com.fusesource.forge.jmstest.threading.LimitedTimeScheduledExecutor.java Source code

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Here is the source code for com.fusesource.forge.jmstest.threading.LimitedTimeScheduledExecutor.java

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/*
 * Copyright (C) 2009, Progress Software Corporation and/or its
 * subsidiaries or affiliates.  All rights reserved.
 *
 * 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 com.fusesource.forge.jmstest.threading;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class LimitedTimeScheduledExecutor implements Runnable, Releaseable {

    private String name;

    private long duration = 300;
    private long interval = 5;
    private Runnable task;

    private ScheduledThreadPoolExecutor executor;
    private Thread controlThread;

    private boolean isRunning = false;

    private Object lock = new Object();
    CountDownLatch latch;
    List<CountDownLatch> waiting;

    public LimitedTimeScheduledExecutor() {
        waiting = new ArrayList<CountDownLatch>();
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        if (name == null) {
            name = this.getClass().getName() + "-" + UUID.randomUUID();
        }
        return name;
    }

    public long getDuration() {
        return duration;
    }

    public void setDuration(long duration) {
        this.duration = duration;
    }

    public long getInterval() {
        return interval;
    }

    public void setInterval(long interval) {
        this.interval = interval;
    }

    public void setTask(Runnable task) {
        this.task = task;
    }

    public Runnable getTask() {
        return task;
    }

    public ReleaseManager getReleaseManager() {
        return ReleaseManager.getInstance();
    }

    public void start() {
        synchronized (lock) {
            if (isRunning) {
                return;
            }
            controlThread = new Thread(this, getName());
            controlThread.start();
            isRunning = true;
        }
    }

    public void waitUntilFinished() {
        synchronized (lock) {
            if (!isRunning) {
                return;
            }
        }
        CountDownLatch latch = new CountDownLatch(1);
        synchronized (waiting) {
            waiting.add(latch);
        }
        try {
            latch.await();
        } catch (InterruptedException e) {
        }
    }

    public void run() {
        log().info(getClass().getSimpleName() + " " + getName() + " starting.");

        getReleaseManager().register(this);

        executor = new ScheduledThreadPoolExecutor(1);
        executor.scheduleAtFixedRate(getTask(), 0, getInterval(), TimeUnit.SECONDS);

        latch = new CountDownLatch(1);

        new ScheduledThreadPoolExecutor(1).schedule(new Runnable() {

            public void run() {
                try {
                    release();
                } catch (Exception e) {
                }
            }
        }, duration, TimeUnit.SECONDS);

        try {
            latch.await();
        } catch (InterruptedException ie) {
            try {
                release();
            } catch (Exception e) {
            }
        }
        isRunning = false;
        log().info(getClass().getSimpleName() + " " + getName() + " finished.");
    }

    public void release() {
        synchronized (lock) {
            if (!isRunning) {
                return;
            }
            if (executor != null) {
                log().debug("Closing " + getName());
                executor.shutdown();
                executor = null;
            }

            synchronized (waiting) {
                while (waiting.size() > 0) {
                    CountDownLatch l = waiting.remove(0);
                    l.countDown();
                }
            }
            latch.countDown();
            getReleaseManager().deregister(this);
        }
    }

    private Log log() {
        return LogFactory.getLog(this.getClass());
    }
}