X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=libjava%2Fjavax%2Fswing%2FTimer.java;h=eac5832a381be05ba24661b9485811392d48fcf0;hp=fd88351f417eb4607823a8df0673bc139a426706;hb=f8e976477ab53b06a7cb0edbe59fb6ac7957ee65;hpb=848ad1d5b17a69b163abc0986cd33f6c64b921f1

diff --git a/libjava/javax/swing/Timer.java b/libjava/javax/swing/Timer.java
index fd88351f417..eac5832a381 100644
--- a/libjava/javax/swing/Timer.java
+++ b/libjava/javax/swing/Timer.java
@@ -1,5 +1,5 @@
-/* Timer.java -- 
-   Copyright (C) 2002, 2004  Free Software Foundation, Inc.
+/* Timer.java --
+   Copyright (C) 2002, 2004, 2005  Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -45,134 +45,436 @@ import java.util.EventListener;
 
 import javax.swing.event.EventListenerList;
 
-public class Timer implements Serializable
+/**
+ * Fires one or more action events after the specified delay.
+ * @author Ronald Veldema
+ * @author Audrius Meskauskas (audriusa@Bionformatics.org) - bug fixes
+ * and documentation comments
+ */
+public class Timer
+  implements Serializable
 {
-  protected EventListenerList listenerList = new EventListenerList();
-  
-  int ticks;
-  static boolean verbose;
-  boolean running;
-  boolean repeat_ticks = true;
-  long interval, init_delay;
-    
-  class Waker extends Thread
+  /**
+   * The timer thread
+   */
+  private class Waker
+    extends Thread
   {
+    /**
+     * Fires events, pausing for required intervals.
+     */
     public void run()
     {
       running = true;
-      try {
-	sleep(init_delay);
-		
-	while (running)
-	  {
-	    sleep(interval);
-
-	    if (verbose)
-	      {
-		System.out.println("javax.swing.Timer -> clocktick");
-	      }
-
-	    ticks++;
-	    fireActionPerformed();
-  
-	    if (! repeat_ticks)
-	      break;
-	  }
-	running = false;
-      } catch (Exception e) {
-	System.out.println("swing.Timer::" + e);
-      }
+      try
+        {
+          sleep(initialDelay);
+
+          while (running)
+            {
+              try
+                {
+                  sleep(delay);
+                }
+              catch (InterruptedException e)
+                {
+                  return;
+                }
+              queueEvent();
+
+              if (logTimers)
+                System.out.println("javax.swing.Timer -> clocktick");
+
+              if ( ! repeats)
+                break;
+            }
+          running = false;
+        }
+      catch (Exception e)
+        {
+        }
     }
   }
 
-  public void addActionListener(ActionListener listener)
-  {
-    listenerList.add (ActionListener.class, listener);
-  }
-  
-  public void removeActionListener(ActionListener listener)
+  /**
+   * Use serialVersionUID for interoperability.
+   */
+  private static final long serialVersionUID = -1116180831621385484L;
+
+  /**
+   * The encloding class, used with {@link SwingUtilities#invokeLater}
+   * to invoke the {@link #drainEvents()}.
+   */
+  private Runnable drainer = new Runnable()
+    {
+      public void run()
+      {
+        drainEvents();
+      }
+    };
+
+  /**
+   * If <code>true</code>, the timer prints a message to
+   * {@link System#out} when firing each event.
+   */
+  static boolean logTimers;
+
+  /**
+   * A field to store all listeners who are listening to this timer.
+   */
+  protected EventListenerList listenerList = new EventListenerList();
+
+  /**
+   * <code>true</code> if the timer coalesces events.
+   */
+  boolean coalesce = true;
+
+  /**
+   * <code>true</code> if the timer is firing repetetive events.
+   */
+  boolean repeats = true;
+
+  /**
+   * <code>true</code> if the timer is currently active, firing events
+   * as scheduled.
+   */
+  boolean running;
+
+  /**
+   * The delay between subsequent repetetive events.
+   */
+  int delay;
+
+  /**
+   * The initial delay before the first event.
+   */
+  int initialDelay;
+
+  /**
+   * The number of events that have been already fired by this timer.
+   * This is used as a numeric identifier for the next event that would
+   * be fired.
+   */
+  int ticks;
+
+  /**
+   * Stores the thread that posts events to the queue at required time
+   * intervals.
+   */
+  private Waker waker;
+
+  /**
+   * This object manages a "queue" of virtual actionEvents, maintained as a
+   * simple long counter. When the timer expires, a new event is queued,
+   * and a dispatcher object is pushed into the system event queue. When
+   * the system thread runs the dispatcher, it will fire as many
+   * ActionEvents as have been queued, unless the timer is set to
+   * coalescing mode, in which case it will fire only one ActionEvent.
+   */
+  private long queue;
+
+  /**
+   * <code>synchronized(queueLock)</code> replaces
+   * <code>synchronized(queue)</code> that is not supported by this language.
+   */
+  private Object queueLock = new Object();
+
+  /**
+   * Creates a new Timer object.
+   *
+   * @param d the default value for both initial and between event delay, in
+   * milliseconds.
+   * @param listener the first action listener, can be <code>null</code>.
+   */
+  public Timer(int d, ActionListener listener)
   {
-    listenerList.remove (ActionListener.class, listener);
+    delay = d;
+
+    if (listener != null)
+      addActionListener(listener);
   }
 
