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| 1 | /* | ||
| 2 | * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. | ||
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | ||
| 4 | * | ||
| 5 | * This code is free software; you can redistribute it and/or modify it | ||
| 6 | * under the terms of the GNU General Public License version 2 only, as | ||
| 7 | * published by the Free Software Foundation. Oracle designates this | ||
| 8 | * particular file as subject to the "Classpath" exception as provided | ||
| 9 | * by Oracle in the LICENSE file that accompanied this code. | ||
| 10 | * | ||
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT | ||
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
| 14 | * version 2 for more details (a copy is included in the LICENSE file that | ||
| 15 | * accompanied this code). | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License version | ||
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, | ||
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | ||
| 20 | * | ||
| 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | ||
| 22 | * or visit www.oracle.com if you need additional information or have any | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | |||
| 26 | |||
| 27 | |||
| 28 | package javax.swing; | ||
| 29 | |||
| 30 | |||
| 31 | |||
| 32 | import java.util.*; | ||
| 33 | import java.util.concurrent.atomic.AtomicBoolean; | ||
| 34 | import java.util.concurrent.locks.*; | ||
| 35 | import java.awt.*; | ||
| 36 | import java.awt.event.*; | ||
| 37 | import java.io.Serializable; | ||
| 38 | import java.io.*; | ||
| 39 | import java.security.AccessControlContext; | ||
| 40 | import java.security.AccessController; | ||
| 41 | import java.security.PrivilegedAction; | ||
| 42 | import javax.swing.event.EventListenerList; | ||
| 43 | |||
| 44 | |||
| 45 | |||
| 46 | /** | ||
| 47 | * Fires one or more {@code ActionEvent}s at specified | ||
| 48 | * intervals. An example use is an animation object that uses a | ||
| 49 | * <code>Timer</code> as the trigger for drawing its frames. | ||
| 50 | *<p> | ||
| 51 | * Setting up a timer | ||
| 52 | * involves creating a <code>Timer</code> object, | ||
| 53 | * registering one or more action listeners on it, | ||
| 54 | * and starting the timer using | ||
| 55 | * the <code>start</code> method. | ||
| 56 | * For example, | ||
| 57 | * the following code creates and starts a timer | ||
| 58 | * that fires an action event once per second | ||
| 59 | * (as specified by the first argument to the <code>Timer</code> constructor). | ||
| 60 | * The second argument to the <code>Timer</code> constructor | ||
| 61 | * specifies a listener to receive the timer's action events. | ||
| 62 | * | ||
| 63 | *<pre> | ||
| 64 | * int delay = 1000; //milliseconds | ||
| 65 | * ActionListener taskPerformer = new ActionListener() { | ||
| 66 | * public void actionPerformed(ActionEvent evt) { | ||
| 67 | * <em>//...Perform a task...</em> | ||
| 68 | * } | ||
| 69 | * }; | ||
| 70 | * new Timer(delay, taskPerformer).start();</pre> | ||
| 71 | * | ||
| 72 | * <p> | ||
| 73 | * {@code Timers} are constructed by specifying both a delay parameter | ||
| 74 | * and an {@code ActionListener}. The delay parameter is used | ||
| 75 | * to set both the initial delay and the delay between event | ||
| 76 | * firing, in milliseconds. Once the timer has been started, | ||
| 77 | * it waits for the initial delay before firing its | ||
| 78 | * first <code>ActionEvent</code> to registered listeners. | ||
| 79 | * After this first event, it continues to fire events | ||
| 80 | * every time the between-event delay has elapsed, until it | ||
