/*
* Copyright 2002-2006 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.orm.jpa.persistenceunit;
import java.lang.instrument.ClassFileTransformer;
import java.security.ProtectionDomain;
import javax.persistence.spi.ClassTransformer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.util.Assert;
/**
* Simple adapter that implements the <code>java.lang.instrument.ClassFileTransformer</code>
* interface based on a JPA ClassTransformer which a JPA PersistenceProvider asks the
* PersistenceUnitInfo to install in the current runtime.
*
* @author Rod Johnson
* @since 2.0
* @see javax.persistence.spi.PersistenceUnitInfo#addTransformer(javax.persistence.spi.ClassTransformer)
*/
class ClassFileTransformerAdapter implements ClassFileTransformer {
private static final Log logger = LogFactory.getLog(ClassFileTransformerAdapter.class);
private final ClassTransformer classTransformer;
public ClassFileTransformerAdapter(ClassTransformer classTransformer) {
Assert.notNull(classTransformer, "ClassTransformer must not be null");
this.classTransformer = classTransformer;
}
public byte[] transform(
ClassLoader loader, String className, Class<?> classBeingRedefined,
ProtectionDomain protectionDomain, byte[] classfileBuffer) {
try {
byte[] transformed = this.classTransformer.transform(
loader, className, classBeingRedefined, protectionDomain, classfileBuffer);
if (transformed != null && logger.isDebugEnabled()) {
logger.debug("Transformer of class [" + this.classTransformer.getClass().getName() +
"] transformed class [" + className + "]; bytes in=" +
classfileBuffer.length + "; bytes out=" + transformed.length);
}
return transformed;
}
catch (ClassCircularityError ex) {
logger.error("Error weaving class [" + className + "] with " +
"transformer of class [" + this.classTransformer.getClass().getName() + "]", ex);
throw new IllegalStateException("Could not weave class [" + className + "]", ex);
}
catch (Throwable ex) {
if (logger.isWarnEnabled()) {
logger.warn("Error weaving class [" + className + "] with " +
"transformer of class [" + this.classTransformer.getClass().getName() + "]", ex);
}
// The exception will be ignored by the class loader, anyway...
throw new IllegalStateException("Could not weave class [" + className + "]", ex);
}
}
@Override
public String toString() {
return "Standard ClassFileTransformer wrapping JPA transformer: " + this.classTransformer;
}
}
|