   /**
-   * @since 1.3
+   * Get the array of action listeners.
+   *
+   * @return the array of action listeners that are listening for the events,
+   * fired by this timer
+   *
+   * @since 1.4
    */
-  public EventListener[] getListeners (Class listenerType)
+  public ActionListener[] getActionListeners()
   {
-    return listenerList.getListeners (listenerType);
+    return (ActionListener[]) listenerList.getListeners(ActionListener.class);
   }
-  
+
   /**
-   * @since 1.4
+   * Sets whether the Timer coalesces multiple pending event firings.
+   * If the coalescing is enabled, the multiple events that have not been
+   * fired on time are replaced by the single event. The events may not
+   * be fired on time if the application is busy.
+   *
+   * @param c <code>true</code> (default) to enable the event coalescing,
+   * <code>false</code> otherwise
    */
-  public ActionListener[] getActionListeners ()
+  public void setCoalesce(boolean c)
   {
-    return (ActionListener[]) listenerList.getListeners (ActionListener.class);
+    coalesce = c;
   }
 
-  protected void fireActionPerformed (ActionEvent event)
+  /**
+   * Checks if the Timer coalesces multiple pending event firings.
+   * If the coalescing is enabled, the multiple events that have not been
+   * fired on time are replaced by the single event. The events may not
+   * be fired on time if the application is busy.
+   *
+   * @return <code>true</code> if the coalescing is enabled,
+   * <code>false</code> otherwise
+   */
+  public boolean isCoalesce()
   {
-    ActionListener[] listeners = getActionListeners();
-    
-    for (int i = 0; i < listeners.length; i++)
-      {
-	listeners [i].actionPerformed (event);
-      }
+    return coalesce;
   }
 
-  void fireActionPerformed ()
+  /**
+   * Get the event listeners of the given type that are listening for the
+   * events, fired by this timer.
+   *
+   * @param listenerType the listener type (for example, ActionListener.class)
+   *
+   * @return the array of event listeners that are listening for the events,
+   * fired by this timer
+   * @since 1.3
+   */
+  public EventListener[] getListeners(Class listenerType)
   {
-    fireActionPerformed (new ActionEvent (this, ticks, "Timer"));
+    return listenerList.getListeners(listenerType);
   }
 
-  public static void setLogTimers(boolean flag)
+  /**
+   * Set the timer logging state. If it is set to <code>true</code>, the
+   * timer prints a message to {@link System#out} when firing each
+   * action event.
+   *
+   * @param lt <code>true</code> if logging is enabled, <code>false</code>
+   * (default value) otherwise
+   */
+  public static void setLogTimers(boolean lt)
   {
-    verbose = flag;
+    logTimers = lt;
   }
 
+  /**
+   * Return the logging state.
+   *
+   * @return <code>true</code> if the timer is printing a message to
+   * {@link System#out}
+   * when firing each action event
+   */
   public static boolean getLogTimers()
   {
-    return verbose;
+    return logTimers;
   }
-    
-  public void setDelay(int delay)
+
+  /**
+   * Set the delay between firing the subsequent events.
+   * This parameter does not change the value of the initial delay before
+   * firing the first event.
+   *
+   * @param d The time gap between the subsequent events, in milliseconds
+   */
+  public void setDelay(int d)
   {
-    interval = delay;
+    delay = d;
   }
 
+  /**
+   * Get the delay between firing the subsequent events.
+   *
+   * @return The delay between subsequent events, in milliseconds
+   */
   public int getDelay()
   {
-    return (int)interval;
+    return delay;
   }
 