| 81 | * is stopped. | ||
| 82 | * <p> | ||
| 83 | * After construction, the initial delay and the between-event | ||
| 84 | * delay can be changed independently, and additional | ||
| 85 | * <code>ActionListeners</code> may be added. | ||
| 86 | * <p> | ||
| 87 | * If you want the timer to fire only the first time and then stop, | ||
| 88 | * invoke <code>setRepeats(false)</code> on the timer. | ||
| 89 | * <p> | ||
| 90 | * Although all <code>Timer</code>s perform their waiting | ||
| 91 | * using a single, shared thread | ||
| 92 | * (created by the first <code>Timer</code> object that executes), | ||
| 93 | * the action event handlers for <code>Timer</code>s | ||
| 94 | * execute on another thread -- the event-dispatching thread. | ||
| 95 | * This means that the action handlers for <code>Timer</code>s | ||
| 96 | * can safely perform operations on Swing components. | ||
| 97 | * However, it also means that the handlers must execute quickly | ||
| 98 | * to keep the GUI responsive. | ||
| 99 | * | ||
| 100 | * <p> | ||
| 101 | * In v 1.3, another <code>Timer</code> class was added | ||
| 102 | * to the Java platform: <code>java.util.Timer</code>. | ||
| 103 | * Both it and <code>javax.swing.Timer</code> | ||
| 104 | * provide the same basic functionality, | ||
| 105 | * but <code>java.util.Timer</code> | ||
| 106 | * is more general and has more features. | ||
| 107 | * The <code>javax.swing.Timer</code> has two features | ||
| 108 | * that can make it a little easier to use with GUIs. | ||
| 109 | * First, its event handling metaphor is familiar to GUI programmers | ||
| 110 | * and can make dealing with the event-dispatching thread | ||
| 111 | * a bit simpler. | ||
| 112 | * Second, its | ||
| 113 | * automatic thread sharing means that you don't have to | ||
| 114 | * take special steps to avoid spawning | ||
| 115 | * too many threads. | ||
| 116 | * Instead, your timer uses the same thread | ||
| 117 | * used to make cursors blink, | ||
| 118 | * tool tips appear, | ||
| 119 | * and so on. | ||
| 120 | * | ||
| 121 | * <p> | ||
| 122 | * You can find further documentation | ||
| 123 | * and several examples of using timers by visiting | ||
| 124 | * <a href="http://java.sun.com/docs/books/tutorial/uiswing/misc/timer.html" | ||
| 125 | * target = "_top">How to Use Timers</a>, | ||
| 126 | * a section in <em>The Java Tutorial.</em> | ||
| 127 | * For more examples and help in choosing between | ||
| 128 | * this <code>Timer</code> class and | ||
| 129 | * <code>java.util.Timer</code>, | ||
| 130 | * see | ||
| 131 | * <a href="http://java.sun.com/products/jfc/tsc/articles/timer/" | ||
| 132 | * target="_top">Using Timers in Swing Applications</a>, | ||
| 133 | * an article in <em>The Swing Connection.</em> | ||
| 134 | * <p> | ||
| 135 | * <strong>Warning:</strong> | ||
| 136 | * Serialized objects of this class will not be compatible with | ||
| 137 | * future Swing releases. The current serialization support is | ||
| 138 | * appropriate for short term storage or RMI between applications running | ||
| 139 | * the same version of Swing. As of 1.4, support for long term storage | ||
| 140 | * of all JavaBeans<sup><font size="-2">TM</font></sup> | ||
| 141 | * has been added to the <code>java.beans</code> package. | ||
| 142 | * Please see {@link java.beans.XMLEncoder}. | ||
| 143 | * | ||
| 144 | * @see java.util.Timer <code>java.util.Timer</code> | ||
| 145 | * | ||
| 146 | * | ||
| 147 | * @author Dave Moore | ||
| 148 | */ | ||
| 149 | public class Timer implements Serializable | ||
| 150 | { | ||
| 151 | /* | ||
