HHH-7667 - Investigate expanding bytecode enhancement support

hibernate-core/src/main/java/org/hibernate/bytecode/enhance/spi/EnhancementContext.java

@@ -23,12 +23,40 @@
  */
 package org.hibernate.bytecode.enhance.spi;
 
-import java.security.ProtectionDomain;
+import javassist.CtField;
 
 /**
  * @author Steve Ebersole
  */
 public interface EnhancementContext {
+	/**
+	 * Does the given class name represent a entity class?
+	 *
+	 * @param className The name of the class to check.
+	 *
+	 * @return {@code true} if the class is an entity; {@code false} otherwise.
+	 */
 	public boolean isEntityClass(String className);
+
+	/**
+	 * Does the given class name represent an embeddable/component class?
+	 *
+	 * @param className The name of the class to check.
+	 *
+	 * @return {@code true} if the class is an embeddable/component; {@code false} otherwise.
+	 */
 	public boolean isCompositeClass(String className);
+
+	/**
+	 * Does the field represent persistent state?  Persistent fields will be "enhanced".
+	 * <p/>
+	 * todo : not sure its a great idea to expose Javassist classes this way.
+	 // 		may be better to perform basic checks in the caller (non-static, etc) and call out with just the
+	 // 		Class name and field name...
+
+	 * @param ctField The field reference.
+	 *
+	 * @return {@code true} if the field is ; {@code false} otherwise.
+	 */
+ 	public boolean isPersistentField(CtField ctField);
 }

hibernate-core/src/main/java/org/hibernate/bytecode/enhance/spi/Enhancer.java

@@ -28,11 +28,13 @@ import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
+import java.util.IdentityHashMap;
 
 import javassist.CannotCompileException;
 import javassist.ClassPool;
 import javassist.CtClass;
 import javassist.CtField;
+import javassist.CtMethod;
 import javassist.CtNewMethod;
 import javassist.Modifier;
 import javassist.bytecode.AnnotationsAttribute;
@@ -44,7 +46,7 @@ import org.jboss.logging.Logger;
 
 import org.hibernate.HibernateException;
 import org.hibernate.bytecode.enhance.EnhancementException;
-import org.hibernate.bytecode.internal.javassist.FieldHandled;
+import org.hibernate.engine.spi.Managed;
 import org.hibernate.engine.spi.ManagedComposite;
 import org.hibernate.engine.spi.ManagedEntity;
 import org.hibernate.engine.spi.EntityEntry;
@@ -57,6 +59,9 @@ import org.hibernate.internal.CoreMessageLogger;
 public class Enhancer  {
 	private static final CoreMessageLogger log = Logger.getMessageLogger( CoreMessageLogger.class, Enhancer.class.getName() );
 
+	private static final String PERSISTENT_FIELD_READER_PREFIX = "$hibernate_read_";
+	private static final String PERSISTENT_FIELD_WRITER_PREFIX = "$hibernate_write_";
+
 	public static final String ENTITY_INSTANCE_GETTER_NAME = "hibernate_getEntityInstance";
 
 	public static final String ENTITY_ENTRY_FIELD_NAME = "$hibernate_entityEntryHolder";
@@ -168,7 +173,7 @@ public class Enhancer  {
 
 		final String[] interfaceNames = managedCtClass.getClassFile2().getInterfaces();
 		for ( String interfaceName : interfaceNames ) {
-			if ( FieldHandled.class.getName().equals( interfaceName ) ) {
+			if ( Managed.class.getName().equals( interfaceName ) ) {
 				log.debug( "skipping enhancement : already enhanced" );
 				return;
 			}
@@ -191,13 +196,18 @@ public class Enhancer  {
 		// add the ManagedEntity interface
 		managedCtClass.addInterface( managedEntityCtClass );
 
