TextToSpeechService.java revision c3edf2a01a2cf2123a3de17ec1da11a3b6c459f0
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not 5 * use this file except in compliance with the License. You may obtain a copy of 6 * the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 13 * License for the specific language governing permissions and limitations under 14 * the License. 15 */ 16package android.speech.tts; 17 18import android.app.Service; 19import android.content.Intent; 20import android.net.Uri; 21import android.os.Bundle; 22import android.os.Handler; 23import android.os.HandlerThread; 24import android.os.IBinder; 25import android.os.Looper; 26import android.os.Message; 27import android.os.MessageQueue; 28import android.os.RemoteCallbackList; 29import android.os.RemoteException; 30import android.provider.Settings; 31import android.speech.tts.TextToSpeech.Engine; 32import android.text.TextUtils; 33import android.util.Log; 34 35import java.io.File; 36import java.io.IOException; 37import java.util.HashMap; 38import java.util.Locale; 39 40 41/** 42 * Abstract base class for TTS engine implementations. The following methods 43 * need to be implemented. 44 * 45 * <ul> 46 * <li>{@link #onIsLanguageAvailable}</li> 47 * <li>{@link #onLoadLanguage}</li> 48 * <li>{@link #onGetLanguage}</li> 49 * <li>{@link #onSynthesizeText}</li> 50 * <li>{@link #onStop}</li> 51 * </ul> 52 * 53 * The first three deal primarily with language management, and are used to 54 * query the engine for it's support for a given language and indicate to it 55 * that requests in a given language are imminent. 56 * 57 * {@link #onSynthesizeText} is central to the engine implementation. The 58 * implementation should synthesize text as per the request parameters and 59 * return synthesized data via the supplied callback. This class and its helpers 60 * will then consume that data, which might mean queueing it for playback or writing 61 * it to a file or similar. All calls to this method will be on a single 62 * thread, which will be different from the main thread of the service. Synthesis 63 * must be synchronous which means the engine must NOT hold on the callback or call 64 * any methods on it after the method returns 65 * 66 * {@link #onStop} tells the engine that it should stop all ongoing synthesis, if 67 * any. Any pending data from the current synthesis will be discarded. 68 */ 69// TODO: Add a link to the sample TTS engine once it's done. 70public abstract class TextToSpeechService extends Service { 71 72 private static final boolean DBG = false; 73 private static final String TAG = "TextToSpeechService"; 74 75 private static final int MAX_SPEECH_ITEM_CHAR_LENGTH = 4000; 76 private static final String SYNTH_THREAD_NAME = "SynthThread"; 77 78 private SynthHandler mSynthHandler; 79 // A thread and it's associated handler for playing back any audio 80 // associated with this TTS engine. Will handle all requests except synthesis 81 // to file requests, which occur on the synthesis thread. 82 private AudioPlaybackHandler mAudioPlaybackHandler; 83 84 private CallbackMap mCallbacks; 85 86 private int mDefaultAvailability = TextToSpeech.LANG_NOT_SUPPORTED; 87 88 @Override 89 public void onCreate() { 90 if (DBG) Log.d(TAG, "onCreate()"); 91 super.onCreate(); 92 93 SynthThread synthThread = new SynthThread(); 94 synthThread.start(); 95 mSynthHandler = new SynthHandler(synthThread.getLooper()); 96 97 mAudioPlaybackHandler = new AudioPlaybackHandler(); 98 mAudioPlaybackHandler.start(); 99 100 mCallbacks = new CallbackMap(); 101 102 // Load default language 103 mDefaultAvailability = onLoadLanguage(getDefaultLanguage(), 104 getDefaultCountry(), getDefaultVariant()); 105 } 106 107 @Override 108 public void onDestroy() { 109 if (DBG) Log.d(TAG, "onDestroy()"); 110 111 // Tell the synthesizer to stop 112 mSynthHandler.quit(); 113 // Tell the audio playback thread to stop. 114 mAudioPlaybackHandler.quit(); 115 // Unregister all callbacks. 