/**************************************************************************************
 * Copyright (c) Jonas Bonér, 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 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\extensions.jar;%ASPECTWERKZ_HOME%\lib\javassist-2.6.jar;%ASPECTWERKZ_HOME%\lib\bcel-patch.jar;%ASPECTWERKZ_HOME%\lib\bcel.jar;%ASPECTWERKZ_HOME%\lib\aspectwerkz-core-%ASPECTWERKZ_VERSION%.jar;%ASPECTWERKZ_HOME%\lib\aspectwerkz-%ASPECTWERKZ_VERSION%.jar;%ASPECTWERKZ_LIBS%"
 * -Daspectwerkz.home="%ASPECTWERKZ_HOME%" -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 Bonér</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 = (ClassPreProcessor)ClassLoader.getSystemClassLoader().loadClass(clpp).newInstance();
            s_preProcessor.initialize(null);
        }
        catch (Exception e) {
            throw new ExceptionInInitializerError(e);
        }
    }

    /**
     * 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) {
//        System.out.println(name + " [" + caller + "]");
        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");

        //System.out.println(org.codehaus.aspectwerkz.Pointcut.class.getClassLoader());

        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);
        }
    }
}
