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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
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package org.apache.cayenne.jpa.instrument;
import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.IllegalClassFormatException;
import java.lang.instrument.Instrumentation;
import java.security.ProtectionDomain;
import javax.persistence.spi.ClassTransformer;
import org.apache.cayenne.instrument.InstrumentUtil;
import org.apache.cayenne.jpa.JpaUnit;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* A unit that loads all transformers into a shared Instrumentation instance.
*
*/
public class InstrumentingUnit extends JpaUnit {
protected Log logger;
@Override
public void addTransformer(final ClassTransformer transformer) {
// wrap in a ClassFileTransformer
ClassFileTransformer transformerWrapper = new ClassFileTransformer() {
public byte[] transform(
ClassLoader loader,
String className,
Class<?> classBeingRedefined,
ProtectionDomain protectionDomain,
byte[] classfileBuffer) throws IllegalClassFormatException {
return transformer.transform(
loader,
className,
classBeingRedefined,
protectionDomain,
classfileBuffer);
}
};
getLogger().info("*** Adding transformer: " + transformer);
Instrumentation i = InstrumentUtil.getInstrumentation();
if (i == null) {
throw new IllegalStateException("Attempt to add a transformer failed - "
+ "instrumentation is not initialized.");
}
i.addTransformer(transformerWrapper);
}
protected Log getLogger() {
if (logger == null) {
logger = LogFactory.getLog(getClass());
}
return logger;
}
}