116 mCallbacks.kill(); 117 118 super.onDestroy(); 119 } 120 121 /** 122 * Checks whether the engine supports a given language. 123 * 124 * Can be called on multiple threads. 125 * 126 * @param lang ISO-3 language code. 127 * @param country ISO-3 country code. May be empty or null. 128 * @param variant Language variant. May be empty or null. 129 * @return Code indicating the support status for the locale. 130 * One of {@link TextToSpeech#LANG_AVAILABLE}, 131 * {@link TextToSpeech#LANG_COUNTRY_AVAILABLE}, 132 * {@link TextToSpeech#LANG_COUNTRY_VAR_AVAILABLE}, 133 * {@link TextToSpeech#LANG_MISSING_DATA} 134 * {@link TextToSpeech#LANG_NOT_SUPPORTED}. 135 */ 136 protected abstract int onIsLanguageAvailable(String lang, String country, String variant); 137 138 /** 139 * Returns the language, country and variant currently being used by the TTS engine. 140 * 141 * Can be called on multiple threads. 142 * 143 * @return A 3-element array, containing language (ISO 3-letter code), 144 * country (ISO 3-letter code) and variant used by the engine. 145 * The country and variant may be {@code ""}. If country is empty, then variant must 146 * be empty too. 147 * @see Locale#getISO3Language() 148 * @see Locale#getISO3Country() 149 * @see Locale#getVariant() 150 */ 151 protected abstract String[] onGetLanguage(); 152 153 /** 154 * Notifies the engine that it should load a speech synthesis language. There is no guarantee 155 * that this method is always called before the language is used for synthesis. It is merely 156 * a hint to the engine that it will probably get some synthesis requests for this language 157 * at some point in the future. 158 * 159 * Can be called on multiple threads. 160 * 161 * @param lang ISO-3 language code. 162 * @param country ISO-3 country code. May be empty or null. 163 * @param variant Language variant. May be empty or null. 164 * @return Code indicating the support status for the locale. 165 * One of {@link TextToSpeech#LANG_AVAILABLE}, 166 * {@link TextToSpeech#LANG_COUNTRY_AVAILABLE}, 167 * {@link TextToSpeech#LANG_COUNTRY_VAR_AVAILABLE}, 168 * {@link TextToSpeech#LANG_MISSING_DATA} 169 * {@link TextToSpeech#LANG_NOT_SUPPORTED}. 170 */ 171 protected abstract int onLoadLanguage(String lang, String country, String variant); 172 173 /** 174 * Notifies the service that it should stop any in-progress speech synthesis. 175 * This method can be called even if no speech synthesis is currently in progress. 176 * 177 * Can be called on multiple threads, but not on the synthesis thread. 178 */ 179 protected abstract void onStop(); 180 181 /** 182 * Tells the service to synthesize speech from the given text. This method should 183 * block until the synthesis is finished. 184 * 185 * Called on the synthesis thread. 186 * 187 * @param request The synthesis request. 