001/*
002  GRANITE DATA SERVICES
003  Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004
005  This file is part of Granite Data Services.
006
007  Granite Data Services is free software; you can redistribute it and/or modify
008  it under the terms of the GNU Library General Public License as published by
009  the Free Software Foundation; either version 2 of the License, or (at your
010  option) any later version.
011
012  Granite Data Services is distributed in the hope that it will be useful, but
013  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014  FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015  for more details.
016
017  You should have received a copy of the GNU Library General Public License
018  along with this library; if not, see <http://www.gnu.org/licenses/>.
019*/
020
021package org.granite.gravity;
022
023import java.util.concurrent.atomic.AtomicBoolean;
024
025/**
026 * @author Franck WOLFF
027 */
028public abstract class AsyncChannelRunner implements Runnable {
029
030        protected final Channel channel;
031        private final AtomicBoolean queued = new AtomicBoolean(false);
032        
033        public AsyncChannelRunner(Channel channel) {
034                this.channel = channel;
035        }
036        
037        public final boolean queue(Gravity gravity) {
038                if (queued.getAndSet(true))
039                        return false;
040                gravity.execute(this);
041                return true;
042        }
043        
044        public final void reset() {
045                queued.set(false);
046        }
047        
048        protected abstract void doRun();
049        
050        public final void run() {
051                try {
052                        doRun();
053                }
054                finally {
055                        queued.set(false);
056                }
057        }
058
059        @Override
060        public boolean equals(Object obj) {
061                return getClass().isInstance(obj) && channel.equals(((AsyncChannelRunner)obj).channel);
062        }
063
064        @Override
065        public int hashCode() {
066                return channel.hashCode();
067        }
068}