1 /*
   2  * Copyright (c) 1999, 2014, 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 package javax.sound.sampled;
  27 
  28 import java.io.File;
  29 import java.io.InputStream;
  30 import java.io.IOException;
  31 import java.io.OutputStream;
  32 import java.net.URL;
  33 
  34 import java.util.HashSet;
  35 import java.util.List;
  36 import java.util.Set;
  37 import java.util.Vector;
  38 import java.util.ArrayList;
  39 
  40 import javax.sound.sampled.spi.AudioFileWriter;
  41 import javax.sound.sampled.spi.AudioFileReader;
  42 import javax.sound.sampled.spi.FormatConversionProvider;
  43 import javax.sound.sampled.spi.MixerProvider;
  44 
  45 import com.sun.media.sound.JDK13Services;
  46 
  47 /* $fb TODO:
  48  * - consistent usage of (typed) collections
  49  */
  50 
  51 
  52 /**
  53  * The {@code AudioSystem} class acts as the entry point to the sampled-audio
  54  * system resources. This class lets you query and access the mixers that are
  55  * installed on the system. {@code AudioSystem} includes a number of methods for
  56  * converting audio data between different formats, and for translating between
  57  * audio files and streams. It also provides a method for obtaining a
  58  * {@link Line} directly from the {@code AudioSystem} without dealing explicitly
  59  * with mixers.
  60  * <p>
  61  * Properties can be used to specify the default mixer for specific line types.
  62  * Both system properties and a properties file are considered. The
  63  * {@code sound.properties} properties file is read from an
  64  * implementation-specific location (typically it is the {@code lib} directory
  65  * in the Java installation directory). If a property exists both as a system
  66  * property and in the properties file, the system property takes precedence.
  67  * If none is specified, a suitable default is chosen among the available
  68  * devices. The syntax of the properties file is specified in
  69  * {@link java.util.Properties#load(InputStream) Properties.load}. The following
  70  * table lists the available property keys and which methods consider them:
  71  *
  72  * <table border=0>
  73  *  <caption>Audio System Property Keys</caption>
  74  *  <tr>
  75  *   <th>Property Key</th>
  76  *   <th>Interface</th>
  77  *   <th>Affected Method(s)</th>
  78  *  </tr>
  79  *  <tr>
  80  *   <td>{@code javax.sound.sampled.Clip}</td>
  81  *   <td>{@link Clip}</td>
  82  *   <td>{@link #getLine}, {@link #getClip}</td>
  83  *  </tr>
  84  *  <tr>
  85  *   <td>{@code javax.sound.sampled.Port}</td>
  86  *   <td>{@link Port}</td>
  87  *   <td>{@link #getLine}</td>
  88  *  </tr>
  89  *  <tr>
  90  *   <td>{@code javax.sound.sampled.SourceDataLine}</td>
  91  *   <td>{@link SourceDataLine}</td>
  92  *   <td>{@link #getLine}, {@link #getSourceDataLine}</td>
  93  *  </tr>
  94  *  <tr>
  95  *   <td>{@code javax.sound.sampled.TargetDataLine}</td>
  96  *   <td>{@link TargetDataLine}</td>
  97  *   <td>{@link #getLine}, {@link #getTargetDataLine}</td>
  98  *  </tr>
  99  * </table>
 100  *
 101  * The property value consists of the provider class name and the mixer name,
 102  * separated by the hash mark (&quot;#&quot;). The provider class name is the
 103  * fully-qualified name of a concrete
 104  * {@link javax.sound.sampled.spi.MixerProvider mixer provider} class. The mixer
 105  * name is matched against the {@code String} returned by the {@code getName}
 106  * method of {@code Mixer.Info}. Either the class name, or the mixer name may be
 107  * omitted. If only the class name is specified, the trailing hash mark is
 108  * optional.
 109  * <p>
 110  * If the provider class is specified, and it can be successfully retrieved from
 111  * the installed providers, the list of {@code Mixer.Info} objects is retrieved
 112  * from the provider. Otherwise, or when these mixers do not provide a
 113  * subsequent match, the list is retrieved from {@link #getMixerInfo} to contain
 114  * all available {@code Mixer.Info} objects.
 115  * <p>
 116  * If a mixer name is specified, the resulting list of {@code Mixer.Info}
 117  * objects is searched: the first one with a matching name, and whose
 118  * {@code Mixer} provides the respective line interface, will be returned. If no
 119  * matching {@code Mixer.Info} object is found, or the mixer name is not
 120  * specified, the first mixer from the resulting list, which provides the
 121  * respective line interface, will be returned.
 122  *
 123  * For example, the property {@code javax.sound.sampled.Clip} with a value
 124  * {@code "com.sun.media.sound.MixerProvider#SunClip"}
 125  * will have the following consequences when {@code getLine} is called
 126  * requesting a {@code Clip} instance: if the class
 127  * {@code com.sun.media.sound.MixerProvider} exists in the list of installed
 128  * mixer providers, the first {@code Clip} from the first mixer with name
 129  * {@code "SunClip"} will be returned. If it cannot be found, the
 130  * first {@code Clip} from the first mixer of the specified provider will be
 131  * returned, regardless of name. If there is none, the first {@code Clip} from
 132  * the first {@code Mixer} with name {@code "SunClip"} in the list of
 133  * all mixers (as returned by {@code getMixerInfo}) will be returned, or, if not
 134  * found, the first {@code Clip} of the first {@code Mixer} that can be found in
 135  * the list of all mixers is returned. If that fails, too, an
 136  * {@code IllegalArgumentException} is thrown.
 137  *
 138  * @author Kara Kytle
 139  * @author Florian Bomers
 140  * @author Matthias Pfisterer
 141  * @author Kevin P. Smith
 142  * @see AudioFormat
 143  * @see AudioInputStream
 144  * @see Mixer
 145  * @see Line
 146  * @see Line.Info
 147  * @since 1.3
 148  */
 149 public class AudioSystem {
 150 
 151     /**
 152      * An integer that stands for an unknown numeric value. This value is
 153      * appropriate only for signed quantities that do not normally take negative
 154      * values. Examples include file sizes, frame sizes, buffer sizes, and
 155      * sample rates. A number of Java Sound constructors accept a value of
 156      * {@code NOT_SPECIFIED} for such parameters. Other methods may also accept
 157      * or return this value, as documented.
