org/objectweb/proactive/core/classloader/ProActiveClassLoaderHelper.java

/* 
 * ################################################################
 * 
 * ProActive: The Java(TM) library for Parallel, Distributed, 
 *            Concurrent computing with Security and Mobility
 * 
 * Copyright (C) 1997-2007 INRIA/University of Nice-Sophia Antipolis
 * Contact: proactive@objectweb.org
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 *  
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA
 *  
 *  Initial developer(s):               The ProActive Team
 *                        http://www.inria.fr/oasis/ProActive/contacts.html
 *  Contributor(s): 
 * 
 * ################################################################
 */ 
package org.objectweb.proactive.core.classloader;

import org.apache.log4j.Logger;
import org.objectweb.proactive.core.mop.JavassistByteCodeStubBuilder;
import org.objectweb.proactive.core.mop.MOPClassLoader;
import org.objectweb.proactive.core.mop.Utils;
import org.objectweb.proactive.core.runtime.ProActiveRuntimeImpl;
import org.objectweb.proactive.core.util.ClassDataCache;
import org.objectweb.proactive.core.util.log.Loggers;
import org.objectweb.proactive.core.util.log.ProActiveLogger;


public class ProActiveClassLoaderHelper {
    private static Logger logger = ProActiveLogger.getLogger(Loggers.CLASSLOADING);
    private ClassDataCache classCache;

    public ProActiveClassLoaderHelper() {
        classCache = ClassDataCache.instance();
    }

    public synchronized byte[] getClassData(String className) throws ClassNotFoundException {
        byte[] class_data = null;

        // 1. look in class cache
        debug("looking for " + className + "  in class data cache");
        class_data = classCache.getClassData(className);
        if (class_data != null) {
            debug("found " + className + " in class data cache");
            return class_data;
        }

        // 2. look in runtime parents
        try {
            debug("looking for " + className + " in parent runtimes");

            class_data = ProActiveRuntimeImpl.getProActiveRuntime()
                                             .getClassDataFromParentRuntime(className);
            if (class_data != null) {
                debug("found " + className + " in ancestor runtime");
                return class_data;
            }
        } catch (Exception e) {
            e.printStackTrace();
            // continue
        }

        // 3. standard proactive stub?
        if (Utils.isStubClassName(className)) {
            // do not use directly MOP methods
            logger.info("Generating class : " + className);
            //    e.printStackTrace();
            String classname = Utils.convertStubClassNameToClassName(className);

            //ASM is now the default bytecode manipulator
//            if (MOPClassLoader.BYTE_CODE_MANIPULATOR.equals("ASM")) {
//                ASMBytecodeStubBuilder bsb = new ASMBytecodeStubBuilder(classname);
//                class_data = bsb.create();
//            } else 
                if (MOPClassLoader.BYTE_CODE_MANIPULATOR.equals("javassist")) {
                class_data = JavassistByteCodeStubBuilder.create(classname, null);
            } else {
                // that shouldn't happen, unless someone manually sets the BYTE_CODE_MANIPULATOR static variable
                System.err.println(
                    "byteCodeManipulator argument is optionnal. If specified, it can only be set to javassist (ASM is no longer supported).");
                System.err.println(
                    "Any other setting will result in the use of javassist, the default bytecode manipulator framework");
            }
            if (class_data != null) {
                classCache.addClassData(className, class_data);
                return class_data;
            }
        }

        if (class_data != null) {
            return class_data;
        }

        // component-generated?
        class_data = org.objectweb.proactive.core.component.gen.Utils.getClassData(className);

        if (class_data != null) {
            classCache.addClassData(className, class_data);
            return class_data;
        }

        throw new ClassNotFoundException(className);
    }

    private void debug(String message) {
        if (logger.isDebugEnabled()) {
            logger.debug(ProActiveRuntimeImpl.getProActiveRuntime().getURL() +
                " --> " + message);
        }
    }
}

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