-		addEntityInstanceHandling( managedCtClass, constPool );
+//		enhancePersistentAttributes( managedCtClass );
-		addEntityEntryHandling( managedCtClass, constPool );
+
-		addLinkedPreviousHandling( managedCtClass, constPool );
+		addEntityInstanceHandling( managedCtClass );
-		addLinkedNextHandling( managedCtClass, constPool );
+		addEntityEntryHandling( managedCtClass );
+		addLinkedPreviousHandling( managedCtClass );
+		addLinkedNextHandling( managedCtClass );
 	}
 
-	private void addEntityInstanceHandling(CtClass managedCtClass, ConstPool constPool) {
+	private void enhanceAsComposite(CtClass classFile) {
+	}
+
+	private void addEntityInstanceHandling(CtClass managedCtClass) {
 		// add the ManagedEntity#hibernate_getEntityInstance method
 		try {
 			managedCtClass.addMethod(
@@ -224,7 +234,9 @@ public class Enhancer  {
 		// essentially add `return this;`
 	}
 
-	private void addEntityEntryHandling(CtClass managedCtClass, ConstPool constPool) {
+	private void addEntityEntryHandling(CtClass managedCtClass) {
+		final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
+
 		// add field to hold EntityEntry
 		final CtField entityEntryField;
 		try {
@@ -243,6 +255,7 @@ public class Enhancer  {
 
 		// make that new field transient and @Transient
 		entityEntryField.setModifiers( entityEntryField.getModifiers() | Modifier.TRANSIENT );
+		entityEntryField.setModifiers( Modifier.setPrivate( entityEntryField.getModifiers() ) );
 		AnnotationsAttribute annotationsAttribute = getVisibleAnnotations( entityEntryField.getFieldInfo() );
 		annotationsAttribute.addAnnotation( new Annotation( Transient.class.getName(), constPool ) );
 
@@ -279,11 +292,13 @@ public class Enhancer  {
 		}
 	}
 
-	private void addLinkedPreviousHandling(CtClass managedCtClass, ConstPool constPool) {
+	private void addLinkedPreviousHandling(CtClass managedCtClass) {
+		final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
+
 		// add field to hold "previous" ManagedEntity
 		final CtField previousField;
 		try {
-			previousField = new CtField( managedCtClass, PREVIOUS_FIELD_NAME, managedCtClass );
+			previousField = new CtField( managedEntityCtClass, PREVIOUS_FIELD_NAME, managedCtClass );
 			managedCtClass.addField( previousField );
 		}
 		catch (CannotCompileException e) {
@@ -298,6 +313,7 @@ public class Enhancer  {
 
 		// make that new field transient and @Transient
 		previousField.setModifiers( previousField.getModifiers() | Modifier.TRANSIENT );
+		previousField.setModifiers( Modifier.setPrivate( previousField.getModifiers() ) );
 		AnnotationsAttribute annotationsAttribute = getVisibleAnnotations( previousField.getFieldInfo() );
 		annotationsAttribute.addAnnotation( new Annotation( Transient.class.getName(), constPool ) );
 
@@ -330,11 +346,13 @@ public class Enhancer  {
 		}
 	}
 
-	private void addLinkedNextHandling(CtClass managedCtClass, ConstPool constPool) {
+	private void addLinkedNextHandling(CtClass managedCtClass) {
+		final ConstPool constPool = managedCtClass.getClassFile().getConstPool();
+
 		// add field to hold "next" ManagedEntity
 		final CtField nextField;
 		try {
-			nextField = new CtField( managedCtClass, NEXT_FIELD_NAME, managedCtClass );
+			nextField = new CtField( managedEntityCtClass, NEXT_FIELD_NAME, managedCtClass );
 			managedCtClass.addField( nextField );
 		}
 		catch (CannotCompileException e) {
@@ -347,8 +365,9 @@ public class Enhancer  {
 			);
 		}
 
