A pool of work threads
/*
* WorkThreadPool.java - Background thread pool that does stuff
* :tabSize=8:indentSize=8:noTabs=false:
* :folding=explicit:collapseFolds=1:
*
* Copyright (C) 2000 Slava Pestov
*
* 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 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.
*/
//{{{ Imports
import java.util.EventListener;
import javax.swing.SwingUtilities;
import javax.swing.event.EventListenerList;
//}}}
/**
* A pool of work threads.
*
* @author Slava Pestov
* @version $Id: WorkThreadPool.java 12504 2008-04-22 23:12:43Z ezust $
* @see org.gjt.sp.util.WorkThread
* @since jEdit 2.6pre1
*/
public class WorkThreadPool {
// {{{ WorkThreadPool constructor
/**
* Creates a new work thread pool with the specified number of work threads.
*
* @param name
* The thread name prefix
* @param count
* The number of work threads
*/
public WorkThreadPool(String name, int count) {
listenerList = new EventListenerList();
if (count != 0) {
threadGroup = new ThreadGroup(name);
threads = new WorkThread[count];
for (int i = 0; i < threads.length; i++) {
threads[i] = new WorkThread(this, threadGroup, name + " #" + (i + 1));
}
}
} // }}}
// {{{ start() method
/**
* Starts all the threads in this thread pool.
*/
public void start() {
/* not really needed since threads don't start until after */
synchronized (lock) {
started = true;
if (awtRequestCount != 0 && requestCount == 0)
queueAWTRunner();
}
if (threads != null) {
for (int i = 0; i < threads.length; i++) {
threads[i].start();
}
}
} // }}}
// {{{ addWorkRequest() method
/**
* Adds a work request to the queue.
*
* @param run
* The runnable
* @param inAWT
* If true, will be executed in AWT thread. Otherwise, will be
* executed in work thread
*/
public void addWorkRequest(Runnable run, boolean inAWT) {
if (threads == null) {
run.run();
return;
}
synchronized (lock) {
// {{{ if there are no requests, execute AWT requests immediately
if (started && inAWT && requestCount == 0 && awtRequestCount == 0) {
// Log.log(Log.DEBUG,this,"AWT immediate: " + run);
if (SwingUtilities.isEventDispatchThread())
run.run();
else
SwingUtilities.invokeLater(run);
return;
} // }}}
Request request = new Request(run);
// {{{ Add to AWT queue...
if (inAWT) {
if (firstAWTRequest == null && lastAWTRequest == null)
firstAWTRequest = lastAWTRequest = request;
else {
lastAWTRequest.next = request;
lastAWTRequest = request;
}
awtRequestCount++;
// if no requests are running, requestDone()
// will not be called, so we must queue the
// AWT runner ourselves.
if (started && requestCount == 0)
queueAWTRunner();
} // }}}
// {{{ Add to work thread queue...
else {
if (firstRequest == null && lastRequest == null)
firstRequest = lastRequest = request;
else {
lastRequest.next = request;
lastRequest = request;
}
requestCount++;
} // }}}
lock.notifyAll();
}
} // }}}
// {{{ waitForRequests() method
/**
* Waits until all requests are complete.
*/
public void waitForRequests() {
if (threads == null)
return;
synchronized (waitForAllLock) {
while (requestCount != 0) {
try {
waitForAllLock.wait();
} catch (InterruptedException ie) {
}
}
}
if (SwingUtilities.isEventDispatchThread()) {
// do any queued AWT runnables
doAWTRequests();
} else {
try {
SwingUtilities.invokeAndWait(new RunRequestsInAWTThread());
} catch (Exception e) {
}
}
} // }}}
// {{{ getRequestCount() method
/**
* Returns the number of pending requests.
*
* @return the pending request count
*/
public int getRequestCount() {
return requestCount;
} // }}}
// {{{ getThreadCount() method
/**
* Returns the number of threads in this pool.
*
* @return the thread count
*/
public int getThreadCount() {
if (threads == null)
return 0;
else
return threads.length;
} // }}}
// {{{ getThread() method
/**
* Returns the specified thread.
*
* @param index
* The index of the thread
* @return a WorkThread
*/
public WorkThread getThread(int index) {
return threads[index];
} // }}}
// {{{ addProgressListener() method
/**
* Adds a progress listener to this thread pool.
*
* @param listener
* The listener
*/
public void addProgressListener(WorkThreadProgressListener listener) {
listenerList.add(WorkThreadProgressListener.class, listener);
} // }}}
// {{{ removeProgressListener() method
/**
* Removes a progress listener from this thread pool.