 158      */
 159     public static final int NOT_SPECIFIED = -1;
 160 
 161     /**
 162      * Private no-args constructor for ensuring against instantiation.
 163      */
 164     private AudioSystem() {
 165     }
 166 
 167     /**
 168      * Obtains an array of mixer info objects that represents the set of audio
 169      * mixers that are currently installed on the system.
 170      *
 171      * @return an array of info objects for the currently installed mixers. If
 172      *         no mixers are available on the system, an array of length 0 is
 173      *         returned.
 174      * @see #getMixer
 175      */
 176     public static Mixer.Info[] getMixerInfo() {
 177 
 178         List infos = getMixerInfoList();
 179         Mixer.Info[] allInfos = (Mixer.Info[]) infos.toArray(new Mixer.Info[infos.size()]);
 180         return allInfos;
 181     }
 182 
 183     /**
 184      * Obtains the requested audio mixer.
 185      *
 186      * @param  info a {@code Mixer.Info} object representing the desired mixer,
 187      *         or {@code null} for the system default mixer
 188      * @return the requested mixer
 189      * @throws SecurityException if the requested mixer is unavailable because
 190      *         of security restrictions
 191      * @throws IllegalArgumentException if the info object does not represent a
 192      *         mixer installed on the system
 193      * @see #getMixerInfo
 194      */
 195     public static Mixer getMixer(Mixer.Info info) {
 196 
 197         Mixer mixer = null;
 198         List providers = getMixerProviders();
 199 
 200         for(int i = 0; i < providers.size(); i++ ) {
 201 
 202             try {
 203                 return ((MixerProvider)providers.get(i)).getMixer(info);
 204 
 205             } catch (IllegalArgumentException e) {
 206             } catch (NullPointerException e) {
 207                 // $$jb 08.20.99:  If the strings in the info object aren't
 208                 // set, then Netscape (using jdk1.1.5) tends to throw
 209                 // NPE's when doing some string manipulation.  This is
 210                 // probably not the best fix, but is solves the problem
 211                 // of the NPE in Netscape using local classes
 212                 // $$jb 11.01.99: Replacing this patch.
 213             }
 214         }
 215 
 216         //$$fb if looking for default mixer, and not found yet, add a round of looking
 217         if (info == null) {
 218             for(int i = 0; i < providers.size(); i++ ) {
 219                 try {
 220                     MixerProvider provider = (MixerProvider) providers.get(i);
 221                     Mixer.Info[] infos = provider.getMixerInfo();
 222                     // start from 0 to last device (do not reverse this order)
 223                     for (int ii = 0; ii < infos.length; ii++) {
 224                         try {
 225                             return provider.getMixer(infos[ii]);
 226                         } catch (IllegalArgumentException e) {
 227                             // this is not a good default device :)
 228                         }
 229                     }
 230                 } catch (IllegalArgumentException e) {
 231                 } catch (NullPointerException e) {
 232                 }
 233             }
 234         }
 235 
 236 
 237         throw new IllegalArgumentException("Mixer not supported: "
 238                                            + (info!=null?info.toString():"null"));
 239     }
 240 
 241     //$$fb 2002-11-26: fix for 4757930: DOC: AudioSystem.getTarget/SourceLineInfo() is ambiguous
 242 
 243     /**
 244      * Obtains information about all source lines of a particular type that are
 245      * supported by the installed mixers.
 246      *
 247      * @param  info a {@code Line.Info} object that specifies the kind of lines
 248      *         about which information is requested
 249      * @return an array of {@code Line.Info} objects describing source lines
 250      *         matching the type requested. If no matching source lines are
 251      *         supported, an array of length 0 is returned.
 252      * @see Mixer#getSourceLineInfo(Line.Info)
 253      */
 254     public static Line.Info[] getSourceLineInfo(Line.Info info) {
 255 
 256         Vector vector = new Vector();
 257         Line.Info[] currentInfoArray;
 258 
 259         Mixer mixer;
 260         Line.Info fullInfo = null;
 261         Mixer.Info[] infoArray = getMixerInfo();
 262 
 263         for (int i = 0; i < infoArray.length; i++) {
 264 
 265             mixer = getMixer(infoArray[i]);
 266 
 267             currentInfoArray = mixer.getSourceLineInfo(info);
 268             for (int j = 0; j < currentInfoArray.length; j++) {
 269                 vector.addElement(currentInfoArray[j]);
 270             }
 271         }
 272 
 273         Line.Info[] returnedArray = new Line.Info[vector.size()];
 274 
 275         for (int i = 0; i < returnedArray.length; i++) {
 276             returnedArray[i] = (Line.Info)vector.get(i);
 277         }
 278 
 279         return returnedArray;
 280     }
 281 
 282     /**
 283      * Obtains information about all target lines of a particular type that are
 284      * supported by the installed mixers.
 285      *
 286      * @param  info a {@code Line.Info} object that specifies the kind of lines
 287      *         about which information is requested
 288      * @return an array of {@code Line.Info} objects describing target lines
 289      *         matching the type requested. If no matching target lines are
 290      *         supported, an array of length 0 is returned.
