Copyright (c) 2005 Contributors.
All rights reserved.
This program and the accompanying materials are made available
under the terms of the Eclipse Public License v1.0
which accompanies this distribution and is available at
http://eclipse.org/legal/epl-v10.html
Contributors:
  Alexandre Vasseur         initial implementation
/*******************************************************************************
 * Copyright (c) 2005 Contributors.
 * All rights reserved.
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution and is available at
 * http://eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Alexandre Vasseur         initial implementation
 *******************************************************************************/
package org.aspectj.weaver.loadtime;

import java.lang.instrument.Instrumentation;
import java.lang.instrument.ClassFileTransformer;

Java 1.5 preMain agent to hook in the class pre processor
Can be used with -javaagent:aspectjweaver.jar
Author:
Alexandre Vasseur, Alexander Kriegisch/**
 * Java 1.5 preMain agent to hook in the class pre processor
 * Can be used with -javaagent:aspectjweaver.jar
 *
 * @author Alexandre Vasseur
 * @author Alexander Kriegisch
 */
public class Agent { 

    
The instrumentation instance
/**
     * The instrumentation instance
     */
    private static Instrumentation s_instrumentation;

    
The ClassFileTransformer wrapping the weaver
/**
     * The ClassFileTransformer wrapping the weaver
     */
    private static ClassFileTransformer s_transformer = new ClassPreProcessorAgentAdapter();

    
JSR-163 preMain Agent entry method
Params:
options – 
instrumentation – /**
     * JSR-163 preMain Agent entry method
     *
     * @param options
     * @param instrumentation 
     */
    public static void premain(String options, Instrumentation instrumentation) {
    	/* Handle duplicate agents */
    	if (s_instrumentation != null) {
    		return;
    	}
        s_instrumentation = instrumentation;
        s_instrumentation.addTransformer(s_transformer);
    }

    public static void agentmain(String options, Instrumentation instrumentation) {
        premain(options, instrumentation);
    }

    
Returns the Instrumentation system level instance
/**
     * Returns the Instrumentation system level instance
     */
    public static Instrumentation getInstrumentation() {
        if (s_instrumentation == null) {
            throw new UnsupportedOperationException(
                "AspectJ weaving agent was neither started via '-javaagent' (preMain) " +
                "nor attached via 'VirtualMachine.loadAgent' (agentMain)");
        }
        return s_instrumentation;
    }

}