| 152 | * NOTE: all fields need to be handled in readResolve | ||
| 153 | */ | ||
| 154 | |||
| 155 | protected EventListenerList listenerList = new EventListenerList(); | ||
| 156 | |||
| 157 | // The following field strives to maintain the following: | ||
| 158 | // If coalesce is true, only allow one Runnable to be queued on the | ||
| 159 | // EventQueue and be pending (ie in the process of notifying the | ||
| 160 | // ActionListener). If we didn't do this it would allow for a | ||
| 161 | // situation where the app is taking too long to process the | ||
| 162 | // actionPerformed, and thus we'ld end up queing a bunch of Runnables | ||
| 163 | // and the app would never return: not good. This of course implies | ||
| 164 | // you can get dropped events, but such is life. | ||
| 165 | // notify is used to indicate if the ActionListener can be notified, when | ||
| 166 | // the Runnable is processed if this is true it will notify the listeners. | ||
| 167 | // notify is set to true when the Timer fires and the Runnable is queued. | ||
| 168 | // It will be set to false after notifying the listeners (if coalesce is | ||
| 169 | // true) or if the developer invokes stop. | ||
| 170 | private transient final AtomicBoolean notify = new AtomicBoolean(false); | ||
| 171 | |||
| 172 | private volatile int initialDelay, delay; | ||
| 173 | private volatile boolean repeats = true, coalesce = true; | ||
| 174 | |||
| 175 | private transient final Runnable doPostEvent; | ||
| 176 | |||
| 177 | private static volatile boolean logTimers; | ||
| 178 | |||
| 179 | private transient final Lock lock = new ReentrantLock(); | ||
| 180 | |||
| 181 | // This field is maintained by TimerQueue. | ||
| 182 | // eventQueued can also be reset by the TimerQueue, but will only ever | ||
| 183 | // happen in applet case when TimerQueues thread is destroyed. | ||
| 184 | // access to this field is synchronized on getLock() lock. | ||
| 185 | transient TimerQueue.DelayedTimer delayedTimer = null; | ||
| 186 | |||
| 187 | private volatile String actionCommand; | ||
| 188 | |||
| 189 | /** | ||
| 190 | * Creates a {@code Timer} and initializes both the initial delay and | ||
| 191 | * between-event delay to {@code delay} milliseconds. If {@code delay} | ||
| 192 | * is less than or equal to zero, the timer fires as soon as it | ||
| 193 | * is started. If <code>listener</code> is not <code>null</code>, | ||
| 194 | * it's registered as an action listener on the timer. | ||
| 195 | * | ||
| 196 | * @param delay milliseconds for the initial and between-event delay | ||
| 197 | * @param listener an initial listener; can be <code>null</code> | ||
| 198 | * | ||
| 199 | * @see #addActionListener | ||
| 200 | * @see #setInitialDelay | ||
| 201 | * @see #setRepeats | ||
| 202 | */ | ||
| 203 | public Timer(int delay, ActionListener listener) { | ||
| 204 | super(); | ||
| 205 | this.delay = delay; | ||
| 206 | this.initialDelay = delay; | ||
| 207 | |||
| 208 | doPostEvent = new DoPostEvent(); | ||
| 209 | |||
| 210 | if (listener != null) { | ||
| 211 | addActionListener(listener); | ||
| 212 | } | ||
| 213 | } | ||
| 214 | |||
| 215 | /* | ||
| 216 | * The timer's AccessControlContext. | ||
| 217 | */ | ||
| 218 | private transient volatile AccessControlContext acc = | ||
| 219 | AccessController.getContext(); | ||
| 220 | |||
| 221 | /** | ||
| 222 | * Returns the acc this timer was constructed with. | ||
| 223 | */ | ||
| 224 | final AccessControlContext getAccessControlContext() { | ||
| 225 | if (acc == null) { | ||
| 226 | throw new SecurityException( | ||
| 227 | "Timer is missing AccessControlContext"); | ||
| 228 | } | ||
| 229 | return acc; | ||
