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| 1 | /* | ||
| 2 | * Copyright (c) 2005, 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 | package javax.swing; | ||
| 26 | |||
| 27 | import java.lang.ref.WeakReference; | ||
| 28 | import java.security.AccessController; | ||
| 29 | import java.security.PrivilegedAction; | ||
| 30 | import java.beans.PropertyChangeListener; | ||
| 31 | import java.beans.PropertyChangeSupport; | ||
| 32 | import java.beans.PropertyChangeEvent; | ||
| 33 | import java.util.List; | ||
| 34 | import java.util.concurrent.*; | ||
| 35 | import java.util.concurrent.locks.*; | ||
| 36 | |||
| 37 | import java.awt.event.*; | ||
| 38 | |||
| 39 | import javax.swing.SwingUtilities; | ||
| 40 | |||
| 41 | import sun.awt.AppContext; | ||
| 42 | import sun.swing.AccumulativeRunnable; | ||
| 43 | |||
| 44 | /** | ||
| 45 | * An abstract class to perform lengthy GUI-interaction tasks in a | ||
| 46 | * background thread. Several background threads can be used to execute such | ||
| 47 | * tasks. However, the exact strategy of choosing a thread for any particular | ||
| 48 | * {@code SwingWorker} is unspecified and should not be relied on. | ||
| 49 | * <p> | ||
| 50 | * When writing a multi-threaded application using Swing, there are | ||
| 51 | * two constraints to keep in mind: | ||
| 52 | * (refer to | ||
| 53 | * <a href="http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html"> | ||
| 54 | * How to Use Threads | ||
| 55 | * </a> for more details): | ||
| 56 | * <ul> | ||
| 57 | * <li> Time-consuming tasks should not be run on the <i>Event | ||
| 58 | * Dispatch Thread</i>. Otherwise the application becomes unresponsive. | ||
| 59 | * </li> | ||
| 60 | * <li> Swing components should be accessed on the <i>Event | ||
| 61 | * Dispatch Thread</i> only. | ||
| 62 | * </li> | ||
| 63 | * </ul> | ||
| 64 | * | ||
| 65 | * <p> | ||
| 66 | * | ||
| 67 | * <p> | ||
| 68 | * These constraints mean that a GUI application with time intensive | ||
| 69 | * computing needs at least two threads: 1) a thread to perform the lengthy | ||
| 70 | * task and 2) the <i>Event Dispatch Thread</i> (EDT) for all GUI-related | ||
| 71 | * activities. This involves inter-thread communication which can be | ||
| 72 | * tricky to implement. | ||
| 73 | * | ||
| 74 | * <p> | ||
| 75 | * {@code SwingWorker} is designed for situations where you need to have a long | ||
| 76 | * running task run in a background thread and provide updates to the UI | ||
| 77 | * either when done, or while processing. | ||
| 78 | * Subclasses of {@code SwingWorker} must implement | ||
| 79 | * the {@link #doInBackground} method to perform the background computation. | ||
| 80 | * | ||
| 81 | * | ||
| 82 | * <p> | ||
| 83 | * <b>Workflow</b> | ||
| 84 | * <p> | ||
| 85 | * There are three threads involved in the life cycle of a | ||
| 86 | * {@code SwingWorker} : | ||
| 87 | * <ul> | ||
| 88 | * <li> | ||
| 89 | * <p> | ||
| 90 | * <i>Current</i> thread: The {@link #execute} method is | ||
| 91 | * called on this thread. It schedules {@code SwingWorker} for the execution on a | ||
| 92 | * <i>worker</i> | ||
| 93 | * thread and returns immediately. One can wait for the {@code SwingWorker} to | ||
| 94 | * complete using the {@link #get get} methods. | ||
| 95 | * <li> | ||
| 96 | * <p> | ||
| 97 | * <i>Worker</i> thread: The {@link #doInBackground} | ||
| 98 | * method is called on this thread. | ||
| 99 | * This is where all background activities should happen. To notify | ||
| 100 | * {@code PropertyChangeListeners} about bound properties changes use the | ||
| 101 | * {@link #firePropertyChange firePropertyChange} and | ||
| 102 | * {@link #getPropertyChangeSupport} methods. By default there are two bound | ||
| 103 | * properties available: {@code state} and {@code progress}. | ||
| 104 | * <li> | ||
| 105 | * <p> | ||
| 106 | * <i>Event Dispatch Thread</i>: All Swing related activities occur | ||
| 107 | * on this thread. {@code SwingWorker} invokes the | ||
| 108 | * {@link #process process} and {@link #done} methods and notifies | ||
