/*
* This file is part of muCommander, http://www.mucommander.com
* Copyright (C) 2002-2016 Maxence Bernard
*
* muCommander 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 3 of the License, or
* (at your option) any later version.
*
* muCommander 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, see <http://www.gnu.org/licenses/>.
*/
package com.mucommander.ui.main.tree;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A class that monitors IOThread if it is running or has been blocked.
* This class maintains a list of tasks to execute and a thread that
* executes these tasks. It checks periodically if the IOThread is running.
* If IOThread has been blocked then it's killed and a new IOThread is
* instantiated. Then the next task from the list will be executed.
* @author Mariusz Jakubowski
*
*/
public class AbstractIOThreadManager extends Thread {
private static final Logger LOGGER = LoggerFactory.getLogger(AbstractIOThreadManager.class);
/** a queue with tasks to execute */
protected final List<Runnable> queue = Collections.synchronizedList(new ArrayList<Runnable>());
/** a thread that executes tasks */
protected IOThread ioThread;
/** a time after i/o thread is marked as blocked */
protected long blockThreshold;
/**
* Creates a new monitoring thread.
* @param name a name of this thread
* @param blockThreshold a time after an i/o task is marked as blocked [ms]
*/
public AbstractIOThreadManager(String name, long blockThreshold) {
super(name);
this.blockThreshold = blockThreshold;
ioThread = new IOThread(queue, blockThreshold);
ioThread.start();
}
/**
* Adds new task to execute. A task is an instance of Runnable interface.
* A proper exception handling within the Runnable instance have to be implemented.
* If this task rises an exception, this exception is printed to stderr.
* @param task a task to be executed
*/
public void addTask(Runnable task) {
queue.add(task);
synchronized(ioThread) {
ioThread.notify();
}
}
@Override
public void run() {
while (!interrupted()) {
synchronized (queue) {
if (ioThread.isBlocked()) {
LOGGER.debug("Killing IOThread " + ioThread);
ioThread.interrupt();
ioThread = new IOThread(queue, blockThreshold);
ioThread.start();
}
}
try {
sleep(blockThreshold);
} catch (InterruptedException e) {
break;
}
}
ioThread.interrupt();
}
}