| 230 | } | ||
| 231 | |||
| 232 | /** | ||
| 233 | * DoPostEvent is a runnable class that fires actionEvents to | ||
| 234 | * the listeners on the EventDispatchThread, via invokeLater. | ||
| 235 | * @see Timer#post | ||
| 236 | */ | ||
| 237 | class DoPostEvent implements Runnable | ||
| 238 | { | ||
| 239 | public void run() { | ||
| 240 | if (logTimers) { | ||
| 241 | System.out.println("Timer ringing: " + Timer.this); | ||
| 242 | } | ||
| 243 | if(notify.get()) { | ||
| 244 | fireActionPerformed(new ActionEvent(Timer.this, 0, getActionCommand(), | ||
| 245 | System.currentTimeMillis(), | ||
| 246 | 0)); | ||
| 247 | if (coalesce) { | ||
| 248 | cancelEvent(); | ||
| 249 | } | ||
| 250 | } | ||
| 251 | } | ||
| 252 | |||
| 253 | Timer getTimer() { | ||
| 254 | return Timer.this; | ||
| 255 | } | ||
| 256 | } | ||
| 257 | |||
| 258 | /** | ||
| 259 | * Adds an action listener to the <code>Timer</code>. | ||
| 260 | * | ||
| 261 | * @param listener the listener to add | ||
| 262 | * | ||
| 263 | * @see #Timer | ||
| 264 | */ | ||
| 265 | public void addActionListener(ActionListener listener) { | ||
| 266 | listenerList.add(ActionListener.class, listener); | ||
| 267 | } | ||
| 268 | |||
| 269 | |||
| 270 | /** | ||
| 271 | * Removes the specified action listener from the <code>Timer</code>. | ||
| 272 | * | ||
| 273 | * @param listener the listener to remove | ||
| 274 | */ | ||
| 275 | public void removeActionListener(ActionListener listener) { | ||
| 276 | listenerList.remove(ActionListener.class, listener); | ||
| 277 | } | ||
| 278 | |||
| 279 | |||
| 280 | /** | ||
| 281 | * Returns an array of all the action listeners registered | ||
| 282 | * on this timer. | ||
| 283 | * | ||
| 284 | * @return all of the timer's <code>ActionListener</code>s or an empty | ||
| 285 | * array if no action listeners are currently registered | ||
| 286 | * | ||
| 287 | * @see #addActionListener | ||
| 288 | * @see #removeActionListener | ||
| 289 | * | ||
| 290 | * @since 1.4 | ||
| 291 | */ | ||
| 292 | public ActionListener[] getActionListeners() { | ||
| 293 | return listenerList.getListeners(ActionListener.class); | ||
| 294 | } | ||
| 295 | |||
| 296 | |||
| 297 | /** | ||
| 298 | * Notifies all listeners that have registered interest for | ||
| 299 | * notification on this event type. | ||
| 300 | * | ||
| 301 | * @param e the action event to fire | ||
| 302 | * @see EventListenerList | ||
| 303 | */ | ||
| 304 | protected void fireActionPerformed(ActionEvent e) { | ||
| 305 | // Guaranteed to return a non-null array | ||
| 306 | Object[] listeners = listenerList.getListenerList(); | ||
| 307 | |||
| 308 | // Process the listeners last to first, notifying | ||
| 309 | // those that are interested in this event | ||
| 310 | for (int i=listeners.length-2; i>=0; i-=2) { | ||
| 311 | if (listeners[i]==ActionListener.class) { | ||
| 312 | ((ActionListener)listeners[i+1]).actionPerformed(e); | ||
| 313 | } | ||
| 314 | } | ||
| 315 | } | ||
| 316 | |||
| 317 | /** | ||
| 318 | * Returns an array of all the objects currently registered as | ||
| 319 | * <code><em>Foo</em>Listener</code>s | ||
| 320 | * upon this <code>Timer</code>. | ||
| 321 | * <code><em>Foo</em>Listener</code>s | ||
| 322 | * are registered using the <code>add<em>Foo</em>Listener</code> method. | ||
| 323 | * <p> | ||
| 324 | * You can specify the <code>listenerType</code> argument | ||
| 325 | * with a class literal, such as <code><em>Foo</em>Listener.class</code>. | ||
| 326 | * For example, you can query a <code>Timer</code> | ||
| 327 | * instance <code>t</code> | ||
| 328 | * for its action listeners | ||