-		// make that new field transient and @Transient
+		// make that new field (1) private, (2) transient and (3) @Transient
 		nextField.setModifiers( nextField.getModifiers() | Modifier.TRANSIENT );
+		nextField.setModifiers( Modifier.setPrivate( nextField.getModifiers() ) );
 		AnnotationsAttribute annotationsAttribute = getVisibleAnnotations( nextField.getFieldInfo() );
 		annotationsAttribute.addAnnotation( new Annotation( Transient.class.getName(), constPool ) );
 
@@ -390,8 +409,84 @@ public class Enhancer  {
 		return annotationsAttribute;
 	}
 
-	private void enhanceAsComposite(CtClass classFile) {
+	private void enhancePersistentAttributes(CtClass managedCtClass) {
+		final IdentityHashMap<CtField,FieldVirtualReadWritePair> fieldToMethodsXref = new IdentityHashMap<CtField, FieldVirtualReadWritePair>();
+
+		for ( CtField ctField : managedCtClass.getFields() ) {
+			if ( ! enhancementContext.isPersistentField( ctField ) ) {
+				continue;
+			}
+
+			final FieldVirtualReadWritePair methodPair = addReadAndWriteMethod( managedCtClass, ctField );
+			fieldToMethodsXref.put( ctField, methodPair );
+		}
+
+		transformFieldAccessesIntoReadsAndWrites( managedCtClass, fieldToMethodsXref );
 	}
 
+	private FieldVirtualReadWritePair addReadAndWriteMethod(CtClass managedCtClass, CtField persistentField) {
+		// add the "reader"
+		final CtMethod reader = generateFieldReader( managedCtClass, persistentField );
+
+		// add the "writer"
+		final CtMethod writer = generateFieldWriter( managedCtClass, persistentField );
+
+		return new FieldVirtualReadWritePair( reader, writer );
+	}
+
+	private CtMethod generateFieldReader(CtClass managedCtClass, CtField persistentField) {
+		// todo : temporary; still need to add hooks into lazy-loading
+		try {
+			final String name = PERSISTENT_FIELD_READER_PREFIX + persistentField.getName();
+			CtMethod reader = CtNewMethod.getter( name, persistentField );
+			managedCtClass.addMethod( reader );
+			return reader;
+		}
+		catch (CannotCompileException e) {
+			throw new EnhancementException(
+					String.format(
+							"Could not enhance entity class [%s] to add virtual reader method for field [%s]",
+							managedCtClass.getName(),
+							persistentField.getName()
+					),
+					e
+			);
+		}
+	}
+
+	private CtMethod generateFieldWriter(CtClass managedCtClass, CtField persistentField) {
+		// todo : temporary; still need to add hooks into lazy-loading and dirtying
+		try {
+			final String name = PERSISTENT_FIELD_WRITER_PREFIX + persistentField.getName();
+			CtMethod writer = CtNewMethod.setter( name, persistentField );
+			managedCtClass.addMethod( writer );
+			return writer;
+		}
+		catch (CannotCompileException e) {
+			throw new EnhancementException(
+					String.format(
+							"Could not enhance entity class [%s] to add virtual writer method for field [%s]",
+							managedCtClass.getName(),
+							persistentField.getName()
+					),
+					e
+			);
+		}
+	}
+
+	private void transformFieldAccessesIntoReadsAndWrites(
+			CtClass managedCtClass,
+			IdentityHashMap<CtField, FieldVirtualReadWritePair> fieldToMethodsXref) {
+	}
+
+	private static class FieldVirtualReadWritePair {
+		private final CtMethod readMethod;
+		private final CtMethod writeMethod;
+
+		private FieldVirtualReadWritePair(CtMethod readMethod, CtMethod writeMethod) {
+			this.readMethod = readMethod;
+			this.writeMethod = writeMethod;
+		}
+	}
 