188 * @param callback The callback the the engine must use to make data available for 189 * playback or for writing to a file. 190 */ 191 protected abstract void onSynthesizeText(SynthesisRequest request, 192 SynthesisCallback callback); 193 194 private int getDefaultSpeechRate() { 195 return getSecureSettingInt(Settings.Secure.TTS_DEFAULT_RATE, Engine.DEFAULT_RATE); 196 } 197 198 private String getDefaultLanguage() { 199 return getSecureSettingString(Settings.Secure.TTS_DEFAULT_LANG, 200 Locale.getDefault().getISO3Language()); 201 } 202 203 private String getDefaultCountry() { 204 return getSecureSettingString(Settings.Secure.TTS_DEFAULT_COUNTRY, 205 Locale.getDefault().getISO3Country()); 206 } 207 208 private String getDefaultVariant() { 209 return getSecureSettingString(Settings.Secure.TTS_DEFAULT_VARIANT, 210 Locale.getDefault().getVariant()); 211 } 212 213 private int getSecureSettingInt(String name, int defaultValue) { 214 return Settings.Secure.getInt(getContentResolver(), name, defaultValue); 215 } 216 217 private String getSecureSettingString(String name, String defaultValue) { 218 String value = Settings.Secure.getString(getContentResolver(), name); 219 return value != null ? value : defaultValue; 220 } 221 222 /** 223 * Synthesizer thread. This thread is used to run {@link SynthHandler}. 224 */ 225 private class SynthThread extends HandlerThread implements MessageQueue.IdleHandler { 226 227 private boolean mFirstIdle = true; 228 229 public SynthThread() { 230 super(SYNTH_THREAD_NAME, android.os.Process.THREAD_PRIORITY_AUDIO); 231 } 232 233 @Override 234 protected void onLooperPrepared() { 235 getLooper().getQueue().addIdleHandler(this); 236 } 237 238 @Override 239 public boolean queueIdle() { 240 if (mFirstIdle) { 241 mFirstIdle = false; 242 } else { 243 broadcastTtsQueueProcessingCompleted(); 244 } 245 return true; 246 } 247 248 private void broadcastTtsQueueProcessingCompleted() { 249 Intent i = new Intent(TextToSpeech.ACTION_TTS_QUEUE_PROCESSING_COMPLETED); 250 if (DBG) Log.d(TAG, "Broadcasting: " + i); 251 sendBroadcast(i); 252 } 253 } 254 255 private class SynthHandler extends Handler { 256 257 private SpeechItem mCurrentSpeechItem = null; 258 259 public SynthHandler(Looper looper) { 260 super(looper); 261 } 262 263 private synchronized SpeechItem getCurrentSpeechItem() { 264 return mCurrentSpeechItem; 265 } 266 267 private synchronized SpeechItem setCurrentSpeechItem(SpeechItem speechItem) { 268 SpeechItem old = mCurrentSpeechItem; 269 mCurrentSpeechItem = speechItem; 270 return old; 271 } 272 273 public boolean isSpeaking() { 274 return getCurrentSpeechItem() != null; 275 } 276 277 public void quit() { 278 // Don't process any more speech items 279 getLooper().quit(); 280 // Stop the current speech item 281 SpeechItem current = setCurrentSpeechItem(null); 282 if (current != null) { 283 current.stop(); 284 } 285 } 286 287 /** 288 * Adds a speech item to the queue. 289 * 290 * Called on a service binder thread. 291 */ 292 public int enqueueSpeechItem(int queueMode, final SpeechItem speechItem) { 293 if (!speechItem.isValid()) { 294 return TextToSpeech.ERROR; 295 } 296 297 if (queueMode == TextToSpeech.QUEUE_FLUSH) { 298 stop(speechItem.getCallingApp()); 299 } else if (queueMode == TextToSpeech.QUEUE_DESTROY) { 300 // Stop the current speech item. 301 stop(speechItem.getCallingApp()); 302 // Remove all other items from the queue. 303 removeCallbacksAndMessages(null); 304 // Remove all pending playback as well. 305 mAudioPlaybackHandler.removeAllItems(); 306 } 307 Runnable runnable = new Runnable() { 308 @Override 309 public void run() { 310 setCurrentSpeechItem(speechItem); 311 speechItem.play(); 312 setCurrentSpeechItem(null); 313 } 314 }; 315 Message msg = Message.obtain(this, runnable); 316 // The obj is used to remove all callbacks from the given app in stop(String). 317 // 318 // Note that this string is interned, so the == comparison works. 