| 329 | * with the following code: | ||
| 330 | * | ||
| 331 | * <pre>ActionListener[] als = (ActionListener[])(t.getListeners(ActionListener.class));</pre> | ||
| 332 | * | ||
| 333 | * If no such listeners exist, | ||
| 334 | * this method returns an empty array. | ||
| 335 | * | ||
| 336 | * @param listenerType the type of listeners requested; | ||
| 337 | * this parameter should specify an interface | ||
| 338 | * that descends from <code>java.util.EventListener</code> | ||
| 339 | * @return an array of all objects registered as | ||
| 340 | * <code><em>Foo</em>Listener</code>s | ||
| 341 | * on this timer, | ||
| 342 | * or an empty array if no such | ||
| 343 | * listeners have been added | ||
| 344 | * @exception ClassCastException if <code>listenerType</code> doesn't | ||
| 345 | * specify a class or interface that implements | ||
| 346 | * <code>java.util.EventListener</code> | ||
| 347 | * | ||
| 348 | * @see #getActionListeners | ||
| 349 | * @see #addActionListener | ||
| 350 | * @see #removeActionListener | ||
| 351 | * | ||
| 352 | * @since 1.3 | ||
| 353 | */ | ||
| 354 | public <T extends EventListener> T[] getListeners(Class<T> listenerType) { | ||
| 355 | return listenerList.getListeners(listenerType); | ||
| 356 | } | ||
| 357 | |||
| 358 | /** | ||
| 359 | * Returns the timer queue. | ||
| 360 | */ | ||
| 361 | private TimerQueue timerQueue() { | ||
| 362 | return TimerQueue.sharedInstance(); | ||
| 363 | } | ||
| 364 | |||
| 365 | |||
| 366 | /** | ||
| 367 | * Enables or disables the timer log. When enabled, a message | ||
| 368 | * is posted to <code>System.out</code> whenever the timer goes off. | ||
| 369 | * | ||
| 370 | * @param flag <code>true</code> to enable logging | ||
| 371 | * @see #getLogTimers | ||
| 372 | */ | ||
| 373 | public static void setLogTimers(boolean flag) { | ||
| 374 | logTimers = flag; | ||
| 375 | } | ||
| 376 | |||
| 377 | |||
| 378 | /** | ||
| 379 | * Returns <code>true</code> if logging is enabled. | ||
| 380 | * | ||
| 381 | * @return <code>true</code> if logging is enabled; otherwise, false | ||
| 382 | * @see #setLogTimers | ||
| 383 | */ | ||
| 384 | public static boolean getLogTimers() { | ||
| 385 | return logTimers; | ||
| 386 | } | ||
| 387 | |||
| 388 | |||
| 389 | /** | ||
| 390 | * Sets the <code>Timer</code>'s between-event delay, the number of milliseconds | ||
| 391 | * between successive action events. This does not affect the initial delay | ||
| 392 | * property, which can be set by the {@code setInitialDelay} method. | ||
| 393 | * | ||
| 394 | * @param delay the delay in milliseconds | ||
| 395 | * @see #setInitialDelay | ||
| 396 | */ | ||
| 397 | public void setDelay(int delay) { | ||
| 398 | if (delay < 0) { | ||
| 399 | throw new IllegalArgumentException("Invalid delay: " + delay); | ||
| 400 | } | ||
| 401 | else { | ||
| 402 | this.delay = delay; | ||
| 403 | } | ||
| 404 | } | ||
| 405 | |||
| 406 | |||
| 407 | /** | ||
| 408 | * Returns the delay, in milliseconds, | ||
| 409 | * between firings of action events. | ||
| 410 | * | ||
| 411 | * @see #setDelay | ||
| 412 | * @see #getInitialDelay | ||
| 413 | */ | ||
| 414 | public int getDelay() { | ||
| 415 | return delay; | ||
| 416 | } | ||
| 417 | |||
| 418 | |||
| 419 | /** | ||
| 420 | * Sets the <code>Timer</code>'s initial delay, the time | ||
| 421 | * in milliseconds to wait after the timer is started | ||
| 422 | * before firing the first event. Upon construction, this | ||
| 423 | * is set to be the same as the between-event delay, | ||
| 424 | * but then its value is independent and remains unaffected | ||
| 425 | * by changes to the between-event delay. | ||