 }

hibernate-core/src/main/java/org/hibernate/tool/enhance/EnhancementTask.java

@@ -24,6 +24,7 @@
 package org.hibernate.tool.enhance;
 
 import javax.persistence.Entity;
+import javax.persistence.Transient;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
@@ -33,7 +34,10 @@ import java.util.List;
 
 import javassist.ClassPool;
 import javassist.CtClass;
+import javassist.CtField;
 import javassist.NotFoundException;
+import javassist.bytecode.AnnotationsAttribute;
+import javassist.bytecode.annotation.Annotation;
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.DirectoryScanner;
 import org.apache.tools.ant.Project;
@@ -74,6 +78,12 @@ public class EnhancementTask extends Task {
 			public boolean isCompositeClass(String className) {
 				return false;
 			}
+
+			@Override
+			public boolean isPersistentField(CtField ctField) {
+				// current check is to look for @Transient
+				return ! ctField.hasAnnotation( Transient.class );
+			}
 		};
 
 		// we use the CtClass stuff here just as a simple vehicle for obtaining low level information about

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/EnhancerTest.java

@@ -36,6 +36,7 @@ import java.util.Arrays;
 import javassist.CannotCompileException;
 import javassist.ClassPool;
 import javassist.CtClass;
+import javassist.CtField;
 import javassist.LoaderClassPath;
 import javassist.NotFoundException;
 
@@ -44,68 +45,92 @@ import org.hibernate.LockMode;
 import org.hibernate.bytecode.enhance.spi.EnhancementContext;
 import org.hibernate.bytecode.enhance.spi.Enhancer;
 import org.hibernate.engine.spi.EntityEntry;
+import org.hibernate.engine.spi.ManagedEntity;
 import org.hibernate.engine.spi.Status;
 
 import org.junit.Test;
 
 import org.hibernate.testing.junit4.BaseUnitTestCase;
+import org.hibernate.testing.junit4.ExtraAssertions;
 
+import static org.hibernate.testing.junit4.ExtraAssertions.assertTyping;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertSame;
-import static org.junit.Assert.fail;
 
 /**
  * @author Steve Ebersole
  */
 public class EnhancerTest extends BaseUnitTestCase {
-	@Test
+	private static EnhancementContext enhancementContext = new EnhancementContext() {
-	public void testEnhancement()
+		@Override
-			throws IOException, CannotCompileException, NotFoundException,
+		public boolean isEntityClass(String className) {
-			NoSuchMethodException, IllegalAccessException, InstantiationException, InvocationTargetException {
+			return true;
-		EnhancementContext enhancementContext = new EnhancementContext() {
+		}
-			@Override
-			public boolean isEntityClass(String className) {
-				return true;
-			}
 
-			@Override
+		@Override
-			public boolean isCompositeClass(String className) {
+		public boolean isCompositeClass(String className) {
-				return false;
+			return false;
-			}
+		}
-		};
+
+		@Override
+		public boolean isPersistentField(CtField ctField) {
+			return true;
+		}
+	};
+
+	@Test
+	public void testEnhancement() throws Exception {
+		testFor( SimpleEntity.class );
+		testFor( SubEntity.class );
+	}
+
+	private void testFor(Class entityClassToEnhance) throws Exception {
 		Enhancer enhancer = new Enhancer( enhancementContext );
-		CtClass anEntityCtClass = generateCtClassForAnEntity();
+		CtClass entityCtClass = generateCtClassForAnEntity( entityClassToEnhance );
-		byte[] original = anEntityCtClass.toBytecode();
+		byte[] original = entityCtClass.toBytecode();
-		byte[] enhanced = enhancer.enhance( anEntityCtClass.getName(), original );
+		byte[] enhanced = enhancer.enhance( entityCtClass.getName(), original );
 		assertFalse( "entity was not enhanced", Arrays.equals( original, enhanced ) );
 
