dk.au.cs.karibu.backend.standard.StandardDaemon.java Source code

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Here is the source code for dk.au.cs.karibu.backend.standard.StandardDaemon.java

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/*
 * Copyright 2013 Henrik Baerbak Christensen, Aarhus University
 *
 * 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 dk.au.cs.karibu.backend.standard;

import java.lang.management.ManagementFactory;

import javax.management.*;

import org.apache.commons.lang.exception.ExceptionUtils;
import org.slf4j.*;

import dk.au.cs.karibu.backend.*;
import dk.au.cs.karibu.monitor.*;

/** The default implementation for a backtier daemon that
 * pulls messages from the MQ and processes them, typically
 * stores them in the database tier.
 * 
 * The actual behavior of the daemon is defined by the
 * delegates which must be configured in advance.
 * 
 * @author Henrik Baerbak Christensen, Aarhus University
 */
public class StandardDaemon {
    private Logger log;
    private String daemonName;
    private Thread receiverThread;

    /** Create a daemon with the given name to handle the
     * provided message receiver endpoint. The daemon is
     * NOT run, use 'startAndJoin' for that, or start it manually
     * using the accessor method for the underlying thread.
     * 
     * @param nameOfDaemon name of daemon used in the log files.
     * @param the message receiver endpoint
     */

    public StandardDaemon(String nameOfDaemon, MessageReceiverEndpoint mre) {
        log = LoggerFactory.getLogger(StandardDaemon.class);
        daemonName = nameOfDaemon;

        receiverThread = new Thread(mre, daemonName + "-ReceiverThread");

        MBeanServer mbs = null;
        MonitoringMBean monitor;

        mbs = ManagementFactory.getPlatformMBeanServer();
        monitor = new Monitoring(mre);
        try {
            String theName2 = "EcoSense:name=" + daemonName + "Monitor";
            ObjectName monitorBeanName = new ObjectName(theName2);
            mbs.registerMBean(monitor, monitorBeanName);
            log.info("Registered JMX bean: " + nameOfDaemon);
        } catch (Exception e) {
            String theTrace = ExceptionUtils.getStackTrace(e);
            log.error("JMX bean exception: " + theTrace);
        }

    }

    /** Start the daemon and join the calling thread.
     * 
     * @throws InterruptedException
     */
    public void startAndJoin() throws InterruptedException {
        // === and turn on the daemon...
        log.info(daemonName + " starting.");

        receiverThread.start();
        receiverThread.join();

        log.info(daemonName + " stopped.");
    }

    /** Return the underlying thread. 
     * @return the thread created.
     */
    public Thread getReceiverThread() {
        return receiverThread;
    }
}