| 109 | * any {@code PropertyChangeListeners} on this thread. | ||
| 110 | * </ul> | ||
| 111 | * | ||
| 112 | * <p> | ||
| 113 | * Often, the <i>Current</i> thread is the <i>Event Dispatch | ||
| 114 | * Thread</i>. | ||
| 115 | * | ||
| 116 | * | ||
| 117 | * <p> | ||
| 118 | * Before the {@code doInBackground} method is invoked on a <i>worker</i> thread, | ||
| 119 | * {@code SwingWorker} notifies any {@code PropertyChangeListeners} about the | ||
| 120 | * {@code state} property change to {@code StateValue.STARTED}. After the | ||
| 121 | * {@code doInBackground} method is finished the {@code done} method is | ||
| 122 | * executed. Then {@code SwingWorker} notifies any {@code PropertyChangeListeners} | ||
| 123 | * about the {@code state} property change to {@code StateValue.DONE}. | ||
| 124 | * | ||
| 125 | * <p> | ||
| 126 | * {@code SwingWorker} is only designed to be executed once. Executing a | ||
| 127 | * {@code SwingWorker} more than once will not result in invoking the | ||
| 128 | * {@code doInBackground} method twice. | ||
| 129 | * | ||
| 130 | * <p> | ||
| 131 | * <b>Sample Usage</b> | ||
| 132 | * <p> | ||
| 133 | * The following example illustrates the simplest use case. Some | ||
| 134 | * processing is done in the background and when done you update a Swing | ||
| 135 | * component. | ||
| 136 | * | ||
| 137 | * <p> | ||
| 138 | * Say we want to find the "Meaning of Life" and display the result in | ||
| 139 | * a {@code JLabel}. | ||
| 140 | * | ||
| 141 | * <pre> | ||
| 142 | * final JLabel label; | ||
| 143 | * class MeaningOfLifeFinder extends SwingWorker<String, Object> { | ||
| 144 | * {@code @Override} | ||
| 145 | * public String doInBackground() { | ||
| 146 | * return findTheMeaningOfLife(); | ||
| 147 | * } | ||
| 148 | * | ||
| 149 | * {@code @Override} | ||
| 150 | * protected void done() { | ||
| 151 | * try { | ||
| 152 | * label.setText(get()); | ||
| 153 | * } catch (Exception ignore) { | ||
| 154 | * } | ||
| 155 | * } | ||
| 156 | * } | ||
| 157 | * | ||
| 158 | * (new MeaningOfLifeFinder()).execute(); | ||
| 159 | * </pre> | ||
| 160 | * | ||
| 161 | * <p> | ||
| 162 | * The next example is useful in situations where you wish to process data | ||
| 163 | * as it is ready on the <i>Event Dispatch Thread</i>. | ||
| 164 | * | ||
| 165 | * <p> | ||
| 166 | * Now we want to find the first N prime numbers and display the results in a | ||
| 167 | * {@code JTextArea}. While this is computing, we want to update our | ||
| 168 | * progress in a {@code JProgressBar}. Finally, we also want to print | ||
| 169 | * the prime numbers to {@code System.out}. | ||
| 170 | * <pre> | ||
| 171 | * class PrimeNumbersTask extends | ||
| 172 | * SwingWorker<List<Integer>, Integer> { | ||
| 173 | * PrimeNumbersTask(JTextArea textArea, int numbersToFind) { | ||
| 174 | * //initialize | ||
| 175 | * } | ||
| 176 | * | ||
| 177 | * {@code @Override} | ||
| 178 | * public List<Integer> doInBackground() { | ||
| 179 | * while (! enough && ! isCancelled()) { | ||
| 180 | * number = nextPrimeNumber(); | ||
| 181 | * publish(number); | ||
| 182 | * setProgress(100 * numbers.size() / numbersToFind); | ||
| 183 | * } | ||
| 184 | * } | ||
| 185 | * return numbers; | ||
| 186 | * } | ||
| 187 | * | ||
| 188 | * {@code @Override} | ||
| 189 | * protected void process(List<Integer> chunks) { | ||
| 190 | * for (int number : chunks) { | ||
| 191 | * textArea.append(number + "\n"); | ||
| 192 | * } | ||
| 193 | * } | ||
| 194 | * } | ||
| 195 | * | ||
| 196 | * JTextArea textArea = new JTextArea(); | ||
| 197 | * final JProgressBar progressBar = new JProgressBar(0, 100); | ||
| 198 | * PrimeNumbersTask task = new PrimeNumbersTask(textArea, N); | ||
| 199 | * task.addPropertyChangeListener( | ||
| 200 | * new PropertyChangeListener() { | ||
| 201 | * public void propertyChange(PropertyChangeEvent evt) { | ||
| 202 | * if ("progress".equals(evt.getPropertyName())) { | ||
| 203 | * progressBar.setValue((Integer)evt.getNewValue()); | ||
| 204 | * } | ||
| 205 | * } | ||
| 206 | * }); | ||
| 207 | * | ||
| 208 | * task.execute(); | ||
| 209 | * System.out.println(task.get()); //prints all prime numbers we have got | ||