 		ClassLoader cl = new ClassLoader() { };
 		ClassPool cp2 = new ClassPool( false );
 		cp2.appendClassPath( new LoaderClassPath( cl ) );
 		CtClass enhancedCtClass = cp2.makeClass( new ByteArrayInputStream( enhanced ) );
-		Class simpleEntityClass = enhancedCtClass.toClass( cl, this.getClass().getProtectionDomain() );
+		Class entityClass = enhancedCtClass.toClass( cl, this.getClass().getProtectionDomain() );
-		Object simpleEntityInstance = simpleEntityClass.newInstance();
+		Object entityInstance = entityClass.newInstance();
+
+		assertTyping( ManagedEntity.class, entityInstance );
 
 		// call the new methods
-		Method setter = simpleEntityClass.getMethod( Enhancer.ENTITY_ENTRY_SETTER_NAME, EntityEntry.class );
+		//
-		Method getter = simpleEntityClass.getMethod( Enhancer.ENTITY_ENTRY_GETTER_NAME );
+		Method setter = entityClass.getMethod( Enhancer.ENTITY_ENTRY_SETTER_NAME, EntityEntry.class );
-		assertNull( getter.invoke( simpleEntityInstance ) );
+		Method getter = entityClass.getMethod( Enhancer.ENTITY_ENTRY_GETTER_NAME );
-		setter.invoke( simpleEntityInstance, makeEntityEntry() );
+		assertNull( getter.invoke( entityInstance ) );
-		assertNotNull( getter.invoke( simpleEntityInstance ) );
+		setter.invoke( entityInstance, makeEntityEntry() );
-		setter.invoke( simpleEntityInstance, new Object[] { null } );
+		assertNotNull( getter.invoke( entityInstance ) );
-		assertNull( getter.invoke( simpleEntityInstance ) );
+		setter.invoke( entityInstance, new Object[] {null} );
+		assertNull( getter.invoke( entityInstance ) );
 
-		Method entityInstanceGetter = simpleEntityClass.getMethod( Enhancer.ENTITY_INSTANCE_GETTER_NAME );
+		Method entityInstanceGetter = entityClass.getMethod( Enhancer.ENTITY_INSTANCE_GETTER_NAME );
-		assertSame( simpleEntityInstance, entityInstanceGetter.invoke( simpleEntityInstance ) );
+		assertSame( entityInstance, entityInstanceGetter.invoke( entityInstance ) );
+
+		Method previousGetter = entityClass.getMethod( Enhancer.PREVIOUS_GETTER_NAME );
+		Method previousSetter = entityClass.getMethod( Enhancer.PREVIOUS_SETTER_NAME, ManagedEntity.class );
+		previousSetter.invoke( entityInstance, entityInstance );
+		assertSame( entityInstance, previousGetter.invoke( entityInstance ) );
+
+		Method nextGetter = entityClass.getMethod( Enhancer.PREVIOUS_GETTER_NAME );
+		Method nextSetter = entityClass.getMethod( Enhancer.PREVIOUS_SETTER_NAME, ManagedEntity.class );
+		nextSetter.invoke( entityInstance, entityInstance );
+		assertSame( entityInstance, nextGetter.invoke( entityInstance ) );
 	}
 
-	private CtClass generateCtClassForAnEntity() throws IOException, NotFoundException {
+	private CtClass generateCtClassForAnEntity(Class entityClassToEnhance) throws Exception {
 		ClassPool cp = new ClassPool( false );
 		return cp.makeClass(
 				getClass().getClassLoader().getResourceAsStream(
-						SimpleEntity.class.getName().replace( '.', '/' ) + ".class"
+						entityClassToEnhance.getName().replace( '.', '/' ) + ".class"
 				)
 		);
 	}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/SubEntity.java

@@ -0,0 +1,33 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2012, 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.bytecode.enhancement;
+
+import javax.persistence.Entity;
+
+/**
+ * @author Steve Ebersole
+ */
+@Entity
+public class SubEntity extends SuperEntity {
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/SuperEntity.java

@@ -0,0 +1,33 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2012, 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.bytecode.enhancement;
+
+import javax.persistence.Entity;
+
+/**
+ * @author Steve Ebersole
+ */
+@Entity
+public class SuperEntity {
+}