 291      * @see Mixer#getTargetLineInfo(Line.Info)
 292      */
 293     public static Line.Info[] getTargetLineInfo(Line.Info info) {
 294 
 295         Vector vector = new Vector();
 296         Line.Info[] currentInfoArray;
 297 
 298         Mixer mixer;
 299         Line.Info fullInfo = null;
 300         Mixer.Info[] infoArray = getMixerInfo();
 301 
 302         for (int i = 0; i < infoArray.length; i++) {
 303 
 304             mixer = getMixer(infoArray[i]);
 305 
 306             currentInfoArray = mixer.getTargetLineInfo(info);
 307             for (int j = 0; j < currentInfoArray.length; j++) {
 308                 vector.addElement(currentInfoArray[j]);
 309             }
 310         }
 311 
 312         Line.Info[] returnedArray = new Line.Info[vector.size()];
 313 
 314         for (int i = 0; i < returnedArray.length; i++) {
 315             returnedArray[i] = (Line.Info)vector.get(i);
 316         }
 317 
 318         return returnedArray;
 319     }
 320 
 321     /**
 322      * Indicates whether the system supports any lines that match the specified
 323      * {@code Line.Info} object. A line is supported if any installed mixer
 324      * supports it.
 325      *
 326      * @param  info a {@code Line.Info} object describing the line for which
 327      *         support is queried
 328      * @return {@code true} if at least one matching line is supported,
 329      *         otherwise {@code false}
 330      * @see Mixer#isLineSupported(Line.Info)
 331      */
 332     public static boolean isLineSupported(Line.Info info) {
 333 
 334         Mixer mixer;
 335         Mixer.Info[] infoArray = getMixerInfo();
 336 
 337         for (int i = 0; i < infoArray.length; i++) {
 338 
 339             if( infoArray[i] != null ) {
 340                 mixer = getMixer(infoArray[i]);
 341                 if (mixer.isLineSupported(info)) {
 342                     return true;
 343                 }
 344             }
 345         }
 346 
 347         return false;
 348     }
 349 
 350     /**
 351      * Obtains a line that matches the description in the specified
 352      * {@code Line.Info} object.
 353      * <p>
 354      * If a {@code DataLine} is requested, and {@code info} is an instance of
 355      * {@code DataLine.Info} specifying at least one fully qualified audio
 356      * format, the last one will be used as the default format of the returned
 357      * {@code DataLine}.
 358      * <p>
 359      * If system properties
 360      * {@code javax.sound.sampled.Clip},
 361      * {@code javax.sound.sampled.Port},
 362      * {@code javax.sound.sampled.SourceDataLine} and
 363      * {@code javax.sound.sampled.TargetDataLine} are defined or they are
 364      * defined in the file "sound.properties", they are used to retrieve default
 365      * lines. For details, refer to the {@link AudioSystem class description}.
 366      *
 367      * If the respective property is not set, or the mixer requested in the
 368      * property is not installed or does not provide the requested line, all
 369      * installed mixers are queried for the requested line type. A Line will be
 370      * returned from the first mixer providing the requested line type.
 371      *
 372      * @param  info a {@code Line.Info} object describing the desired kind of
 373      *         line
 374      * @return a line of the requested kind
 375      * @throws LineUnavailableException if a matching line is not available due
 376      *         to resource restrictions
 377      * @throws SecurityException if a matching line is not available due to
 378      *         security restrictions
 379      * @throws IllegalArgumentException if the system does not support at least
 380      *         one line matching the specified {@code Line.Info} object through
 381      *         any installed mixer
 382      */
 383     public static Line getLine(Line.Info info) throws LineUnavailableException {
 384         LineUnavailableException lue = null;
 385         List providers = getMixerProviders();
 386 
 387 
 388         // 1: try from default mixer for this line class
 389         try {
 390             Mixer mixer = getDefaultMixer(providers, info);
 391             if (mixer != null && mixer.isLineSupported(info)) {
 392                 return mixer.getLine(info);
 393             }
 394         } catch (LineUnavailableException e) {
 395             lue = e;
 396         } catch (IllegalArgumentException iae) {
 397             // must not happen... but better to catch it here,
 398             // if plug-ins are badly written
 399         }
 400 
 401 
 402         // 2: if that doesn't work, try to find any mixing mixer
 403         for(int i = 0; i < providers.size(); i++) {
 404             MixerProvider provider = (MixerProvider) providers.get(i);
 405             Mixer.Info[] infos = provider.getMixerInfo();
 406 
 407             for (int j = 0; j < infos.length; j++) {
 408                 try {
 409                     Mixer mixer = provider.getMixer(infos[j]);
 410                     // see if this is an appropriate mixer which can mix
 411                     if (isAppropriateMixer(mixer, info, true)) {
 412                         return mixer.getLine(info);
 413                     }
 414                 } catch (LineUnavailableException e) {
 415                     lue = e;
 416                 } catch (IllegalArgumentException iae) {
 417                     // must not happen... but better to catch it here,
 418                     // if plug-ins are badly written
 419                 }
 420             }
 421         }
 422 
 423 
 424         // 3: if that didn't work, try to find any non-mixing mixer
 425         for(int i = 0; i < providers.size(); i++) {
 426             MixerProvider provider = (MixerProvider) providers.get(i);
 427             Mixer.Info[] infos = provider.getMixerInfo();
 428             for (int j = 0; j < infos.length; j++) {
 429                 try {
 430                     Mixer mixer = provider.getMixer(infos[j]);
 431                     // see if this is an appropriate mixer which can mix
 432                     if (isAppropriateMixer(mixer, info, false)) {
 433                         return mixer.getLine(info);
 434                     }
 435                 } catch (LineUnavailableException e) {
 436                     lue = e;
 437                 } catch (IllegalArgumentException iae) {
 438                     // must not happen... but better to catch it here,
 439                     // if plug-ins are badly written
 440                 }
 441             }
 442         }
 443 
 444         // if this line was supported but was not available, throw the last
 445         // LineUnavailableException we got (??).
 446         if (lue != null) {
 447             throw lue;
 448         }
 449 
 450         // otherwise, the requested line was not supported, so throw
 451         // an Illegal argument exception
 452         throw new IllegalArgumentException("No line matching " +
 453                                            info.toString() + " is supported.");
 454     }
 455 
 456     /**
 457      * Obtains a clip that can be used for playing back an audio file or an
 458      * audio stream. The returned clip will be provided by the default system
 459      * mixer, or, if not possible, by any other mixer installed in the system
 460      * that supports a {@code Clip} object.