| 210 | * </pre> | ||
| 211 | * | ||
| 212 | * <p> | ||
| 213 | * Because {@code SwingWorker} implements {@code Runnable}, a | ||
| 214 | * {@code SwingWorker} can be submitted to an | ||
| 215 | * {@link java.util.concurrent.Executor} for execution. | ||
| 216 | * | ||
| 217 | * @author Igor Kushnirskiy | ||
| 218 | * | ||
| 219 | * @param <T> the result type returned by this {@code SwingWorker's} | ||
| 220 | * {@code doInBackground} and {@code get} methods | ||
| 221 | * @param <V> the type used for carrying out intermediate results by this | ||
| 222 | * {@code SwingWorker's} {@code publish} and {@code process} methods | ||
| 223 | * | ||
| 224 | * @since 1.6 | ||
| 225 | */ | ||
| 226 | public abstract class SwingWorker<T, V> implements RunnableFuture<T> { | ||
| 227 | /** | ||
| 228 | * number of worker threads. | ||
| 229 | */ | ||
| 230 | private static final int MAX_WORKER_THREADS = 10; | ||
| 231 | |||
| 232 | /** | ||
| 233 | * current progress. | ||
| 234 | */ | ||
| 235 | private volatile int progress; | ||
| 236 | |||
| 237 | /** | ||
| 238 | * current state. | ||
| 239 | */ | ||
| 240 | private volatile StateValue state; | ||
| 241 | |||
| 242 | /** | ||
| 243 | * everything is run inside this FutureTask. Also it is used as | ||
| 244 | * a delegatee for the Future API. | ||
| 245 | */ | ||
| 246 | private final FutureTask<T> future; | ||
| 247 | |||
| 248 | /** | ||
| 249 | * all propertyChangeSupport goes through this. | ||
| 250 | */ | ||
| 251 | private final PropertyChangeSupport propertyChangeSupport; | ||
| 252 | |||
| 253 | /** | ||
| 254 | * handler for {@code process} mehtod. | ||
| 255 | */ | ||
| 256 | private AccumulativeRunnable<V> doProcess; | ||
| 257 | |||
| 258 | /** | ||
| 259 | * handler for progress property change notifications. | ||
| 260 | */ | ||
| 261 | private AccumulativeRunnable<Integer> doNotifyProgressChange; | ||
| 262 | |||
| 263 | private final AccumulativeRunnable<Runnable> doSubmit = getDoSubmit(); | ||
| 264 | |||
| 265 | /** | ||
| 266 | * Values for the {@code state} bound property. | ||
| 267 | * @since 1.6 | ||
| 268 | */ | ||
| 269 | public enum StateValue { | ||
| 270 | /** | ||
| 271 | * Initial {@code SwingWorker} state. | ||
| 272 | */ | ||
| 273 | PENDING, | ||
| 274 | /** | ||
| 275 | * {@code SwingWorker} is {@code STARTED} | ||
| 276 | * before invoking {@code doInBackground}. | ||
| 277 | */ | ||
| 278 | STARTED, | ||
| 279 | |||
| 280 | /** | ||
| 281 | * {@code SwingWorker} is {@code DONE} | ||
| 282 | * after {@code doInBackground} method | ||
| 283 | * is finished. | ||
| 284 | */ | ||
| 285 | DONE | ||
| 286 | } | ||
| 287 | |||
| 288 | /** | ||
| 289 | * Constructs this {@code SwingWorker}. | ||
| 290 | */ | ||
| 291 | public SwingWorker() { | ||
| 292 | Callable<T> callable = | ||
| 293 | new Callable<T>() { | ||
| 294 | public T call() throws Exception { | ||
| 295 | setState(StateValue.STARTED); | ||
| 296 | return doInBackground(); | ||
| 297 | } | ||
| 298 | }; | ||
| 299 | |||
| 300 | future = new FutureTask<T>(callable) { | ||
| 301 | @Override | ||
| 302 | protected void done() { | ||
| 303 | doneEDT(); | ||
| 304 | setState(StateValue.DONE); | ||
| 305 | } | ||
| 306 | }; | ||
| 307 | |||
| 308 | state = StateValue.PENDING; | ||
| 309 | propertyChangeSupport = new SwingWorkerPropertyChangeSupport(this); | ||
| 310 | doProcess = null; | ||
| 311 | doNotifyProgressChange = null; | ||
| 312 | } | ||
| 313 | |||
| 314 | /** | ||
| 315 | * Computes a result, or throws an exception if unable to do so. | ||
| 316 | * | ||
| 317 | * <p> | ||
| 318 | * Note that this method is executed only once. | ||
| 319 | * | ||
| 320 | * <p> | ||
| 321 | * Note: this method is executed in a background thread. | ||
| 322 | * | ||
| 323 | * | ||
| 324 | * @return the computed result | ||
| 325 | * @throws Exception if unable to compute a result | ||
| 326 | * | ||
| 327 | */ | ||
| 328 | protected abstract T doInBackground() throws Exception ; | ||
| 329 | |||
| 330 | /** | ||
| 331 | * Sets this {@code Future} to the result of computation unless | ||
