| /* Timer.java -- |
| Copyright (C) 2002, 2004, 2005, 2006, Free Software Foundation, Inc. |
| |
| 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. |
| |
| GNU Classpath 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 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 |
| conditions of the GNU General Public License cover the whole |
| 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 |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package javax.swing; |
| |
| import java.awt.event.ActionEvent; |
| import java.awt.event.ActionListener; |
| import java.io.Serializable; |
| import java.util.EventListener; |
| |
| import javax.swing.event.EventListenerList; |
| |
| /** |
| * Fires one or more action events after the specified delay. This is |
| * a specialised version of <code>java.util.Timer</code> just for |
| * firing <code>ActionEvent</code>s. All Timers share one (daemon) |
| * Thread (or java.util.Timer). All events are fired from the event |
| * queue. |
| * |
| * @author Ronald Veldema |
| * @author Audrius Meskauskas (audriusa@Bionformatics.org) - bug fixes |
| * and documentation comments |
| */ |
| public class Timer |
| implements Serializable |
| { |
| /** |
| * Given to the shared java.util.Timer to (possibly repeatedly) call |
| * queueEvent(). |
| */ |
| private class Task extends java.util.TimerTask |
| { |
| public void run() |
| { |
| if (logTimers) |
| System.out.println("javax.swing.Timer -> queueEvent()"); |
| queueEvent(); |
| |
| if (!repeats) |
| task = null; |
| } |
| } |
| |
| /** |
| * 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(); |
| } |
| }; |
| |
| /** |
| * The static java.util.Timer daemon which will be used to schedule |
| * all javax.swing.Timer.Task objects. The daemon will always be |
| * running, even if there's no task scheduled in it. |
| */ |
| private static java.util.Timer timer = new java.util.Timer("swing.Timer", |
| true); |
| |
| /** |
| * 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; |
| |
| /** |
| * 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; |
| |
| /** |
| * The task that calls queueEvent(). When null this Timer is stopped. |
| * This is package private to avoid synthetic accessor method. |
| */ |
| Task task; |
| |
| /** |
| * 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) |
| { |
| delay = d; |
| initialDelay = d; |
| |
| if (listener != null) |
| addActionListener(listener); |
| } |
| |
| /** |
| * 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 ActionListener[] getActionListeners() |
| { |
| return (ActionListener[]) listenerList.getListeners(ActionListener.class); |
| } |
| |
| /** |
| * 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 void setCoalesce(boolean c) |
| { |
| coalesce = c; |
| } |
| |
| /** |
| * 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() |
| { |
| return coalesce; |
| } |
| |
| /** |
| * 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) |
| { |
| return listenerList.getListeners(listenerType); |
| } |
| |
| /** |
| * 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) |
| { |
| 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 logTimers; |
| } |
| |
| /** |
| * 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 |
| * |
| * @throws IllegalArgumentException if <code>d</code> is less than zero. |
| */ |
| public void setDelay(int d) |
| { |
| if (d < 0) |
| throw new IllegalArgumentException("Invalid delay: " + d); |
| delay = d; |
| } |
| |
| /** |
| * Get the delay between firing the subsequent events. |
| * |
| * @return The delay between subsequent events, in milliseconds |
| */ |
| public int getDelay() |
| { |
| return delay; |
| } |
| |
| /** |
| * 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 |
| * |
| * @throws IllegalArgumentException if <code>i</code> is less than zero. |
| */ |
| public void setInitialDelay(int i) |
| { |
| if (i < 0) |
| throw new IllegalArgumentException("Invalid initial delay: " + 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) |
| { |
| repeats = r; |
| } |
| |
| /** |
| * 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() |
| { |
| 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 task != null; |
| } |
| |
| /** |
| * 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() |
| { |
| Task t = task; |
| if (t == null) |
| { |
| t = new Task(); |
| if (isRepeats()) |
| timer.schedule(t, getInitialDelay(), getDelay()); |
| else |
| timer.schedule(t, getInitialDelay()); |
| task = t; |
| } |
| } |
| |
| /** |
| * Stop firing the action events. |
| */ |
| public void stop() |
| { |
| Task t = task; |
| if (t != null) |
| { |
| t.cancel(); |
| task = null; |
| } |
| } |
| |
| /** |
| * 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. |
| */ |
| void queueEvent() |
| { |
| synchronized(queueLock) |
| { |
| queue++; |
| if (queue == 1) |
| SwingUtilities.invokeLater(drainer); |
| } |
| } |
| } |