319 msg.obj = speechItem.getCallingApp(); 320 if (sendMessage(msg)) { 321 return TextToSpeech.SUCCESS; 322 } else { 323 Log.w(TAG, "SynthThread has quit"); 324 return TextToSpeech.ERROR; 325 } 326 } 327 328 /** 329 * Stops all speech output and removes any utterances still in the queue for 330 * the calling app. 331 * 332 * Called on a service binder thread. 333 */ 334 public int stop(String callingApp) { 335 if (TextUtils.isEmpty(callingApp)) { 336 return TextToSpeech.ERROR; 337 } 338 339 removeCallbacksAndMessages(callingApp); 340 SpeechItem current = setCurrentSpeechItem(null); 341 if (current != null && TextUtils.equals(callingApp, current.getCallingApp())) { 342 current.stop(); 343 } 344 345 // Remove any enqueued audio too. 346 mAudioPlaybackHandler.removePlaybackItems(callingApp); 347 348 return TextToSpeech.SUCCESS; 349 } 350 } 351 352 interface UtteranceCompletedDispatcher { 353 public void dispatchUtteranceCompleted(); 354 } 355 356 /** 357 * An item in the synth thread queue. 358 */ 359 private abstract class SpeechItem implements UtteranceCompletedDispatcher { 360 private final String mCallingApp; 361 protected final Bundle mParams; 362 private boolean mStarted = false; 363 private boolean mStopped = false; 364 365 public SpeechItem(String callingApp, Bundle params) { 366 mCallingApp = callingApp; 367 mParams = params; 368 } 369 370 public String getCallingApp() { 371 return mCallingApp; 372 } 373 374 /** 375 * Checker whether the item is valid. If this method returns false, the item should not 376 * be played. 377 */ 378 public abstract boolean isValid(); 379 380 /** 381 * Plays the speech item. Blocks until playback is finished. 382 * Must not be called more than once. 383 * 384 * Only called on the synthesis thread. 385 * 386 * @return {@link TextToSpeech#SUCCESS} or {@link TextToSpeech#ERROR}. 387 */ 388 public int play() { 389 synchronized (this) { 390 if (mStarted) { 391 throw new IllegalStateException("play() called twice"); 392 } 393 mStarted = true; 394 } 395 return playImpl(); 396 } 397 398 /** 399 * Stops the speech item. 400 * Must not be called more than once. 401 * 402 * Can be called on multiple threads, but not on the synthesis thread. 403 */ 404 public void stop() { 405 synchronized (this) { 406 if (mStopped) { 407 throw new IllegalStateException("stop() called twice"); 408 } 409 mStopped = true; 410 } 411 stopImpl(); 412 } 413 414 public void dispatchUtteranceCompleted() { 415 final String utteranceId = getUtteranceId(); 416 if (!TextUtils.isEmpty(utteranceId)) { 417 mCallbacks.dispatchUtteranceCompleted(getCallingApp(), utteranceId); 418 } 419 } 420 421 protected abstract int playImpl(); 422 423 protected abstract void stopImpl(); 424 425 public int getStreamType() { 426 return getIntParam(Engine.KEY_PARAM_STREAM, Engine.DEFAULT_STREAM); 427 } 428 429 public float getVolume() { 430 return getFloatParam(Engine.KEY_PARAM_VOLUME, Engine.DEFAULT_VOLUME); 431 } 432 433 public float getPan() { 434 return getFloatParam(Engine.KEY_PARAM_PAN, Engine.DEFAULT_PAN); 435 } 436 437 public String getUtteranceId() { 438 return getStringParam(Engine.KEY_PARAM_UTTERANCE_ID, null); 439 } 440 441 protected String getStringParam(String key, String defaultValue) { 442 return mParams == null ? defaultValue : mParams.getString(key, defaultValue); 443 } 444 445 protected int getIntParam(String key, int defaultValue) { 446 return mParams == null ? defaultValue : mParams.getInt(key, defaultValue); 447 } 448 449 protected float getFloatParam(String key, float defaultValue) { 450 return mParams == null ? defaultValue : mParams.getFloat(key, defaultValue); 451 } 452 } 453 454 class SynthesisSpeechItem extends SpeechItem { 455 private final String mText; 456 private final SynthesisRequest mSynthesisRequest; 457 // Non null after synthesis has started, and all accesses 458 // guarded by 'this'. 