/*
 *
 * Copyright (c) 2006 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package org.apache.qpid.server.cluster.handler;

import org.apache.qpid.AMQException;
import org.apache.qpid.framing.AMQMethodBody;
import org.apache.qpid.server.exchange.ExchangeRegistry;
import org.apache.qpid.server.protocol.AMQMethodEvent;
import org.apache.qpid.server.protocol.AMQProtocolSession;
import org.apache.qpid.server.queue.QueueRegistry;
import org.apache.qpid.server.state.AMQStateManager;
import org.apache.qpid.server.state.StateAwareMethodListener;

public class WrappedListener<T extends AMQMethodBody> implements StateAwareMethodListener<T>
{
    private final StateAwareMethodListener<T> _primary;
    private final StateAwareMethodListener _post;
    private final StateAwareMethodListener _pre;

    WrappedListener(StateAwareMethodListener<T> primary, StateAwareMethodListener  pre, StateAwareMethodListener post)
    {
        _pre = check(pre);
        _post = check(post);
        _primary = check(primary);
    }

    public void methodReceived(AMQStateManager stateMgr, QueueRegistry queues, ExchangeRegistry exchanges, AMQProtocolSession session, AMQMethodEvent<T> evt) throws AMQException
    {
        _pre.methodReceived(stateMgr, queues, exchanges, session, evt);
        _primary.methodReceived(stateMgr, queues, exchanges, session, evt);
        _post.methodReceived(stateMgr, queues, exchanges, session, evt);
    }

    private static <T extends AMQMethodBody> StateAwareMethodListener<T> check(StateAwareMethodListener<T> in)
    {
        return in == null ? new NullListener<T>() : in;
    }
}
