super.configure(cfg);
+        cfg.addAnnotatedClass(ListenerRevEntity.class);
+    }
+}