459 private AbstractSynthesisCallback mSynthesisCallback; 460 461 public SynthesisSpeechItem(String callingApp, Bundle params, String text) { 462 super(callingApp, params); 463 mText = text; 464 mSynthesisRequest = new SynthesisRequest(mText, mParams); 465 setRequestParams(mSynthesisRequest); 466 } 467 468 public String getText() { 469 return mText; 470 } 471 472 @Override 473 public boolean isValid() { 474 if (TextUtils.isEmpty(mText)) { 475 Log.w(TAG, "Got empty text"); 476 return false; 477 } 478 if (mText.length() >= MAX_SPEECH_ITEM_CHAR_LENGTH){ 479 Log.w(TAG, "Text too long: " + mText.length() + " chars"); 480 return false; 481 } 482 return true; 483 } 484 485 @Override 486 protected int playImpl() { 487 AbstractSynthesisCallback synthesisCallback; 488 synchronized (this) { 489 mSynthesisCallback = createSynthesisCallback(); 490 synthesisCallback = mSynthesisCallback; 491 } 492 TextToSpeechService.this.onSynthesizeText(mSynthesisRequest, synthesisCallback); 493 return synthesisCallback.isDone() ? TextToSpeech.SUCCESS : TextToSpeech.ERROR; 494 } 495 496 protected AbstractSynthesisCallback createSynthesisCallback() { 497 return new PlaybackSynthesisCallback(getStreamType(), getVolume(), getPan(), 498 mAudioPlaybackHandler, this, getCallingApp()); 499 } 500 501 private void setRequestParams(SynthesisRequest request) { 502 request.setLanguage(getLanguage(), getCountry(), getVariant()); 503 request.setSpeechRate(getSpeechRate()); 504 505 request.setPitch(getPitch()); 506 } 507 508 @Override 509 protected void stopImpl() { 510 AbstractSynthesisCallback synthesisCallback; 511 synchronized (this) { 512 synthesisCallback = mSynthesisCallback; 513 } 514 synthesisCallback.stop(); 515 TextToSpeechService.this.onStop(); 516 } 517 518 public String getLanguage() { 519 return getStringParam(Engine.KEY_PARAM_LANGUAGE, getDefaultLanguage()); 520 } 521 522 private boolean hasLanguage() { 523 return !TextUtils.isEmpty(getStringParam(Engine.KEY_PARAM_LANGUAGE, null)); 524 } 525 526 private String getCountry() { 527 if (!hasLanguage()) return getDefaultCountry(); 528 return getStringParam(Engine.KEY_PARAM_COUNTRY, ""); 529 } 530 531 private String getVariant() { 532 if (!hasLanguage()) return getDefaultVariant(); 533 return getStringParam(Engine.KEY_PARAM_VARIANT, ""); 534 } 535 536 private int getSpeechRate() { 537 return getIntParam(Engine.KEY_PARAM_RATE, getDefaultSpeechRate()); 538 } 539 540 private int getPitch() { 541 return getIntParam(Engine.KEY_PARAM_PITCH, Engine.DEFAULT_PITCH); 542 } 543 } 544 545 private class SynthesisToFileSpeechItem extends SynthesisSpeechItem { 546 private final File mFile; 547 548 public SynthesisToFileSpeechItem(String callingApp, Bundle params, String text, 549 File file) { 550 super(callingApp, params, text); 551 mFile = file; 552 } 553 554 @Override 555 public boolean isValid() { 556 if (!super.isValid()) { 557 return false; 558 } 559 return checkFile(mFile); 560 } 561 562 @Override 563 protected AbstractSynthesisCallback createSynthesisCallback() { 564 return new FileSynthesisCallback(mFile); 565 } 566 567 @Override 568 protected int playImpl() { 569 int status = super.playImpl(); 570 if (status == TextToSpeech.SUCCESS) { 571 dispatchUtteranceCompleted(); 572 } 573 return status; 574 } 575 576 /** 577 * Checks that the given file can be used for synthesis output. 