 461      * <p>
 462      * The returned clip must be opened with the {@code open(AudioFormat)} or
 463      * {@code open(AudioInputStream)} method.
 464      * <p>
 465      * This is a high-level method that uses {@code getMixer} and
 466      * {@code getLine} internally.
 467      * <p>
 468      * If the system property {@code javax.sound.sampled.Clip} is defined or it
 469      * is defined in the file "sound.properties", it is used to retrieve the
 470      * default clip. For details, refer to the
 471      * {@link AudioSystem class description}.
 472      *
 473      * @return the desired clip object
 474      * @throws LineUnavailableException if a clip object is not available due to
 475      *         resource restrictions
 476      * @throws SecurityException if a clip object is not available due to
 477      *         security restrictions
 478      * @throws IllegalArgumentException if the system does not support at least
 479      *         one clip instance through any installed mixer
 480      * @see #getClip(Mixer.Info)
 481      * @since 1.5
 482      */
 483     public static Clip getClip() throws LineUnavailableException{
 484         AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
 485                                              AudioSystem.NOT_SPECIFIED,
 486                                              16, 2, 4,
 487                                              AudioSystem.NOT_SPECIFIED, true);
 488         DataLine.Info info = new DataLine.Info(Clip.class, format);
 489         return (Clip) AudioSystem.getLine(info);
 490     }
 491 
 492     /**
 493      * Obtains a clip from the specified mixer that can be used for playing back
 494      * an audio file or an audio stream.
 495      * <p>
 496      * The returned clip must be opened with the {@code open(AudioFormat)} or
 497      * {@code open(AudioInputStream)} method.
 498      * <p>
 499      * This is a high-level method that uses {@code getMixer} and
 500      * {@code getLine} internally.
 501      *
 502      * @param  mixerInfo a {@code Mixer.Info} object representing the desired
 503      *         mixer, or {@code null} for the system default mixer
 504      * @return a clip object from the specified mixer
 505      *
 506      * @throws LineUnavailableException if a clip is not available from this
 507      *         mixer due to resource restrictions
 508      * @throws SecurityException if a clip is not available from this mixer due
 509      *         to security restrictions
 510      * @throws IllegalArgumentException if the system does not support at least
 511      *         one clip through the specified mixer
 512      * @see #getClip()
 513      * @since 1.5
 514      */
 515     public static Clip getClip(Mixer.Info mixerInfo) throws LineUnavailableException{
 516         AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
 517                                              AudioSystem.NOT_SPECIFIED,
 518                                              16, 2, 4,
 519                                              AudioSystem.NOT_SPECIFIED, true);
 520         DataLine.Info info = new DataLine.Info(Clip.class, format);
 521         Mixer mixer = AudioSystem.getMixer(mixerInfo);
 522         return (Clip) mixer.getLine(info);
 523     }
 524 
 525     /**
 526      * Obtains a source data line that can be used for playing back audio data
 527      * in the format specified by the {@code AudioFormat} object. The returned
 528      * line will be provided by the default system mixer, or, if not possible,
 529      * by any other mixer installed in the system that supports a matching
 530      * {@code SourceDataLine} object.
 531      * <p>
 532      * The returned line should be opened with the {@code open(AudioFormat)} or
 533      * {@code open(AudioFormat, int)} method.
 534      * <p>
 535      * This is a high-level method that uses {@code getMixer} and
 536      * {@code getLine} internally.
 537      * <p>
 538      * The returned {@code SourceDataLine}'s default audio format will be
 539      * initialized with {@code format}.
 540      * <p>
 541      * If the system property {@code javax.sound.sampled.SourceDataLine} is
 542      * defined or it is defined in the file "sound.properties", it is used to
 543      * retrieve the default source data line. For details, refer to the
 544      * {@link AudioSystem class description}.
 545      *
 546      * @param  format an {@code AudioFormat} object specifying the supported
 547      *         audio format of the returned line, or {@code null} for any audio
 548      *         format
 549      * @return the desired {@code SourceDataLine} object
 550      * @throws LineUnavailableException if a matching source data line is not
 551      *         available due to resource restrictions
 552      * @throws SecurityException if a matching source data line is not available
 553      *         due to security restrictions
 554      * @throws IllegalArgumentException if the system does not support at least
 555      *         one source data line supporting the specified audio format
 556      *         through any installed mixer
 557      * @see #getSourceDataLine(AudioFormat, Mixer.Info)
 558      * @since 1.5
 559      */
 560     public static SourceDataLine getSourceDataLine(AudioFormat format)
 561         throws LineUnavailableException{
 562         DataLine.Info info = new DataLine.Info(SourceDataLine.class, format);
 563         return (SourceDataLine) AudioSystem.getLine(info);
 564     }
 565 
 566     /**
 567      * Obtains a source data line that can be used for playing back audio data
 568      * in the format specified by the {@code AudioFormat} object, provided by
 569      * the mixer specified by the {@code Mixer.Info} object.
 570      * <p>
 571      * The returned line should be opened with the {@code open(AudioFormat)} or
 572      * {@code open(AudioFormat, int)} method.
 573      * <p>
 574      * This is a high-level method that uses {@code getMixer} and
 575      * {@code getLine} internally.
 576      * <p>
 577      * The returned {@code SourceDataLine}'s default audio format will be
 578      * initialized with {@code format}.
 579      *
 580      * @param  format an {@code AudioFormat} object specifying the supported
 581      *         audio format of the returned line, or {@code null} for any audio
 582      *         format
 583      * @param  mixerinfo a {@code Mixer.Info} object representing the desired
 584      *         mixer, or {@code null} for the system default mixer
 585      * @return the desired {@code SourceDataLine} object
 586      * @throws LineUnavailableException if a matching source data line is not
 587      *         available from the specified mixer due to resource restrictions
 588      * @throws SecurityException if a matching source data line is not available
 589      *         from the specified mixer due to security restrictions
 590      * @throws IllegalArgumentException if the specified mixer does not support
 591      *         at least one source data line supporting the specified audio
 592      *         format
 593      * @see #getSourceDataLine(AudioFormat)
 594      * @since 1.5
 595      */
 596     public static SourceDataLine getSourceDataLine(AudioFormat format,
 597                                                    Mixer.Info mixerinfo)
 598         throws LineUnavailableException{
 599         DataLine.Info info = new DataLine.Info(SourceDataLine.class, format);
 600         Mixer mixer = AudioSystem.getMixer(mixerinfo);
 601         return (SourceDataLine) mixer.getLine(info);
 602     }
 603 
 604     /**
 605      * Obtains a target data line that can be used for recording audio data in
 606      * the format specified by the {@code AudioFormat} object. The returned line
 607      * will be provided by the default system mixer, or, if not possible, by any
 608      * other mixer installed in the system that supports a matching
 609      * {@code TargetDataLine} object.