| 332 | * it has been cancelled. | ||
| 333 | */ | ||
| 334 | public final void run() { | ||
| 335 | future.run(); | ||
| 336 | } | ||
| 337 | |||
| 338 | /** | ||
| 339 | * Sends data chunks to the {@link #process} method. This method is to be | ||
| 340 | * used from inside the {@code doInBackground} method to deliver | ||
| 341 | * intermediate results | ||
| 342 | * for processing on the <i>Event Dispatch Thread</i> inside the | ||
| 343 | * {@code process} method. | ||
| 344 | * | ||
| 345 | * <p> | ||
| 346 | * Because the {@code process} method is invoked asynchronously on | ||
| 347 | * the <i>Event Dispatch Thread</i> | ||
| 348 | * multiple invocations to the {@code publish} method | ||
| 349 | * might occur before the {@code process} method is executed. For | ||
| 350 | * performance purposes all these invocations are coalesced into one | ||
| 351 | * invocation with concatenated arguments. | ||
| 352 | * | ||
| 353 | * <p> | ||
| 354 | * For example: | ||
| 355 | * | ||
| 356 | * <pre> | ||
| 357 | * publish("1"); | ||
| 358 | * publish("2", "3"); | ||
| 359 | * publish("4", "5", "6"); | ||
| 360 | * </pre> | ||
| 361 | * | ||
| 362 | * might result in: | ||
| 363 | * | ||
| 364 | * <pre> | ||
| 365 | * process("1", "2", "3", "4", "5", "6") | ||
| 366 | * </pre> | ||
| 367 | * | ||
| 368 | * <p> | ||
| 369 | * <b>Sample Usage</b>. This code snippet loads some tabular data and | ||
| 370 | * updates {@code DefaultTableModel} with it. Note that it safe to mutate | ||
| 371 | * the tableModel from inside the {@code process} method because it is | ||
| 372 | * invoked on the <i>Event Dispatch Thread</i>. | ||
| 373 | * | ||
| 374 | * <pre> | ||
| 375 | * class TableSwingWorker extends | ||
| 376 | * SwingWorker<DefaultTableModel, Object[]> { | ||
| 377 | * private final DefaultTableModel tableModel; | ||
| 378 | * | ||
| 379 | * public TableSwingWorker(DefaultTableModel tableModel) { | ||
| 380 | * this.tableModel = tableModel; | ||
| 381 | * } | ||
| 382 | * | ||
| 383 | * {@code @Override} | ||
| 384 | * protected DefaultTableModel doInBackground() throws Exception { | ||
| 385 | * for (Object[] row = loadData(); | ||
| 386 | * ! isCancelled() && row != null; | ||
| 387 | * row = loadData()) { | ||
| 388 | * publish((Object[]) row); | ||
| 389 | * } | ||
| 390 | * return tableModel; | ||
| 391 | * } | ||
| 392 | * | ||
| 393 | * {@code @Override} | ||
| 394 | * protected void process(List<Object[]> chunks) { | ||
| 395 | * for (Object[] row : chunks) { | ||
| 396 | * tableModel.addRow(row); | ||
| 397 | * } | ||
| 398 | * } | ||
| 399 | * } | ||
| 400 | * </pre> | ||
| 401 | * | ||
| 402 | * @param chunks intermediate results to process | ||
| 403 | * | ||
| 404 | * @see #process | ||
| 405 | * | ||
| 406 | */ | ||
| 407 | @SafeVarargs | ||
| 408 | protected final void publish(V... chunks) { | ||
| 409 | synchronized (this) { | ||
| 410 | if (doProcess == null) { | ||
| 411 | doProcess = new AccumulativeRunnable<V>() { | ||
| 412 | @Override | ||
| 413 | public void run(List<V> args) { | ||
| 414 | process(args); | ||
| 415 | } | ||
| 416 | @Override | ||
| 417 | protected void submit() { | ||
| 418 | doSubmit.add(this); | ||
| 419 | } | ||
| 420 | }; | ||
| 421 | } | ||
| 422 | } | ||
| 423 | doProcess.add(chunks); | ||
| 424 | } | ||
| 425 | |||
| 426 | /** | ||
| 427 | * Receives data chunks from the {@code publish} method asynchronously on the | ||
| 428 | * <i>Event Dispatch Thread</i>. | ||
| 429 | * | ||
| 430 | * <p> | ||
| 431 | * Please refer to the {@link #publish} method for more details. | ||
| 432 | * | ||
| 433 | * @param chunks intermediate results to process | ||
| 434 | * | ||
| 435 | * @see #publish | ||
| 436 | * | ||
| 437 | */ | ||
| 438 | protected void process(List<V> chunks) { | ||
| 439 | } | ||
| 440 | |||
| 441 | /** | ||
| 442 | * Executed on the <i>Event Dispatch Thread</i> after the {@code doInBackground} | ||
| 443 | * method is finished. The default | ||
| 444 | * implementation does nothing. Subclasses may override this method to | ||
| 445 | * perform completion actions on the <i>Event Dispatch Thread</i>. Note | ||
