QueueManager.java

//
// This file is part of the OpenNMS(R) Application.
//
// OpenNMS(R) is Copyright (C) 2006 The OpenNMS Group, Inc. All rights
// reserved.
// OpenNMS(R) is a derivative work, containing both original code, included
// code and modified
// code that was published under the GNU General Public License. Copyrights
// for modified
// and included code are below.
//
// OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
//
// Modifications:
//
// 2008 Mar 20: System.out.println -> log().info. - dj@opennms.org
//
// Original code base Copyright (C) 1999-2001 Oculan Corp. All rights
// reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// For more information contact:
// OpenNMS Licensing <license@opennms.org>
// http://www.opennms.org/
// http://www.opennms.com/
//
package org.infosec.ismp.syslogd;

import org.infosec.ismp.model.event.Event;
import org.infosec.ismp.util.ThreadCategory;
import org.infosec.ismp.util.queue.FifoQueue;
import org.infosec.ismp.util.queue.FifoQueueException;
import org.infosec.ismp.util.queue.FifoQueueImpl;

/**
 * 
 */
public class QueueManager {

	FifoQueue<Event> m_backlogQ = new FifoQueueImpl<Event>();

	Event ret;

	public synchronized void putInQueue(Event re) {
		// This synchronized method places a message in the queue
		// Category log = ThreadCategory.getInstance(this.getClass());

		ret = re;

		try {
			m_backlogQ.add(ret);

		} catch (FifoQueueException e) {
			// log.debug("Caught an exception adding to queue");
		} catch (InterruptedException e) {
			// Error handling by ignoring the problem.
		}
		// wake up getByteFromQueue() if it has invoked wait().
		notify();
	}// end method putByteInQueue()

	// -----------------------------------------------------//

	public synchronized Event getFromQueue() {
		// This synchronized method removes a message from the queue
		ThreadCategory log = ThreadCategory.getInstance(this.getClass());

		try {
			while (m_backlogQ.isEmpty()) {
				wait();
			}// end while
		} catch (InterruptedException E) {
			log.info("InterruptedException: " + E, E);
		}// end catch block

		// get the byte from the queue

		try {
			ret = m_backlogQ.remove();
		} catch (FifoQueueException e) {
			log.debug("FifoQueue exception " + e);
		} catch (InterruptedException e) {
			log.debug("Interrupted exception " + e);
		}

		// wake up putByteInQueue() if it has invoked wait().
		notify();
		return ret;
	}// end getByteFromQueue()

}