 610      * <p>
 611      * The returned line should be opened with the {@code open(AudioFormat)} or
 612      * {@code open(AudioFormat, int)} method.
 613      * <p>
 614      * This is a high-level method that uses {@code getMixer} and
 615      * {@code getLine} internally.
 616      * <p>
 617      * The returned {@code TargetDataLine}'s default audio format will be
 618      * initialized with {@code format}.
 619      * <p>
 620      * If the system property {@code javax.sound.sampled.TargetDataLine} is
 621      * defined or it is defined in the file "sound.properties", it is used to
 622      * retrieve the default target data line. For details, refer to the
 623      * {@link AudioSystem class description}.
 624      *
 625      * @param  format an {@code AudioFormat} object specifying the supported
 626      *         audio format of the returned line, or {@code null} for any audio
 627      *         format
 628      * @return the desired {@code TargetDataLine} object
 629      * @throws LineUnavailableException if a matching target data line is not
 630      *         available due to resource restrictions
 631      * @throws SecurityException if a matching target data line is not available
 632      *         due to security restrictions
 633      * @throws IllegalArgumentException if the system does not support at least
 634      *         one target data line supporting the specified audio format
 635      *         through any installed mixer
 636      * @see #getTargetDataLine(AudioFormat, Mixer.Info)
 637      * @see AudioPermission
 638      * @since 1.5
 639      */
 640     public static TargetDataLine getTargetDataLine(AudioFormat format)
 641         throws LineUnavailableException{
 642 
 643         DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
 644         return (TargetDataLine) AudioSystem.getLine(info);
 645     }
 646 
 647     /**
 648      * Obtains a target data line that can be used for recording audio data in
 649      * the format specified by the {@code AudioFormat} object, provided by the
 650      * mixer specified by the {@code Mixer.Info} object.
 651      * <p>
 652      * The returned line should be opened with the {@code open(AudioFormat)} or
 653      * {@code open(AudioFormat, int)} method.
 654      * <p>
 655      * This is a high-level method that uses {@code getMixer} and
 656      * {@code getLine} internally.
 657      * <p>
 658      * The returned {@code TargetDataLine}'s default audio format will be
 659      * initialized with {@code format}.
 660      *
 661      * @param  format an {@code AudioFormat} object specifying the supported
 662      *         audio format of the returned line, or {@code null} for any audio
 663      *         format
 664      * @param  mixerinfo a {@code Mixer.Info} object representing the desired
 665      *         mixer, or {@code null} for the system default mixer
 666      * @return the desired {@code TargetDataLine} object
 667      * @throws LineUnavailableException if a matching target data line is not
 668      *         available from the specified mixer due to resource restrictions
 669      * @throws SecurityException if a matching target data line is not available
 670      *         from the specified mixer due to security restrictions
 671      * @throws IllegalArgumentException if the specified mixer does not support
 672      *         at least one target data line supporting the specified audio
 673      *         format
 674      * @see #getTargetDataLine(AudioFormat)
 675      * @see AudioPermission
 676      * @since 1.5
 677      */
 678     public static TargetDataLine getTargetDataLine(AudioFormat format,
 679                                                    Mixer.Info mixerinfo)
 680         throws LineUnavailableException {
 681 
 682         DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
 683         Mixer mixer = AudioSystem.getMixer(mixerinfo);
 684         return (TargetDataLine) mixer.getLine(info);
 685     }
 686 
 687     // $$fb 2002-04-12: fix for 4662082: behavior of AudioSystem.getTargetEncodings() methods doesn't match the spec
 688 
 689     /**
 690      * Obtains the encodings that the system can obtain from an audio input
 691      * stream with the specified encoding using the set of installed format
 692      * converters.
 693      *
 694      * @param  sourceEncoding the encoding for which conversion support is
 695      *         queried
 696      * @return array of encodings. If {@code sourceEncoding}is not supported, an
 697      *         array of length 0 is returned. Otherwise, the array will have a
 698      *         length of at least 1, representing {@code sourceEncoding}
 699      *         (no conversion).
 700      */
 701     public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat.Encoding sourceEncoding) {
 702 
 703         List codecs = getFormatConversionProviders();
 704         Vector encodings = new Vector();
 705 
 706         AudioFormat.Encoding encs[] = null;
 707 
 708         // gather from all the codecs
 709         for(int i=0; i<codecs.size(); i++ ) {
 710             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 711             if( codec.isSourceEncodingSupported( sourceEncoding ) ) {
 712                 encs = codec.getTargetEncodings();
 713                 for (int j = 0; j < encs.length; j++) {
 714                     encodings.addElement( encs[j] );
 715                 }
 716             }
 717         }
 718         AudioFormat.Encoding encs2[] = (AudioFormat.Encoding[]) encodings.toArray(new AudioFormat.Encoding[0]);
 719         return encs2;
 720     }
 721 
 722     // $$fb 2002-04-12: fix for 4662082: behavior of AudioSystem.getTargetEncodings() methods doesn't match the spec
 723 
 724     /**
 725      * Obtains the encodings that the system can obtain from an audio input
 726      * stream with the specified format using the set of installed format
 727      * converters.