| 446 | * that you can query status inside the implementation of this method to | ||
| 447 | * determine the result of this task or whether this task has been cancelled. | ||
| 448 | * | ||
| 449 | * @see #doInBackground | ||
| 450 | * @see #isCancelled() | ||
| 451 | * @see #get | ||
| 452 | */ | ||
| 453 | protected void done() { | ||
| 454 | } | ||
| 455 | |||
| 456 | /** | ||
| 457 | * Sets the {@code progress} bound property. | ||
| 458 | * The value should be from 0 to 100. | ||
| 459 | * | ||
| 460 | * <p> | ||
| 461 | * Because {@code PropertyChangeListener}s are notified asynchronously on | ||
| 462 | * the <i>Event Dispatch Thread</i> multiple invocations to the | ||
| 463 | * {@code setProgress} method might occur before any | ||
| 464 | * {@code PropertyChangeListeners} are invoked. For performance purposes | ||
| 465 | * all these invocations are coalesced into one invocation with the last | ||
| 466 | * invocation argument only. | ||
| 467 | * | ||
| 468 | * <p> | ||
| 469 | * For example, the following invokations: | ||
| 470 | * | ||
| 471 | * <pre> | ||
| 472 | * setProgress(1); | ||
| 473 | * setProgress(2); | ||
| 474 | * setProgress(3); | ||
| 475 | * </pre> | ||
| 476 | * | ||
| 477 | * might result in a single {@code PropertyChangeListener} notification with | ||
| 478 | * the value {@code 3}. | ||
| 479 | * | ||
| 480 | * @param progress the progress value to set | ||
| 481 | * @throws IllegalArgumentException is value not from 0 to 100 | ||
| 482 | */ | ||
| 483 | protected final void setProgress(int progress) { | ||
| 484 | if (progress < 0 || progress > 100) { | ||
| 485 | throw new IllegalArgumentException("the value should be from 0 to 100"); | ||
| 486 | } | ||
| 487 | if (this.progress == progress) { | ||
| 488 | return; | ||
| 489 | } | ||
| 490 | int oldProgress = this.progress; | ||
| 491 | this.progress = progress; | ||
| 492 | if (! getPropertyChangeSupport().hasListeners("progress")) { | ||
| 493 | return; | ||
| 494 | } | ||
| 495 | synchronized (this) { | ||
| 496 | if (doNotifyProgressChange == null) { | ||
| 497 | doNotifyProgressChange = | ||
| 498 | new AccumulativeRunnable<Integer>() { | ||
| 499 | @Override | ||
| 500 | public void run(List<Integer> args) { | ||
| 501 | firePropertyChange("progress", | ||
| 502 | args.get(0), | ||
| 503 | args.get(args.size() - 1)); | ||
| 504 | } | ||
| 505 | @Override | ||
| 506 | protected void submit() { | ||
| 507 | doSubmit.add(this); | ||
| 508 | } | ||
| 509 | }; | ||
| 510 | } | ||
| 511 | } | ||
| 512 | doNotifyProgressChange.add(oldProgress, progress); | ||
| 513 | } | ||
| 514 | |||
| 515 | /** | ||
| 516 | * Returns the {@code progress} bound property. | ||
| 517 | * | ||
| 518 | * @return the progress bound property. | ||
| 519 | */ | ||
| 520 | public final int getProgress() { | ||
| 521 | return progress; | ||
| 522 | } | ||
| 523 | |||
| 524 | /** | ||
| 525 | * Schedules this {@code SwingWorker} for execution on a <i>worker</i> | ||
| 526 | * thread. There are a number of <i>worker</i> threads available. In the | ||
| 527 | * event all <i>worker</i> threads are busy handling other | ||
| 528 | * {@code SwingWorkers} this {@code SwingWorker} is placed in a waiting | ||
| 529 | * queue. | ||
| 530 | * | ||
| 531 | * <p> | ||
| 532 | * Note: | ||
| 533 | * {@code SwingWorker} is only designed to be executed once. Executing a | ||
| 534 | * {@code SwingWorker} more than once will not result in invoking the | ||
| 535 | * {@code doInBackground} method twice. | ||
| 536 | */ | ||
| 537 | public final void execute() { | ||
| 538 | getWorkersExecutorService().execute(this); | ||
| 539 | } | ||
| 540 | |||
| 541 | // Future methods START | ||
| 542 | /** | ||
| 543 | * {@inheritDoc} | ||
| 544 | */ | ||
| 545 | public final boolean cancel(boolean mayInterruptIfRunning) { | ||
| 546 | return future.cancel(mayInterruptIfRunning); | ||
| 547 | } | ||
| 548 | |||
| 549 | /** | ||
| 550 | * {@inheritDoc} | ||
| 551 | */ | ||
| 552 | public final boolean isCancelled() { | ||
| 553 | return future.isCancelled(); | ||
| 554 | } | ||
| 555 | |||
| 556 | /** | ||
