/*
 * Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

/*
 * @(#)file      MBeanServerForwarderInvocationHandler.java
 * @(#)author    Sun Microsystems, Inc.
 * @(#)version   1.4
 * @(#)date      07/08/30
 */

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import javax.management.MBeanServer;
import javax.management.remote.MBeanServerForwarder;

public class MBeanServerForwarderInvocationHandler
    implements InvocationHandler {

    public static MBeanServerForwarder newProxyInstance() {

	final InvocationHandler handler =
	    new MBeanServerForwarderInvocationHandler();

	final Class[] interfaces =
	    new Class[] {MBeanServerForwarder.class};

	Object proxy = Proxy.newProxyInstance(
		             MBeanServerForwarder.class.getClassLoader(),
			     interfaces,
			     handler);

	return MBeanServerForwarder.class.cast(proxy);
    }

    public Object invoke(Object proxy, Method method, Object[] args)
	throws Throwable {

	final String methodName = method.getName();

	if (methodName.equals("getMBeanServer")) {
	    return mbs;
	}

	if (methodName.equals("setMBeanServer")) {
	    if (args[0] == null)
		throw new IllegalArgumentException("Null MBeanServer");
	    if (mbs != null)
		throw new IllegalArgumentException("MBeanServer object " +
						   "already initialized");
	    mbs = (MBeanServer) args[0];
	    return null;
	}

	if (methodName.equals("getAttribute") && exception != null) {
	    throw exception;
	}

	return method.invoke(mbs, args);
    }

    public void setGetAttributeException(Exception exception) {
        this.exception = exception;
    }

    private Exception exception;
    private MBeanServer mbs;
}