578 */ 579 private boolean checkFile(File file) { 580 try { 581 if (file.exists()) { 582 Log.v(TAG, "File " + file + " exists, deleting."); 583 if (!file.delete()) { 584 Log.e(TAG, "Failed to delete " + file); 585 return false; 586 } 587 } 588 if (!file.createNewFile()) { 589 Log.e(TAG, "Can't create file " + file); 590 return false; 591 } 592 if (!file.delete()) { 593 Log.e(TAG, "Failed to delete " + file); 594 return false; 595 } 596 return true; 597 } catch (IOException e) { 598 Log.e(TAG, "Can't use " + file + " due to exception " + e); 599 return false; 600 } 601 } 602 } 603 604 private class AudioSpeechItem extends SpeechItem { 605 606 private final BlockingMediaPlayer mPlayer; 607 private AudioMessageParams mToken; 608 609 public AudioSpeechItem(String callingApp, Bundle params, Uri uri) { 610 super(callingApp, params); 611 mPlayer = new BlockingMediaPlayer(TextToSpeechService.this, uri, getStreamType()); 612 } 613 614 @Override 615 public boolean isValid() { 616 return true; 617 } 618 619 @Override 620 protected int playImpl() { 621 mToken = new AudioMessageParams(this, getCallingApp(), mPlayer); 622 mAudioPlaybackHandler.enqueueAudio(mToken); 623 return TextToSpeech.SUCCESS; 624 } 625 626 @Override 627 protected void stopImpl() { 628 if (mToken != null) { 629 mAudioPlaybackHandler.stop(mToken); 630 } 631 } 632 } 633 634 private class SilenceSpeechItem extends SpeechItem { 635 private final long mDuration; 636 private SilenceMessageParams mToken; 637 638 public SilenceSpeechItem(String callingApp, Bundle params, long duration) { 639 super(callingApp, params); 640 mDuration = duration; 641 } 642 643 @Override 644 public boolean isValid() { 645 return true; 646 } 647 648 @Override 649 protected int playImpl() { 650 mToken = new SilenceMessageParams(this, getCallingApp(), mDuration); 651 mAudioPlaybackHandler.enqueueSilence(mToken); 652 return TextToSpeech.SUCCESS; 653 } 654 655 @Override 656 protected void stopImpl() { 657 if (mToken != null) { 658 mAudioPlaybackHandler.stop(mToken); 659 } 660 } 661 } 662 663 @Override 664 public IBinder onBind(Intent intent) { 665 if (TextToSpeech.Engine.INTENT_ACTION_TTS_SERVICE.equals(intent.getAction())) { 666 return mBinder; 667 } 668 return null; 669 } 670 671 /** 672 * Binder returned from {@code #onBind(Intent)}. The methods in this class can be 673 * called called from several different threads. 674 */ 675 // NOTE: All calls that are passed in a calling app are interned so that 676 // they can be used as message objects (which are tested for equality using ==). 677 private final ITextToSpeechService.Stub mBinder = new ITextToSpeechService.Stub() { 678 679 public int speak(String callingApp, String text, int queueMode, Bundle params) { 680 if (!checkNonNull(callingApp, text, params)) { 681 return TextToSpeech.ERROR; 682 } 683 684 SpeechItem item = new SynthesisSpeechItem(intern(callingApp), params, text); 685 return mSynthHandler.enqueueSpeechItem(queueMode, item); 686 } 687 688 public int synthesizeToFile(String callingApp, String text, String filename, 689 Bundle params) { 690 if (!checkNonNull(callingApp, text, filename, params)) { 691 return TextToSpeech.ERROR; 692 } 693 694 File file = new File(filename); 695 SpeechItem item = new SynthesisToFileSpeechItem(intern(callingApp), 696 params, text, file); 697 return mSynthHandler.enqueueSpeechItem(TextToSpeech.QUEUE_ADD, item); 698 } 699 700 public int playAudio(String callingApp, Uri audioUri, int queueMode, Bundle params) { 701 if (!checkNonNull(callingApp, audioUri, params)) { 702 return TextToSpeech.ERROR; 