*
* @param listener
* The listener
*/
public void removeProgressListener(WorkThreadProgressListener listener) {
listenerList.remove(WorkThreadProgressListener.class, listener);
} // }}}
// {{{ Package-private members
final Object lock = new Object();
final Object waitForAllLock = new Object();
// {{{ fireStatusChanged() method
void fireStatusChanged(WorkThread thread) {
final Object[] listeners = listenerList.getListenerList();
if (listeners.length != 0) {
int index = 0;
for (int i = 0; i < threads.length; i++) {
if (threads[i] == thread) {
index = i;
break;
}
}
for (int i = listeners.length - 2; i >= 0; i--) {
if (listeners[i] == WorkThreadProgressListener.class) {
((WorkThreadProgressListener) listeners[i + 1]).statusUpdate(WorkThreadPool.this, index);
}
}
}
} // }}}
// {{{ fireProgressChanged() method
void fireProgressChanged(WorkThread thread) {
final Object[] listeners = listenerList.getListenerList();
if (listeners.length != 0) {
int index = 0;
for (int i = 0; i < threads.length; i++) {
if (threads[i] == thread) {
index = i;
break;
}
}
for (int i = listeners.length - 2; i >= 0; i--) {
if (listeners[i] == WorkThreadProgressListener.class) {
((WorkThreadProgressListener) listeners[i + 1])
.progressUpdate(WorkThreadPool.this, index);
}
}
}
} // }}}
// {{{ requestDone() method
void requestDone() {
synchronized (lock) {
requestCount--;
if (requestCount == 0 && firstAWTRequest != null)
queueAWTRunner();
}
} // }}}
// {{{ getNextRequest() method
Request getNextRequest() {
synchronized (lock) {
Request request = firstRequest;
if (request == null)
return null;
firstRequest = firstRequest.next;
if (firstRequest == null)
lastRequest = null;
if (request.alreadyRun)
throw new InternalError("AIEE!!! Request run twice!!! " + request.run);
request.alreadyRun = true;
/*
* StringBuffer buf = new StringBuffer("request queue is now: "); Request
* _request = request.next; while(_request != null) {
* buf.append(_request.id); if(_request.next != null) buf.append(",");
* _request = _request.next; } Log.log(Log.DEBUG,this,buf.toString());
*/
return request;
}
} // }}}
// }}}
// {{{ Private members
// {{{ Instance variables
private boolean started;
private ThreadGroup threadGroup;
private WorkThread[] threads;
// Request queue
private Request firstRequest;
private Request lastRequest;
private int requestCount;
// AWT thread magic
private boolean awtRunnerQueued;
private Request firstAWTRequest;
private Request lastAWTRequest;
private int awtRequestCount;
private EventListenerList listenerList;
// }}}
// {{{ doAWTRequests() method
/** Must always be called with the lock held. */
private void doAWTRequests() {
while (requestCount == 0 && firstAWTRequest != null) {
doAWTRequest(getNextAWTRequest());
}
} // }}}
// {{{ doAWTRequest() method
/**
* Must always be called with the lock held.
*
* @param request
* the request to run
*/
private void doAWTRequest(Request request) {
// Log.log(Log.DEBUG,this,"Running in AWT thread: " + request);
try {
request.run.run();
} catch (Throwable t) {
}
awtRequestCount--;
} // }}}
// {{{ queueAWTRunner() method
/** Must always be called with the lock held. */
private void queueAWTRunner() {
if (!awtRunnerQueued) {
awtRunnerQueued = true;
SwingUtilities.invokeLater(new RunRequestsInAWTThread());
// Log.log(Log.DEBUG,this,"AWT runner queued");
}
} // }}}
// {{{ getNextAWTRequest() method
private Request getNextAWTRequest() {
Request request = firstAWTRequest;
firstAWTRequest = firstAWTRequest.next;
if (firstAWTRequest == null)
lastAWTRequest = null;
if (request.alreadyRun)
throw new InternalError("AIEE!!! Request run twice!!! " + request.run);
request.alreadyRun = true;
/*
* StringBuffer buf = new StringBuffer("AWT request queue is now: ");
* Request _request = request.next; while(_request != null) {
* buf.append(_request.id); if(_request.next != null) buf.append(",");
* _request = _request.next; } Log.log(Log.DEBUG,this,buf.toString());
*/
return request;
} // }}}
// }}}
static int ID;
// {{{ Request class
static class Request {
int id = ++ID;
Runnable run;
boolean alreadyRun;
Request next;
Request(Runnable run) {
this.run = run;
}
public String toString() {
return "[id=" + id + ",run=" + run + "]";
}
} // }}}
// {{{ RunRequestsInAWTThread class
class RunRequestsInAWTThread implements Runnable {
public void run() {
synchronized (lock) {
awtRunnerQueued = false;
if (requestCount == 0)
doAWTRequests();
}
}
} // }}}
}
/*
* WorkThread.java - Background thread that does stuff Copyright (C) 2000 Slava
* Pestov
*
* 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 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.
