JRockitPreProcessor.java

/**************************************************************************************
 * Copyright (c) Jonas Bon�r, Alexandre Vasseur. All rights reserved.                 *
 * http://aspectwerkz.codehaus.org                                                    *
 * ---------------------------------------------------------------------------------- *
 * The software in this package is published under the terms of the LGPL license      *
 * a copy of which has been included with this distribution in the license.txt file.  *
 **************************************************************************************/
package org.codehaus.aspectwerkz.extension.jrockit;

import org.codehaus.aspectwerkz.hook.ClassPreProcessor;
import org.codehaus.aspectwerkz.hook.impl.ClassPreProcessorHelper;
import com.bea.jvm.JVMFactory;
import com.jrockit.management.rmp.RmpSocketListener;

/**
 * JRockit (tested with 7SP4 and 8.1) preprocessor Adapter based on JMAPI <p/>JRockit has a low
 * level API for hooking ClassPreProcessor, allowing the use of online weaving at full speed.
 * Moreover, JRockit does not allow java.lang.ClassLoader overriding thru -Xbootclasspath/p option.
 * <p/>The main difference with standard AspectWerkz online mode is that the ClassPreProcessor
 * implementation and all third party jars CAN reside in the standard classpath. <p/>The command
 * line tool will look like:
 * <code>"%JAVA_COMMAND%" -Xmanagement:class=org.codehaus.aspectwerkz.extension.jrockit.JRockitPreProcessor
 * -cp "%ASPECTWERKZ_HOME%\target\aspectwerkz-extensions-%ASPECTWERKZ_VERSION%.jar;%ASPECTWERKZ_HOME%\lib\aspectwerkz-core-%ASPECTWERKZ_VERSION%.jar;%ASPECTWERKZ_HOME%\lib\aspectwerkz-%ASPECTWERKZ_VERSION%.jar;%ASPECTWERKZ_LIBS%"
 * -Daspectwerkz.transform.verbose=yes %*</code>
 * Note: there can be some NoClassDefFoundError due to classpath limitation - as described in
 * http://edocs.bea.com/wls/docs81/adminguide/winservice.html <p/>In order to use the BEA JRockit
 * management server (for further connection of management console or runtime analyzer), the regular
 * option -Xmanagement will not have any effect. Instead, use <code>-Dmanagement</code>.
 *
 * @author <a href="mailto:alex@gnilux.com">Alexandre Vasseur </a>
 * @author <a href="mailto:jboner@codehaus.org">Jonas Bon�r </a>
 */
public class JRockitPreProcessor implements com.bea.jvm.ClassPreProcessor {

    /**
     * Concrete AspectWerkz preprocessor.
     */
    private static ClassPreProcessor s_preProcessor;

    private static boolean START_RMP_SERVER = false;

    static {
        String clpp = System.getProperty(
                "aspectwerkz.classloader.preprocessor",
                "org.codehaus.aspectwerkz.transform.AspectWerkzPreProcessor"
        );
        START_RMP_SERVER = System.getProperties().containsKey("management");
        try {
            // note: CLPP loaded by current thread classloader which is bootstrap classloader
            // caution: forcing loading thru Thread.setContextClassLoader() or
            // ClassLoader.getSystemClassLoader()
            // does not work. We then do a filtering on the caller classloader - see preProcess(..)
            //preProcessor = (ClassPreProcessor) Class.forName(clpp).newInstance();
            s_preProcessor = ClassPreProcessorHelper.getClassPreProcessor();
            //(ClassPreProcessor)ClassLoader.getSystemClassLoader().loadClass(clpp).newInstance();
            //s_preProcessor.initialize(null);
        } catch (Exception e) {
            throw new ExceptionInInitializerError("could not initialize jrockit preprocessor due to: " + e.toString());
        }
    }

    /**
     * The JMAPI ClassPreProcessor must be self registrating
     */
    public JRockitPreProcessor() {
        if (START_RMP_SERVER) {
            // the management server will be spawned in a new thread
            RmpSocketListener management = new RmpSocketListener();
        }
        JVMFactory.getJVM().getClassLibrary().setClassPreProcessor(this);
    }

    /**
     * Weave a class
     *
     * @param caller   classloader
     * @param name     of the class to weave
     * @param bytecode original
     * @return bytecode weaved
     */
    public byte[] preProcess(ClassLoader caller, String name, byte[] bytecode) {
        if (caller == null || caller.getParent() == null) {
            return bytecode;
        } else {
            return s_preProcessor.preProcess(name, bytecode, caller);
        }
    }

    /**
     * Utility for testing
     */
    public static void main(String args[]) throws Throwable {
        // uncomment this lines to programmaticaly configure at runtime the CLPP
        JRockitPreProcessor pp = new JRockitPreProcessor();//self registration
        Class loadedCP = Class.forName("java.math.BigDecimal");
        while (true) {
            System.out.print(".");
            /*
             * ClassLoader nonDelegatingCL = new VerifierClassLoader( new URL[]{(new
             * File(args[0])).toURL()}, ClassLoader.getSystemClassLoader() ); Class loaded =
             * nonDelegatingCL.loadClass(
             * org.codehaus.aspectwerkz.extension.jrockit.JRockitPreProcessor.class.getName() );
             */
            Thread.sleep(500);
        }
    }
}