 728      *
 729      * @param  sourceFormat the audio format for which conversion is queried
 730      * @return array of encodings. If {@code sourceFormat}is not supported, an
 731      *         array of length 0 is returned. Otherwise, the array will have a
 732      *         length of at least 1, representing the encoding of
 733      *         {@code sourceFormat} (no conversion).
 734      */
 735     public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat sourceFormat) {
 736 
 737 
 738         List codecs = getFormatConversionProviders();
 739         Vector encodings = new Vector();
 740 
 741         int size = 0;
 742         int index = 0;
 743         AudioFormat.Encoding encs[] = null;
 744 
 745         // gather from all the codecs
 746 
 747         for(int i=0; i<codecs.size(); i++ ) {
 748             encs = ((FormatConversionProvider) codecs.get(i)).getTargetEncodings(sourceFormat);
 749             size += encs.length;
 750             encodings.addElement( encs );
 751         }
 752 
 753         // now build a new array
 754 
 755         AudioFormat.Encoding encs2[] = new AudioFormat.Encoding[size];
 756         for(int i=0; i<encodings.size(); i++ ) {
 757             encs = (AudioFormat.Encoding [])(encodings.get(i));
 758             for(int j=0; j<encs.length; j++ ) {
 759                 encs2[index++] = encs[j];
 760             }
 761         }
 762         return encs2;
 763     }
 764 
 765     /**
 766      * Indicates whether an audio input stream of the specified encoding can be
 767      * obtained from an audio input stream that has the specified format.
 768      *
 769      * @param  targetEncoding the desired encoding after conversion
 770      * @param  sourceFormat the audio format before conversion
 771      * @return {@code true} if the conversion is supported, otherwise
 772      *         {@code false}
 773      */
 774     public static boolean isConversionSupported(AudioFormat.Encoding targetEncoding, AudioFormat sourceFormat) {
 775 
 776 
 777         List codecs = getFormatConversionProviders();
 778 
 779         for(int i=0; i<codecs.size(); i++ ) {
 780             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 781             if(codec.isConversionSupported(targetEncoding,sourceFormat) ) {
 782                 return true;
 783             }
 784         }
 785         return false;
 786     }
 787 
 788     /**
 789      * Obtains an audio input stream of the indicated encoding, by converting
 790      * the provided audio input stream.
 791      *
 792      * @param  targetEncoding the desired encoding after conversion
 793      * @param  sourceStream the stream to be converted
 794      * @return an audio input stream of the indicated encoding
 795      * @throws IllegalArgumentException if the conversion is not supported
 796      * @see #getTargetEncodings(AudioFormat.Encoding)
 797      * @see #getTargetEncodings(AudioFormat)
 798      * @see #isConversionSupported(AudioFormat.Encoding, AudioFormat)
 799      * @see #getAudioInputStream(AudioFormat, AudioInputStream)
 800      */
 801     public static AudioInputStream getAudioInputStream(AudioFormat.Encoding targetEncoding,
 802                                                        AudioInputStream sourceStream) {
 803 
 804         List codecs = getFormatConversionProviders();
 805 
 806         for(int i = 0; i < codecs.size(); i++) {
 807             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 808             if( codec.isConversionSupported( targetEncoding, sourceStream.getFormat() ) ) {
 809                 return codec.getAudioInputStream( targetEncoding, sourceStream );
 810             }
 811         }
 812         // we ran out of options, throw an exception
 813         throw new IllegalArgumentException("Unsupported conversion: " + targetEncoding + " from " + sourceStream.getFormat());
 814     }
 815 
 816     /**
 817      * Obtains the formats that have a particular encoding and that the system
 818      * can obtain from a stream of the specified format using the set of
 819      * installed format converters.
 820      *
 821      * @param  targetEncoding the desired encoding after conversion
 822      * @param  sourceFormat the audio format before conversion
 823      * @return array of formats. If no formats of the specified encoding are
 824      *         supported, an array of length 0 is returned.
 825      */
 826     public static AudioFormat[] getTargetFormats(AudioFormat.Encoding targetEncoding, AudioFormat sourceFormat) {
 827 
 828         List codecs = getFormatConversionProviders();
 829         Vector formats = new Vector();
 830 
 831         int size = 0;
 832         int index = 0;
 833         AudioFormat fmts[] = null;
 834 
 835         // gather from all the codecs
 836 
 837         for(int i=0; i<codecs.size(); i++ ) {
 838             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 839             fmts = codec.getTargetFormats(targetEncoding, sourceFormat);
 840             size += fmts.length;
 841             formats.addElement( fmts );
 842         }
 843 
 844         // now build a new array
 845 
 846         AudioFormat fmts2[] = new AudioFormat[size];
 847         for(int i=0; i<formats.size(); i++ ) {
 848             fmts = (AudioFormat [])(formats.get(i));
 849             for(int j=0; j<fmts.length; j++ ) {
 850                 fmts2[index++] = fmts[j];
 851             }
 852         }
 853         return fmts2;
 854     }
 855 
 856     /**
 857      * Indicates whether an audio input stream of a specified format can be
 858      * obtained from an audio input stream of another specified format.
 859      *
 860      * @param  targetFormat the desired audio format after conversion
 861      * @param  sourceFormat the audio format before conversion
 862      * @return {@code true} if the conversion is supported, otherwise
 863      *         {@code false}
 864      */
 865     public static boolean isConversionSupported(AudioFormat targetFormat, AudioFormat sourceFormat) {
 866 
 867         List codecs = getFormatConversionProviders();
 868 
 869         for(int i=0; i<codecs.size(); i++ ) {
 870             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 871             if(codec.isConversionSupported(targetFormat, sourceFormat) ) {
 872                 return true;
 873             }
 874         }
 875         return false;
 876     }
 877 
 878     /**
 879      * Obtains an audio input stream of the indicated format, by converting the
 880      * provided audio input stream.