703 } 704 705 SpeechItem item = new AudioSpeechItem(intern(callingApp), params, audioUri); 706 return mSynthHandler.enqueueSpeechItem(queueMode, item); 707 } 708 709 public int playSilence(String callingApp, long duration, int queueMode, Bundle params) { 710 if (!checkNonNull(callingApp, params)) { 711 return TextToSpeech.ERROR; 712 } 713 714 SpeechItem item = new SilenceSpeechItem(intern(callingApp), params, duration); 715 return mSynthHandler.enqueueSpeechItem(queueMode, item); 716 } 717 718 public boolean isSpeaking() { 719 return mSynthHandler.isSpeaking(); 720 } 721 722 public int stop(String callingApp) { 723 if (!checkNonNull(callingApp)) { 724 return TextToSpeech.ERROR; 725 } 726 727 return mSynthHandler.stop(intern(callingApp)); 728 } 729 730 public String[] getLanguage() { 731 return onGetLanguage(); 732 } 733 734 /* 735 * If defaults are enforced, then no language is "available" except 736 * perhaps the default language selected by the user. 737 */ 738 public int isLanguageAvailable(String lang, String country, String variant) { 739 if (!checkNonNull(lang)) { 740 return TextToSpeech.ERROR; 741 } 742 743 return onIsLanguageAvailable(lang, country, variant); 744 } 745 746 /* 747 * There is no point loading a non default language if defaults 748 * are enforced. 749 */ 750 public int loadLanguage(String lang, String country, String variant) { 751 if (!checkNonNull(lang)) { 752 return TextToSpeech.ERROR; 753 } 754 755 return onLoadLanguage(lang, country, variant); 756 } 757 758 public void setCallback(String packageName, ITextToSpeechCallback cb) { 759 // Note that passing in a null callback is a valid use case. 760 if (!checkNonNull(packageName)) { 761 return; 762 } 763 764 mCallbacks.setCallback(packageName, cb); 765 } 766 767 private boolean isDefault(String lang, String country, String variant) { 768 return Locale.getDefault().equals(new Locale(lang, country, variant)); 769 } 770 771 private String intern(String in) { 772 // The input parameter will be non null. 773 return in.intern(); 774 } 775 776 private boolean checkNonNull(Object... args) { 777 for (Object o : args) { 778 if (o == null) return false; 779 } 780 return true; 781 } 782 }; 783 784 private class CallbackMap extends RemoteCallbackList<ITextToSpeechCallback> { 785 786 private final HashMap<String, ITextToSpeechCallback> mAppToCallback 787 = new HashMap<String, ITextToSpeechCallback>(); 788 789 public void setCallback(String packageName, ITextToSpeechCallback cb) { 790 synchronized (mAppToCallback) { 791 ITextToSpeechCallback old; 792 if (cb != null) { 793 register(cb, packageName); 794 old = mAppToCallback.put(packageName, cb); 795 } else { 796 old = mAppToCallback.remove(packageName); 797 } 798 if (old != null && old != cb) { 799 unregister(old); 800 } 801 } 802 } 803 804 public void dispatchUtteranceCompleted(String packageName, String utteranceId) { 805 ITextToSpeechCallback cb; 806 synchronized (mAppToCallback) { 807 cb = mAppToCallback.get(packageName); 808 } 809 if (cb == null) return; 810 try { 811 cb.utteranceCompleted(utteranceId); 812 } catch (RemoteException e) { 813 Log.e(TAG, "Callback failed: " + e); 814 } 815 } 816 817 @Override 818 public void onCallbackDied(ITextToSpeechCallback callback, Object cookie) { 819 String packageName = (String) cookie; 820 synchronized (mAppToCallback) { 821 mAppToCallback.remove(packageName); 822 } 823 mSynthHandler.stop(packageName); 824 } 825 826 @Override 827 public void kill() { 828 synchronized (mAppToCallback) { 829 mAppToCallback.clear(); 830 super.kill(); 831 } 832 } 833 834 } 835 836} 837