| 426 | * | ||
| 427 | * @param initialDelay the initial delay, in milliseconds | ||
| 428 | * @see #setDelay | ||
| 429 | */ | ||
| 430 | public void setInitialDelay(int initialDelay) { | ||
| 431 | if (initialDelay < 0) { | ||
| 432 | throw new IllegalArgumentException("Invalid initial delay: " + | ||
| 433 | initialDelay); | ||
| 434 | } | ||
| 435 | else { | ||
| 436 | this.initialDelay = initialDelay; | ||
| 437 | } | ||
| 438 | } | ||
| 439 | |||
| 440 | |||
| 441 | /** | ||
| 442 | * Returns the <code>Timer</code>'s initial delay. | ||
| 443 | * | ||
| 444 | * @see #setInitialDelay | ||
| 445 | * @see #setDelay | ||
| 446 | */ | ||
| 447 | public int getInitialDelay() { | ||
| 448 | return initialDelay; | ||
| 449 | } | ||
| 450 | |||
| 451 | |||
| 452 | /** | ||
| 453 | * If <code>flag</code> is <code>false</code>, | ||
| 454 | * instructs the <code>Timer</code> to send only one | ||
| 455 | * action event to its listeners. | ||
| 456 | * | ||
| 457 | * @param flag specify <code>false</code> to make the timer | ||
| 458 | * stop after sending its first action event | ||
| 459 | */ | ||
| 460 | public void setRepeats(boolean flag) { | ||
| 461 | repeats = flag; | ||
| 462 | } | ||
| 463 | |||
| 464 | |||
| 465 | /** | ||
| 466 | * Returns <code>true</code> (the default) | ||
| 467 | * if the <code>Timer</code> will send | ||
| 468 | * an action event | ||
| 469 | * to its listeners multiple times. | ||
| 470 | * | ||
| 471 | * @see #setRepeats | ||
| 472 | */ | ||
| 473 | public boolean isRepeats() { | ||
| 474 | return repeats; | ||
| 475 | } | ||
| 476 | |||
| 477 | |||
| 478 | /** | ||
| 479 | * Sets whether the <code>Timer</code> coalesces multiple pending | ||
| 480 | * <code>ActionEvent</code> firings. | ||
| 481 | * A busy application may not be able | ||
| 482 | * to keep up with a <code>Timer</code>'s event generation, | ||
| 483 | * causing multiple | ||
| 484 | * action events to be queued. When processed, | ||
| 485 | * the application sends these events one after the other, causing the | ||
| 486 | * <code>Timer</code>'s listeners to receive a sequence of | ||
| 487 | * events with no delay between them. Coalescing avoids this situation | ||
| 488 | * by reducing multiple pending events to a single event. | ||
| 489 | * <code>Timer</code>s | ||
| 490 | * coalesce events by default. | ||
| 491 | * | ||
| 492 | * @param flag specify <code>false</code> to turn off coalescing | ||
| 493 | */ | ||
| 494 | public void setCoalesce(boolean flag) { | ||
| 495 | boolean old = coalesce; | ||
| 496 | coalesce = flag; | ||
| 497 | if (!old && coalesce) { | ||
| 498 | // We must do this as otherwise if the Timer once notified | ||
| 499 | // in !coalese mode notify will be stuck to true and never | ||
| 500 | // become false. | ||
| 501 | cancelEvent(); | ||
| 502 | } | ||
| 503 | } | ||
| 504 | |||
| 505 | |||
| 506 | /** | ||
| 507 | * Returns <code>true</code> if the <code>Timer</code> coalesces | ||
| 508 | * multiple pending action events. | ||
| 509 | * | ||
| 510 | * @see #setCoalesce | ||
| 511 | */ | ||
| 512 | public boolean isCoalesce() { | ||
| 513 | return coalesce; | ||
| 514 | } | ||
| 515 | |||
| 516 | |||
| 517 | /** | ||
| 518 | * Sets the string that will be delivered as the action command | ||
| 519 | * in <code>ActionEvent</code>s fired by this timer. | ||
| 520 | * <code>null</code> is an acceptable value. | ||
| 521 | * | ||
| 522 | * @param command the action command | ||
| 523 | * @since 1.6 | ||
| 524 | */ | ||
| 525 | public void setActionCommand(String command) { | ||
| 526 | this.actionCommand = command; | ||
| 527 | } | ||
| 528 | |||
| 529 | |||
| 530 | /** | ||
