org.springframework.instrument.classloading.oc4j.OC4JClassPreprocessorAdapter Maven / Gradle / Ivy
/*
* 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.instrument.classloading.oc4j;
import oracle.classloader.util.ClassPreprocessor;
import org.springframework.util.Assert;
import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.IllegalClassFormatException;
import java.security.ProtectionDomain;
/**
* {@link ClassPreprocessor} adapter for OC4J, delegating to a standard
* JDK {@link ClassFileTransformer} underneath.
*
* Many thanks to Mike Keith
* for his assistance.
*
* @author Costin Leau
* @since 2.0
*/
class OC4JClassPreprocessorAdapter implements ClassPreprocessor {
private final ClassFileTransformer transformer;
/**
* Creates a new instance of the {@link OC4JClassPreprocessorAdapter} class.
* @param transformer the {@link ClassFileTransformer} to be adapted (must not be null)
* @throws IllegalArgumentException if the supplied transformer is null
*/
public OC4JClassPreprocessorAdapter(ClassFileTransformer transformer) {
Assert.notNull(transformer, "Transformer must not be null");
this.transformer = transformer;
}
public ClassPreprocessor initialize(ClassLoader loader) {
return this;
}
public byte[] processClass(String className, byte origClassBytes[], int offset, int length, ProtectionDomain pd,
ClassLoader loader) {
try {
byte[] tempArray = new byte[length];
System.arraycopy(origClassBytes, offset, tempArray, 0, length);
// NB: OC4J passes className as "." without class while the
// transformer expects a VM, "/" format
byte[] result = this.transformer.transform(loader, className.replace('.', '/'), null, pd, tempArray);
return (result != null ? result : origClassBytes);
}
catch (IllegalClassFormatException ex) {
throw new IllegalStateException("Cannot transform because of illegal class format", ex);
}
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder(getClass().getName());
builder.append(" for transformer: ");
builder.append(this.transformer);
return builder.toString();
}
}