*/
/**
* Services work requests in the background.
*
* @author Slava Pestov
* @version $Id: WorkThread.java 12504 2008-04-22 23:12:43Z ezust $
*/
class WorkThread extends Thread implements ThreadAbortMonitor {
public WorkThread(WorkThreadPool pool, ThreadGroup group, String name) {
super(group, name);
// so that jEdit doesn't exit with no views open automatically
// setDaemon(true);
setPriority(Thread.MIN_PRIORITY);
this.pool = pool;
}
/**
* Sets if the current request can be aborted. If set to true and already
* aborted, the thread will be stopped
*
* @param abortable
* true if the WorkThread is abortable
* @since jEdit 2.6pre1
*/
public void setAbortable(boolean abortable) {
synchronized (abortLock) {
this.abortable = abortable;
if (aborted)
stop(new Abort());
}
}
/**
* Returns if the work thread is currently running a request.
*
* @return true if a request is currently running
*/
public boolean isRequestRunning() {
return requestRunning;
}
public boolean isAborted() {
synchronized (abortLock) {
return aborted;
}
}
/**
* Returns the status text.
*
* @return the status label
*/
public String getStatus() {
return status;
}
/**
* Sets the status text.
*
* @param status
* the new status of the thread
* @since jEdit 2.6pre1
*/
public void setStatus(String status) {
this.status = status;
pool.fireProgressChanged(this);
}
/**
* Returns the progress value.
*
* @return the progress value
*/
public int getProgressValue() {
return progressValue;
}
/**
* Sets the progress value.
*
* @param progressValue
* the new progress value
* @since jEdit 2.6pre1
*/
public void setProgressValue(int progressValue) {
this.progressValue = progressValue;
pool.fireProgressChanged(this);
}
/**
* Returns the progress maximum.
*
* @return the maximum value of the progression
*/
public int getProgressMaximum() {
return progressMaximum;
}
/**
* Sets the maximum progress value.
*
* @param progressMaximum
* the maximum value of the progression
* @since jEdit 2.6pre1
*/
public void setProgressMaximum(int progressMaximum) {
this.progressMaximum = progressMaximum;
pool.fireProgressChanged(this);
}
/**
* Aborts the currently running request, if allowed.
*
* @since jEdit 2.6pre1
*/
public void abortCurrentRequest() {
synchronized (abortLock) {
if (abortable && !aborted)
stop(new Abort());
aborted = true;
}
}
public void run() {
for (;;) {
doRequests();
}
}
// private members
private WorkThreadPool pool;
private final Object abortLock = new Object();
private boolean requestRunning;
private boolean abortable;
private boolean aborted;
private String status;
private int progressValue;
private int progressMaximum;
private void doRequests() {
WorkThreadPool.Request request;
for (;;) {
request = pool.getNextRequest();
if (request == null)
break;
else {
requestRunning = true;
pool.fireStatusChanged(this);
doRequest(request);
requestRunning = false;
}
}
pool.fireStatusChanged(this);
synchronized (pool.waitForAllLock) {
// notify a running waitForRequests() method
pool.waitForAllLock.notifyAll();
}
synchronized (pool.lock) {
// wait for more requests
try {
pool.lock.wait();
} catch (InterruptedException ie) {
}
}
}
private void doRequest(WorkThreadPool.Request request) {
try {
request.run.run();
} catch (Throwable t) {
} finally {
synchronized (abortLock) {
aborted = abortable = false;
}
status = null;
progressValue = progressMaximum = 0;
pool.requestDone();
pool.fireStatusChanged(this);
}
}
public static class Abort extends Error {
public Abort() {
super("Work request aborted");
}
}
}
/*
* ThreadAbortMonitor.java - Thread Abort Monitor
* :tabSize=8:indentSize=8:noTabs=false: :folding=explicit:collapseFolds=1:
*
* Copyright (C) 2006 Matthieu Casanova
*
* 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 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.
*/
/**
* @author Matthieu Casanova
* @author $Id: VFS.java 7129 2006-09-25 20:05:57Z kpouer $
*/
interface ThreadAbortMonitor {
boolean isAborted();
}
/*
* WorkThreadProgressListener.java - Progress listener Copyright (C) 2000 Slava
* Pestov
*
* 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 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.
*/
/**
* A work thread execution progress listener.
*
* @since jEdit 2.6pre1
*/
interface WorkThreadProgressListener extends EventListener {
// status message changed, operation started, operation ends, ...
void statusUpdate(WorkThreadPool threadPool, int threadIndex);
// progress bar value change
void progressUpdate(WorkThreadPool threadPool, int threadIndex);
}
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