| 557 | * {@inheritDoc} | ||
| 558 | */ | ||
| 559 | public final boolean isDone() { | ||
| 560 | return future.isDone(); | ||
| 561 | } | ||
| 562 | |||
| 563 | /** | ||
| 564 | * {@inheritDoc} | ||
| 565 | * <p> | ||
| 566 | * Note: calling {@code get} on the <i>Event Dispatch Thread</i> blocks | ||
| 567 | * <i>all</i> events, including repaints, from being processed until this | ||
| 568 | * {@code SwingWorker} is complete. | ||
| 569 | * | ||
| 570 | * <p> | ||
| 571 | * When you want the {@code SwingWorker} to block on the <i>Event | ||
| 572 | * Dispatch Thread</i> we recommend that you use a <i>modal dialog</i>. | ||
| 573 | * | ||
| 574 | * <p> | ||
| 575 | * For example: | ||
| 576 | * | ||
| 577 | * <pre> | ||
| 578 | * class SwingWorkerCompletionWaiter extends PropertyChangeListener { | ||
| 579 | * private JDialog dialog; | ||
| 580 | * | ||
| 581 | * public SwingWorkerCompletionWaiter(JDialog dialog) { | ||
| 582 | * this.dialog = dialog; | ||
| 583 | * } | ||
| 584 | * | ||
| 585 | * public void propertyChange(PropertyChangeEvent event) { | ||
| 586 | * if ("state".equals(event.getPropertyName()) | ||
| 587 | * && SwingWorker.StateValue.DONE == event.getNewValue()) { | ||
| 588 | * dialog.setVisible(false); | ||
| 589 | * dialog.dispose(); | ||
| 590 | * } | ||
| 591 | * } | ||
| 592 | * } | ||
| 593 | * JDialog dialog = new JDialog(owner, true); | ||
| 594 | * swingWorker.addPropertyChangeListener( | ||
| 595 | * new SwingWorkerCompletionWaiter(dialog)); | ||
| 596 | * swingWorker.execute(); | ||
| 597 | * //the dialog will be visible until the SwingWorker is done | ||
| 598 | * dialog.setVisible(true); | ||
| 599 | * </pre> | ||
| 600 | */ | ||
| 601 | public final T get() throws InterruptedException, ExecutionException { | ||
| 602 | return future.get(); | ||
| 603 | } | ||
| 604 | |||
| 605 | /** | ||
| 606 | * {@inheritDoc} | ||
| 607 | * <p> | ||
| 608 | * Please refer to {@link #get} for more details. | ||
| 609 | */ | ||
| 610 | public final T get(long timeout, TimeUnit unit) throws InterruptedException, | ||
| 611 | ExecutionException, TimeoutException { | ||
| 612 | return future.get(timeout, unit); | ||
| 613 | } | ||
| 614 | |||
| 615 | // Future methods END | ||
| 616 | |||
| 617 | // PropertyChangeSupports methods START | ||
| 618 | /** | ||
| 619 | * Adds a {@code PropertyChangeListener} to the listener list. The listener | ||
| 620 | * is registered for all properties. The same listener object may be added | ||
| 621 | * more than once, and will be called as many times as it is added. If | ||
| 622 | * {@code listener} is {@code null}, no exception is thrown and no action is taken. | ||
| 623 | * | ||
| 624 | * <p> | ||
| 625 | * Note: This is merely a convenience wrapper. All work is delegated to | ||
| 626 | * {@code PropertyChangeSupport} from {@link #getPropertyChangeSupport}. | ||
| 627 | * | ||
| 628 | * @param listener the {@code PropertyChangeListener} to be added | ||
| 629 | */ | ||
| 630 | public final void addPropertyChangeListener(PropertyChangeListener listener) { | ||
| 631 | getPropertyChangeSupport().addPropertyChangeListener(listener); | ||
| 632 | } | ||
| 633 | |||
| 634 | /** | ||
| 635 | * Removes a {@code PropertyChangeListener} from the listener list. This | ||
| 636 | * removes a {@code PropertyChangeListener} that was registered for all | ||
| 637 | * properties. If {@code listener} was added more than once to the same | ||
| 638 | * event source, it will be notified one less time after being removed. If | ||
| 639 | * {@code listener} is {@code null}, or was never added, no exception is | ||
| 640 | * thrown and no action is taken. | ||
| 641 | * | ||
| 642 | * <p> | ||
| 643 | * Note: This is merely a convenience wrapper. All work is delegated to | ||
| 644 | * {@code PropertyChangeSupport} from {@link #getPropertyChangeSupport}. | ||
| 645 | * | ||
| 646 | * @param listener the {@code PropertyChangeListener} to be removed | ||
| 647 | */ | ||
| 648 | public final void removePropertyChangeListener(PropertyChangeListener listener) { | ||
| 649 | getPropertyChangeSupport().removePropertyChangeListener(listener); | ||
