EventDispatchThread.java

/* EventDispatchThread.java -
   Copyright (C) 2000, 2002, 2004  Free Software Foundation

This file is part of GNU Classpath.

GNU Classpath 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, or (at your option)
any later version.

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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.

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along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
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or based on this library.  If you modify this library, you may extend
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package java.awt;

/**
 * @author Bryce McKinlay
 * @status believed complete, but untested.
 */
class EventDispatchThread extends Thread
{
  /**
   * The default priority when no property has been set.
   */
  private static final int DEFAULT_PRIORITY = NORM_PRIORITY + 1;

  private static int dispatchThreadNum;

  private EventQueue queue;

  EventDispatchThread(EventQueue queue)
  {
    super();
    setName("AWT-EventQueue-" + ++dispatchThreadNum);
    this.queue = queue;

    int priority = DEFAULT_PRIORITY;
    try
      {
        String priorityString =
          System.getProperty("gnu.awt.dispatchthread.priority");
        if (priorityString != null)
          {
            priority = Integer.parseInt(priorityString);
          }
      }
    catch (NumberFormatException ex)
      {
        // Ignore and use default.
      }
    setPriority(priority);

    // Make sure that an event dispatch thread is never a daemon thread.
    setDaemon(false);
  }

  public void run()
  {
    while (true)
      {
        try
        {
          AWTEvent evt = queue.getNextEvent();
          queue.dispatchEvent(evt);
        }
        catch (ThreadDeath death)
        {
          // If someone wants to kill us, let them.
          return;
        }
        catch (InterruptedException ie)
        {
          // We are interrupted when we should finish executing
          return;
        }
        catch (Throwable x)
        {
          System.err.println("Exception during event dispatch:");
          x.printStackTrace(System.err);
        }
      }
  }
}