/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009, Red Hat Middleware LLC 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 Middleware LLC.
*
* 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.bytecode.buildtime;
import java.util.Set;
import java.io.ByteArrayInputStream;
import org.hibernate.bytecode.util.ClassDescriptor;
import org.hibernate.bytecode.util.BasicClassFilter;
import org.hibernate.bytecode.ClassTransformer;
import org.hibernate.bytecode.cglib.BytecodeProviderImpl;
import org.objectweb.asm.ClassReader;
import net.sf.cglib.core.ClassNameReader;
import net.sf.cglib.transform.impl.InterceptFieldEnabled;
/**
* Strategy for performing build-time instrumentation of persistent classes in order to enable
* field-level interception using CGLIB.
*
* @author Steve Ebersole
* @author Gavin King
*/
public class CGLIBInstrumenter extends AbstractInstrumenter {
private static final BasicClassFilter CLASS_FILTER = new BasicClassFilter();
private final BytecodeProviderImpl provider = new BytecodeProviderImpl();
public CGLIBInstrumenter(Logger logger, Options options) {
super( logger, options );
}
protected ClassDescriptor getClassDescriptor(byte[] byecode) throws Exception {
return new CustomClassDescriptor( byecode );
}
protected ClassTransformer getClassTransformer(ClassDescriptor descriptor, Set classNames) {
if ( descriptor.isInstrumented() ) {
logger.debug( "class [" + descriptor.getName() + "] already instrumented" );
return null;
}
else {
return provider.getTransformer( CLASS_FILTER, new CustomFieldFilter( descriptor, classNames ) );
}
}
private static class CustomClassDescriptor implements ClassDescriptor {
private final byte[] bytecode;
private final String name;
private final boolean isInstrumented;
public CustomClassDescriptor(byte[] bytecode) throws Exception {
this.bytecode = bytecode;
ClassReader reader = new ClassReader( new ByteArrayInputStream( bytecode ) );
String[] names = ClassNameReader.getClassInfo( reader );
this.name = names[0];
boolean instrumented = false;
for ( int i = 1; i < names.length; i++ ) {
if ( InterceptFieldEnabled.class.getName().equals( names[i] ) ) {
instrumented = true;
break;
}
}
this.isInstrumented = instrumented;
}
public String getName() {
return name;
}
public boolean isInstrumented() {
return isInstrumented;
}
public byte[] getBytes() {
return bytecode;
}
}
}