| 650 | } | ||
| 651 | |||
| 652 | /** | ||
| 653 | * Reports a bound property update to any registered listeners. No event is | ||
| 654 | * fired if {@code old} and {@code new} are equal and non-null. | ||
| 655 | * | ||
| 656 | * <p> | ||
| 657 | * This {@code SwingWorker} will be the source for | ||
| 658 | * any generated events. | ||
| 659 | * | ||
| 660 | * <p> | ||
| 661 | * When called off the <i>Event Dispatch Thread</i> | ||
| 662 | * {@code PropertyChangeListeners} are notified asynchronously on | ||
| 663 | * the <i>Event Dispatch Thread</i>. | ||
| 664 | * <p> | ||
| 665 | * Note: This is merely a convenience wrapper. All work is delegated to | ||
| 666 | * {@code PropertyChangeSupport} from {@link #getPropertyChangeSupport}. | ||
| 667 | * | ||
| 668 | * | ||
| 669 | * @param propertyName the programmatic name of the property that was | ||
| 670 | * changed | ||
| 671 | * @param oldValue the old value of the property | ||
| 672 | * @param newValue the new value of the property | ||
| 673 | */ | ||
| 674 | public final void firePropertyChange(String propertyName, Object oldValue, | ||
| 675 | Object newValue) { | ||
| 676 | getPropertyChangeSupport().firePropertyChange(propertyName, | ||
| 677 | oldValue, newValue); | ||
| 678 | } | ||
| 679 | |||
| 680 | /** | ||
| 681 | * Returns the {@code PropertyChangeSupport} for this {@code SwingWorker}. | ||
| 682 | * This method is used when flexible access to bound properties support is | ||
| 683 | * needed. | ||
| 684 | * <p> | ||
| 685 | * This {@code SwingWorker} will be the source for | ||
| 686 | * any generated events. | ||
| 687 | * | ||
| 688 | * <p> | ||
| 689 | * Note: The returned {@code PropertyChangeSupport} notifies any | ||
| 690 | * {@code PropertyChangeListener}s asynchronously on the <i>Event Dispatch | ||
| 691 | * Thread</i> in the event that {@code firePropertyChange} or | ||
| 692 | * {@code fireIndexedPropertyChange} are called off the <i>Event Dispatch | ||
| 693 | * Thread</i>. | ||
| 694 | * | ||
| 695 | * @return {@code PropertyChangeSupport} for this {@code SwingWorker} | ||
| 696 | */ | ||
| 697 | public final PropertyChangeSupport getPropertyChangeSupport() { | ||
| 698 | return propertyChangeSupport; | ||
| 699 | } | ||
| 700 | |||
| 701 | // PropertyChangeSupports methods END | ||
| 702 | |||
| 703 | /** | ||
| 704 | * Returns the {@code SwingWorker} state bound property. | ||
| 705 | * | ||
| 706 | * @return the current state | ||
| 707 | */ | ||
| 708 | public final StateValue getState() { | ||
| 709 | /* | ||
| 710 | * DONE is a speacial case | ||
| 711 | * to keep getState and isDone is sync | ||
| 712 | */ | ||
| 713 | if (isDone()) { | ||
| 714 | return StateValue.DONE; | ||
| 715 | } else { | ||
| 716 | return state; | ||
| 717 | } | ||
| 718 | } | ||
| 719 | |||
| 720 | /** | ||
| 721 | * Sets this {@code SwingWorker} state bound property. | ||
| 722 | * @param state the state to set | ||
| 723 | */ | ||
| 724 | private void setState(StateValue state) { | ||
| 725 | StateValue old = this.state; | ||
| 726 | this.state = state; | ||
| 727 | firePropertyChange("state", old, state); | ||
| 728 | } | ||
| 729 | |||
| 730 | /** | ||
| 731 | * Invokes {@code done} on the EDT. | ||
| 732 | */ | ||
| 733 | private void doneEDT() { | ||
| 734 | Runnable doDone = | ||
| 735 | new Runnable() { | ||
| 736 | public void run() { | ||
| 737 | done(); | ||
| 738 | } | ||
| 739 | }; | ||
| 740 | if (SwingUtilities.isEventDispatchThread()) { | ||
| 741 | doDone.run(); | ||
| 742 | } else { | ||
| 743 | doSubmit.add(doDone); | ||
| 744 | } | ||
| 745 | } | ||
| 746 | |||
| 747 | |||
| 748 | /** | ||
| 749 | * returns workersExecutorService. | ||
| 750 | * | ||
| 751 | * returns the service stored in the appContext or creates it if | ||
| 752 | * necessary. | ||
| 753 | * | ||
| 754 | * @return ExecutorService for the {@code SwingWorkers} | ||
| 755 | */ | ||
| 756 | private static synchronized ExecutorService getWorkersExecutorService() { | ||
| 757 | final AppContext appContext = AppContext.getAppContext(); | ||
| 758 | ExecutorService executorService = | ||