 881      *
 882      * @param  targetFormat the desired audio format after conversion
 883      * @param  sourceStream the stream to be converted
 884      * @return an audio input stream of the indicated format
 885      * @throws IllegalArgumentException if the conversion is not supported
 886      * @see #getTargetEncodings(AudioFormat)
 887      * @see #getTargetFormats(AudioFormat.Encoding, AudioFormat)
 888      * @see #isConversionSupported(AudioFormat, AudioFormat)
 889      * @see #getAudioInputStream(AudioFormat.Encoding, AudioInputStream)
 890      */
 891     public static AudioInputStream getAudioInputStream(AudioFormat targetFormat,
 892                                                        AudioInputStream sourceStream) {
 893 
 894         if (sourceStream.getFormat().matches(targetFormat)) {
 895             return sourceStream;
 896         }
 897 
 898         List codecs = getFormatConversionProviders();
 899 
 900         for(int i = 0; i < codecs.size(); i++) {
 901             FormatConversionProvider codec = (FormatConversionProvider) codecs.get(i);
 902             if(codec.isConversionSupported(targetFormat,sourceStream.getFormat()) ) {
 903                 return codec.getAudioInputStream(targetFormat,sourceStream);
 904             }
 905         }
 906 
 907         // we ran out of options...
 908         throw new IllegalArgumentException("Unsupported conversion: " + targetFormat + " from " + sourceStream.getFormat());
 909     }
 910 
 911     /**
 912      * Obtains the audio file format of the provided input stream. The stream
 913      * must point to valid audio file data. The implementation of this method
 914      * may require multiple parsers to examine the stream to determine whether
 915      * they support it. These parsers must be able to mark the stream, read
 916      * enough data to determine whether they support the stream, and, if not,
 917      * reset the stream's read pointer to its original position. If the input
 918      * stream does not support these operations, this method may fail with an
 919      * {@code IOException}.
 920      *
 921      * @param  stream the input stream from which file format information should
 922      *         be extracted
 923      * @return an {@code AudioFileFormat} object describing the stream's audio
 924      *         file format
 925      * @throws UnsupportedAudioFileException if the stream does not point to
 926      *         valid audio file data recognized by the system
 927      * @throws IOException if an input/output exception occurs
 928      * @see InputStream#markSupported
 929      * @see InputStream#mark
 930      */
 931     public static AudioFileFormat getAudioFileFormat(InputStream stream)
 932         throws UnsupportedAudioFileException, IOException {
 933 
 934         List providers = getAudioFileReaders();
 935         AudioFileFormat format = null;
 936 
 937         for(int i = 0; i < providers.size(); i++ ) {
 938             AudioFileReader reader = (AudioFileReader) providers.get(i);
 939             try {
 940                 format = reader.getAudioFileFormat( stream ); // throws IOException
 941                 break;
 942             } catch (UnsupportedAudioFileException e) {
 943                 continue;
 944             }
 945         }
 946 
 947         if( format==null ) {
 948             throw new UnsupportedAudioFileException("file is not a supported file type");
 949         } else {
 950             return format;
 951         }
 952     }
 953 
 954     /**
 955      * Obtains the audio file format of the specified URL. The URL must point to
 956      * valid audio file data.
 957      *
 958      * @param  url the URL from which file format information should be
 959      *         extracted
 960      * @return an {@code AudioFileFormat} object describing the audio file
 961      *         format
 962      * @throws UnsupportedAudioFileException if the URL does not point to valid
 963      *         audio file data recognized by the system
 964      * @throws IOException if an input/output exception occurs
 965      */
 966     public static AudioFileFormat getAudioFileFormat(URL url)
 967         throws UnsupportedAudioFileException, IOException {
 968 
 969         List providers = getAudioFileReaders();
 970         AudioFileFormat format = null;
 971 
 972         for(int i = 0; i < providers.size(); i++ ) {
 973             AudioFileReader reader = (AudioFileReader) providers.get(i);
 974             try {
 975                 format = reader.getAudioFileFormat( url ); // throws IOException
 976                 break;
 977             } catch (UnsupportedAudioFileException e) {
 978                 continue;
 979             }
 980         }
 981 
 982         if( format==null ) {
 983             throw new UnsupportedAudioFileException("file is not a supported file type");
 984         } else {
 985             return format;
 986         }
 987     }
 988 
 989     /**
 990      * Obtains the audio file format of the specified {@code File}. The
 991      * {@code File} must point to valid audio file data.
 992      *
 993      * @param  file the {@code File} from which file format information should
 994      *         be extracted
 995      * @return an {@code AudioFileFormat} object describing the audio file
 996      *         format
 997      * @throws UnsupportedAudioFileException if the {@code File} does not point
 998      *         to valid audio file data recognized by the system
 999      * @throws IOException if an I/O exception occurs
1000      */
1001     public static AudioFileFormat getAudioFileFormat(File file)
1002         throws UnsupportedAudioFileException, IOException {
1003 
1004         List providers = getAudioFileReaders();
1005         AudioFileFormat format = null;
1006 
1007         for(int i = 0; i < providers.size(); i++ ) {
1008             AudioFileReader reader = (AudioFileReader) providers.get(i);
1009             try {
1010                 format = reader.getAudioFileFormat( file ); // throws IOException
1011                 break;
1012             } catch (UnsupportedAudioFileException e) {
1013                 continue;
1014             }
1015         }
1016 
1017         if( format==null ) {
1018             throw new UnsupportedAudioFileException("file is not a supported file type");
1019         } else {
1020             return format;
1021         }
1022     }
1023 
1024     /**
1025      * Obtains an audio input stream from the provided input stream. The stream
1026      * must point to valid audio file data. The implementation of this method
1027      * may require multiple parsers to examine the stream to determine whether
1028      * they support it. These parsers must be able to mark the stream, read
1029      * enough data to determine whether they support the stream, and, if not,
1030      * reset the stream's read pointer to its original position. If the input
1031      * stream does not support these operation, this method may fail with an
1032      * {@code IOException}.
