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ActiveMQ example source code file (ServiceSupport.java)

This example ActiveMQ source code file (ServiceSupport.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - ActiveMQ tags/keywords

atomicboolean, atomicboolean, copyonwritearraylist, could, exception, exception, list, logger, reason, service, servicestopper, servicestopper, servicesupport, servicesupport, threading, threads, util

The ActiveMQ ServiceSupport.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.activemq.util;

import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.atomic.AtomicBoolean;

import org.apache.activemq.Service;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * A helper class for working with services together with a useful base class
 * for service implementations.
 * 
 * 
 */
public abstract class ServiceSupport implements Service {
    private static final Logger LOG = LoggerFactory.getLogger(ServiceSupport.class);

    private AtomicBoolean started = new AtomicBoolean(false);
    private AtomicBoolean stopping = new AtomicBoolean(false);
    private AtomicBoolean stopped = new AtomicBoolean(false);
    private List<ServiceListener>serviceListeners = new CopyOnWriteArrayList();

    public static void dispose(Service service) {
        try {
            service.stop();
        } catch (Exception e) {
            LOG.debug("Could not stop service: " + service + ". Reason: " + e, e);
        }
    }

    public void start() throws Exception {
        if (started.compareAndSet(false, true)) {
            boolean success = false;
            try {
                doStart();
                success = true;
            } finally {
                started.set(success);
            }
            for(ServiceListener l:this.serviceListeners) {
                l.started(this);
            }
        }
    }

    public void stop() throws Exception {
        if (stopped.compareAndSet(false, true)) {
            stopping.set(true);
            ServiceStopper stopper = new ServiceStopper();
            try {
                doStop(stopper);
            } catch (Exception e) {
                stopper.onException(this, e);
            }
            stopped.set(true);
            started.set(false);
            stopping.set(false);
            for(ServiceListener l:this.serviceListeners) {
                l.stopped(this);
            }
            stopper.throwFirstException();
        }
    }

    /**
     * @return true if this service has been started
     */
    public boolean isStarted() {
        return started.get();
    }

    /**
     * @return true if this service is in the process of closing
     */
    public boolean isStopping() {
        return stopping.get();
    }

    /**
     * @return true if this service is closed
     */
    public boolean isStopped() {
        return stopped.get();
    }
    
    public void addServiceListener(ServiceListener l) {
        this.serviceListeners.add(l);
    }
    
    public void removeServiceListener(ServiceListener l) {
        this.serviceListeners.remove(l);
    }

    protected abstract void doStop(ServiceStopper stopper) throws Exception;

    protected abstract void doStart() throws Exception;
}

Other ActiveMQ examples (source code examples)

Here is a short list of links related to this ActiveMQ ServiceSupport.java source code file:

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