| 759 | (ExecutorService) appContext.get(SwingWorker.class); | ||
| 760 | if (executorService == null) { | ||
| 761 | //this creates daemon threads. | ||
| 762 | ThreadFactory threadFactory = | ||
| 763 | new ThreadFactory() { | ||
| 764 | final ThreadFactory defaultFactory = | ||
| 765 | Executors.defaultThreadFactory(); | ||
| 766 | public Thread newThread(final Runnable r) { | ||
| 767 | Thread thread = | ||
| 768 | defaultFactory.newThread(r); | ||
| 769 | thread.setName("SwingWorker-" | ||
| 770 | + thread.getName()); | ||
| 771 | thread.setDaemon(true); | ||
| 772 | return thread; | ||
| 773 | } | ||
| 774 | }; | ||
| 775 | |||
| 776 | executorService = | ||
| 777 | new ThreadPoolExecutor(MAX_WORKER_THREADS, MAX_WORKER_THREADS, | ||
| 778 | 10L, TimeUnit.MINUTES, | ||
| 779 | new LinkedBlockingQueue<Runnable>(), | ||
| 780 | threadFactory); | ||
| 781 | appContext.put(SwingWorker.class, executorService); | ||
| 782 | |||
| 783 | // Don't use ShutdownHook here as it's not enough. We should track | ||
| 784 | // AppContext disposal instead of JVM shutdown, see 6799345 for details | ||
| 785 | final ExecutorService es = executorService; | ||
| 786 | appContext.addPropertyChangeListener(AppContext.DISPOSED_PROPERTY_NAME, | ||
| 787 | new PropertyChangeListener() { | ||
| 788 | @Override | ||
| 789 | public void propertyChange(PropertyChangeEvent pce) { | ||
| 790 | boolean disposed = (Boolean)pce.getNewValue(); | ||
| 791 | if (disposed) { | ||
| 792 | final WeakReference<ExecutorService> executorServiceRef = | ||
| 793 | new WeakReference<ExecutorService>(es); | ||
| 794 | final ExecutorService executorService = | ||
| 795 | executorServiceRef.get(); | ||
| 796 | if (executorService != null) { | ||
| 797 | AccessController.doPrivileged( | ||
| 798 | new PrivilegedAction<Void>() { | ||
| 799 | public Void run() { | ||
| 800 | executorService.shutdown(); | ||
| 801 | return null; | ||
| 802 | } | ||
| 803 | } | ||
| 804 | ); | ||
| 805 | } | ||
| 806 | } | ||
| 807 | } | ||
| 808 | } | ||
| 809 | ); | ||
| 810 | } | ||
| 811 | return executorService; | ||
| 812 | } | ||
| 813 | |||
| 814 | private static final Object DO_SUBMIT_KEY = new StringBuilder("doSubmit"); | ||
| 815 | private static AccumulativeRunnable<Runnable> getDoSubmit() { | ||
| 816 | synchronized (DO_SUBMIT_KEY) { | ||
| 817 | final AppContext appContext = AppContext.getAppContext(); | ||
| 818 | Object doSubmit = appContext.get(DO_SUBMIT_KEY); | ||
| 819 | if (doSubmit == null) { | ||
| 820 | doSubmit = new DoSubmitAccumulativeRunnable(); | ||
| 821 | appContext.put(DO_SUBMIT_KEY, doSubmit); | ||
| 822 | } | ||
| 823 | return (AccumulativeRunnable<Runnable>) doSubmit; | ||
| 824 | } | ||
| 825 | } | ||
| 826 | private static class DoSubmitAccumulativeRunnable | ||
| 827 | extends AccumulativeRunnable<Runnable> implements ActionListener { | ||
| 828 | private final static int DELAY = 1000 / 30; | ||
| 829 | @Override | ||
| 830 | protected void run(List<Runnable> args) { | ||
| 831 | for (Runnable runnable : args) { | ||
| 832 | runnable.run(); | ||
| 833 | } | ||
| 834 | } | ||
| 835 | @Override | ||
| 836 | protected void submit() { | ||
| 837 | Timer timer = new Timer(DELAY, this); | ||
| 838 | timer.setRepeats(false); | ||
| 839 | timer.start(); | ||
| 840 | } | ||
| 841 | public void actionPerformed(ActionEvent event) { | ||
| 842 | run(); | ||
| 843 | } | ||
| 844 | } | ||
| 845 | |||
| 846 | private class SwingWorkerPropertyChangeSupport | ||
| 847 | extends PropertyChangeSupport { | ||
| 848 | SwingWorkerPropertyChangeSupport(Object source) { | ||
| 849 | super(source); | ||
| 850 | } | ||
| 851 | @Override | ||
| 852 | public void firePropertyChange(final PropertyChangeEvent evt) { | ||
| 853 | if (SwingUtilities.isEventDispatchThread()) { | ||
| 854 | super.firePropertyChange(evt); | ||
| 855 | } else { | ||
| 856 | doSubmit.add( | ||
| 857 | new Runnable() { | ||
| 858 | public void run() { | ||
| 859 | SwingWorkerPropertyChangeSupport.this | ||
| 860 | .firePropertyChange(evt); | ||
| 861 | } | ||
| 862 | }); | ||
| 863 | } | ||
| 864 | } | ||
| 865 | } | ||
| 866 | } | ||