-  public void setInitialDelay(int initialDelay)
+  /**
+   * Set the intial delay before firing the first event since calling
+   * the {@link #start()} method. If the initial delay has not been
+   * set, it is assumed having the same value as the delay between the
+   * subsequent events.
+   *
+   * @param i the initial delay, in milliseconds
+   */
+  public void setInitialDelay(int i)
+  {
+    initialDelay = i;
+  }
+
+  /**
+   * Get the intial delay before firing the first event since calling
+   * the {@link #start()} method. If the initial delay has not been
+   * set, returns the same value as {@link #getDelay()}.
+   *
+   * @return the initial delay before firing the first action event.
+   */
+  public int getInitialDelay()
+  {
+    return initialDelay;
+  }
+
+  /**
+   * Enable firing the repetetive events.
+   *
+   * @param r <code>true</code> (default value) to fire repetetive events.
+   * <code>false</code> to fire
+   * only one event after the initial delay
+   */
+  public void setRepeats(boolean r)
   {
-    init_delay = initialDelay;
+    repeats = r;
   }
 
-  public void setRepeats(boolean flag)
+  /**
+   * Check is this timer fires repetetive events.
+   *
+   * @return <code>true</code> if the timer fires repetetive events,
+   * <code>false</code> if it fires
+   * only one event after the initial delay
+   */
+  public boolean isRepeats()
   {
-    repeat_ticks = flag;
+    return repeats;
   }
 
+  /**
+   * Get the timer state.
+   *
+   * @return <code>true</code> if the timer has been started and is firing
+   * the action events as scheduled. <code>false</code>
+   * if the timer is inactive.
+   */
   public boolean isRunning()
   {
     return running;
   }
 
+  /**
+   * Add the action listener
+   *
+   * @param listener the action listener to add
+   */
+  public void addActionListener(ActionListener listener)
+  {
+    listenerList.add(ActionListener.class, listener);
+  }
+
+  /**
+   * Remove the action listener.
+   *
+   * @param listener the action listener to remove
+   */
+  public void removeActionListener(ActionListener listener)
+  {
+    listenerList.remove(ActionListener.class, listener);
+  }
+
+  /**
+   * Cancel all pending tasks and fire the first event after the initial
+   * delay.
+   */
+  public void restart()
+  {
+    stop();
+    start();
+  }
+
+  /**
+   * Start firing the action events.
+   */
   public void start()
   {
     if (isRunning())
-      {
-	System.err.println("attempt to start a running timer");
-	return;
-      }
-    new Waker().start();
+      return;
+    waker = new Waker();
+    waker.start();
   }
 
+  /**
+   * Stop firing the action events.
+   */
   public void stop()
   {
     running = false;
+    if (waker != null)
+      waker.interrupt();
+    synchronized (queueLock)
+      {
+        queue = 0;
+      }
+  }
+
+  /**
+   * Fire the given action event to the action listeners.
+   *
+   * @param event the event to fire
+   */
+  protected void fireActionPerformed(ActionEvent event)
+  {
+    ActionListener[] listeners = getActionListeners();
+
+    for (int i = 0; i < listeners.length; i++)
+      listeners [ i ].actionPerformed(event);
+  }
+
+  /**
+   * Fire the action event, named "Timer" and having the numeric
+   * identifier, equal to the numer of events that have been
+   * already fired before.
+   */
+  void fireActionPerformed()
+  {
+    fireActionPerformed(new ActionEvent(this, ticks++, "Timer"));
+  }
+
+  /**
+   * Fire the queued action events.
+   * In the coalescing mode, a single event is fired as a replacement
+   * for all queued events. In non coalescing mode, a series of
+   * all queued events is fired.
+   * This is package-private to avoid an accessor method.
+   */
+  void drainEvents()
+  {
+    synchronized (queueLock)
+      {
+        if (isCoalesce())
+          {
+            if (queue > 0)
+              fireActionPerformed();
+          }
+        else
+          {
+            while (queue > 0)
+              {
+                fireActionPerformed();
+                queue--;
+              }
+          }
+        queue = 0;
+      }
+  }
+
+  /**
+  * Post a scheduled event to the event queue.
+  * Package-private to avoid an accessor method.
+  */
+  private void queueEvent()
+  {
+    synchronized (queueLock)
+      {
+        queue++;
+        if (queue == 1)
+          SwingUtilities.invokeLater(drainer);
+      }
   }
 }