| 531 | * Returns the string that will be delivered as the action command | ||
| 532 | * in <code>ActionEvent</code>s fired by this timer. May be | ||
| 533 | * <code>null</code>, which is also the default. | ||
| 534 | * | ||
| 535 | * @return the action command used in firing events | ||
| 536 | * @since 1.6 | ||
| 537 | */ | ||
| 538 | public String getActionCommand() { | ||
| 539 | return actionCommand; | ||
| 540 | } | ||
| 541 | |||
| 542 | |||
| 543 | /** | ||
| 544 | * Starts the <code>Timer</code>, | ||
| 545 | * causing it to start sending action events | ||
| 546 | * to its listeners. | ||
| 547 | * | ||
| 548 | * @see #stop | ||
| 549 | */ | ||
| 550 | public void start() { | ||
| 551 | timerQueue().addTimer(this, getInitialDelay()); | ||
| 552 | } | ||
| 553 | |||
| 554 | |||
| 555 | /** | ||
| 556 | * Returns <code>true</code> if the <code>Timer</code> is running. | ||
| 557 | * | ||
| 558 | * @see #start | ||
| 559 | */ | ||
| 560 | public boolean isRunning() { | ||
| 561 | return timerQueue().containsTimer(this); | ||
| 562 | } | ||
| 563 | |||
| 564 | |||
| 565 | /** | ||
| 566 | * Stops the <code>Timer</code>, | ||
| 567 | * causing it to stop sending action events | ||
| 568 | * to its listeners. | ||
| 569 | * | ||
| 570 | * @see #start | ||
| 571 | */ | ||
| 572 | public void stop() { | ||
| 573 | getLock().lock(); | ||
| 574 | try { | ||
| 575 | cancelEvent(); | ||
| 576 | timerQueue().removeTimer(this); | ||
| 577 | } finally { | ||
| 578 | getLock().unlock(); | ||
| 579 | } | ||
| 580 | } | ||
| 581 | |||
| 582 | |||
| 583 | /** | ||
| 584 | * Restarts the <code>Timer</code>, | ||
| 585 | * canceling any pending firings and causing | ||
| 586 | * it to fire with its initial delay. | ||
| 587 | */ | ||
| 588 | public void restart() { | ||
| 589 | getLock().lock(); | ||
| 590 | try { | ||
| 591 | stop(); | ||
| 592 | start(); | ||
| 593 | } finally { | ||
| 594 | getLock().unlock(); | ||
| 595 | } | ||
| 596 | } | ||
| 597 | |||
| 598 | |||
| 599 | /** | ||
| 600 | * Resets the internal state to indicate this Timer shouldn't notify | ||
| 601 | * any of its listeners. This does not stop a repeatable Timer from | ||
| 602 | * firing again, use <code>stop</code> for that. | ||
| 603 | */ | ||
| 604 | void cancelEvent() { | ||
| 605 | notify.set(false); | ||
| 606 | } | ||
| 607 | |||
| 608 | |||
| 609 | void post() { | ||
| 610 | if (notify.compareAndSet(false, true) || !coalesce) { | ||
| 611 | AccessController.doPrivileged(new PrivilegedAction<Void>() { | ||
| 612 | public Void run() { | ||
| 613 | SwingUtilities.invokeLater(doPostEvent); | ||
| 614 | return null; | ||
| 615 | } | ||
| 616 | }, getAccessControlContext()); | ||
| 617 | } | ||
| 618 | } | ||
| 619 | |||
| 620 | Lock getLock() { | ||
| 621 | return lock; | ||
| 622 | } | ||
| 623 | |||
| 624 | private void readObject(ObjectInputStream in) | ||
| 625 | throws ClassNotFoundException, IOException | ||
| 626 | { | ||
| 627 | this.acc = AccessController.getContext(); | ||
| 628 | in.defaultReadObject(); | ||
| 629 | } | ||
| 630 | |||
| 631 | /* | ||
| 632 | * We have to use readResolve because we can not initialize final | ||
| 633 | * fields for deserialized object otherwise | ||
| 634 | */ | ||
| 635 | private Object readResolve() { | ||
| 636 | Timer timer = new Timer(getDelay(), null); | ||
| 637 | timer.listenerList = listenerList; | ||
| 638 | timer.initialDelay = initialDelay; | ||
| 639 | timer.delay = delay; | ||
| 640 | timer.repeats = repeats; | ||
| 641 | timer.coalesce = coalesce; | ||
| 642 | timer.actionCommand = actionCommand; | ||
| 643 | return timer; | ||
| 644 | } | ||
| 645 | } | ||