1033      *
1034      * @param  stream the input stream from which the {@code AudioInputStream}
1035      *         should be constructed
1036      * @return an {@code AudioInputStream} object based on the audio file data
1037      *         contained in the input stream
1038      * @throws UnsupportedAudioFileException if the stream does not point to
1039      *         valid audio file data recognized by the system
1040      * @throws IOException if an I/O exception occurs
1041      * @see InputStream#markSupported
1042      * @see InputStream#mark
1043      */
1044     public static AudioInputStream getAudioInputStream(InputStream stream)
1045         throws UnsupportedAudioFileException, IOException {
1046 
1047         List providers = getAudioFileReaders();
1048         AudioInputStream audioStream = null;
1049 
1050         for(int i = 0; i < providers.size(); i++ ) {
1051             AudioFileReader reader = (AudioFileReader) providers.get(i);
1052             try {
1053                 audioStream = reader.getAudioInputStream( stream ); // throws IOException
1054                 break;
1055             } catch (UnsupportedAudioFileException e) {
1056                 continue;
1057             }
1058         }
1059 
1060         if( audioStream==null ) {
1061             throw new UnsupportedAudioFileException("could not get audio input stream from input stream");
1062         } else {
1063             return audioStream;
1064         }
1065     }
1066 
1067     /**
1068      * Obtains an audio input stream from the URL provided. The URL must point
1069      * to valid audio file data.
1070      *
1071      * @param  url the URL for which the {@code AudioInputStream} should be
1072      *         constructed
1073      * @return an {@code AudioInputStream} object based on the audio file data
1074      *         pointed to by the URL
1075      * @throws UnsupportedAudioFileException if the URL does not point to valid
1076      *         audio file data recognized by the system
1077      * @throws IOException if an I/O exception occurs
1078      */
1079     public static AudioInputStream getAudioInputStream(URL url)
1080         throws UnsupportedAudioFileException, IOException {
1081 
1082         List providers = getAudioFileReaders();
1083         AudioInputStream audioStream = null;
1084 
1085         for(int i = 0; i < providers.size(); i++ ) {
1086             AudioFileReader reader = (AudioFileReader) providers.get(i);
1087             try {
1088                 audioStream = reader.getAudioInputStream( url ); // throws IOException
1089                 break;
1090             } catch (UnsupportedAudioFileException e) {
1091                 continue;
1092             }
1093         }
1094 
1095         if( audioStream==null ) {
1096             throw new UnsupportedAudioFileException("could not get audio input stream from input URL");
1097         } else {
1098             return audioStream;
1099         }
1100     }
1101 
1102     /**
1103      * Obtains an audio input stream from the provided {@code File}. The
1104      * {@code File} must point to valid audio file data.
1105      *
1106      * @param  file the {@code File} for which the {@code AudioInputStream}
1107      *         should be constructed
1108      * @return an {@code AudioInputStream} object based on the audio file data
1109      *         pointed to by the {@code File}
1110      * @throws UnsupportedAudioFileException if the {@code File} does not point
1111      *         to valid audio file data recognized by the system
1112      * @throws IOException if an I/O exception occurs
1113      */
1114     public static AudioInputStream getAudioInputStream(File file)
1115         throws UnsupportedAudioFileException, IOException {
1116 
1117         List providers = getAudioFileReaders();
1118         AudioInputStream audioStream = null;
1119 
1120         for(int i = 0; i < providers.size(); i++ ) {
1121             AudioFileReader reader = (AudioFileReader) providers.get(i);
1122             try {
1123                 audioStream = reader.getAudioInputStream( file ); // throws IOException
1124                 break;
1125             } catch (UnsupportedAudioFileException e) {
1126                 continue;
1127             }
1128         }
1129 
1130         if( audioStream==null ) {
1131             throw new UnsupportedAudioFileException("could not get audio input stream from input file");
1132         } else {
1133             return audioStream;
1134         }
1135     }
1136 
1137     /**
1138      * Obtains the file types for which file writing support is provided by the
1139      * system.
1140      *
1141      * @return array of unique file types. If no file types are supported, an
1142      *         array of length 0 is returned.
1143      */
1144     public static AudioFileFormat.Type[] getAudioFileTypes() {
1145         List providers = getAudioFileWriters();
1146         Set returnTypesSet = new HashSet();
1147 
1148         for(int i=0; i < providers.size(); i++) {
1149             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1150             AudioFileFormat.Type[] fileTypes = writer.getAudioFileTypes();
1151             for(int j=0; j < fileTypes.length; j++) {
1152                 returnTypesSet.add(fileTypes[j]);
1153             }
1154         }
1155         AudioFileFormat.Type returnTypes[] = (AudioFileFormat.Type[])
1156             returnTypesSet.toArray(new AudioFileFormat.Type[0]);
1157         return returnTypes;
1158     }
1159 
1160     /**
1161      * Indicates whether file writing support for the specified file type is
1162      * provided by the system.
1163      *
1164      * @param  fileType the file type for which write capabilities are queried
1165      * @return {@code true} if the file type is supported, otherwise
1166      *         {@code false}
1167      */
1168     public static boolean isFileTypeSupported(AudioFileFormat.Type fileType) {
1169 
1170         List providers = getAudioFileWriters();
1171 
1172         for(int i=0; i < providers.size(); i++) {
1173             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1174             if (writer.isFileTypeSupported(fileType)) {
1175                 return true;
1176             }
1177         }
1178         return false;
1179     }
1180 
1181     /**
1182      * Obtains the file types that the system can write from the audio input
1183      * stream specified.
1184      *
1185      * @param  stream the audio input stream for which audio file type
1186      *         support is queried
1187      * @return array of file types. If no file types are supported, an array of
1188      *         length 0 is returned.
1189      */
1190     public static AudioFileFormat.Type[] getAudioFileTypes(AudioInputStream stream) {
1191         List providers = getAudioFileWriters();
1192         Set returnTypesSet = new HashSet();
1193 
1194         for(int i=0; i < providers.size(); i++) {
1195             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1196             AudioFileFormat.Type[] fileTypes = writer.getAudioFileTypes(stream);
1197             for(int j=0; j < fileTypes.length; j++) {
1198                 returnTypesSet.add(fileTypes[j]);
1199             }
1200         }
1201         AudioFileFormat.Type returnTypes[] = (AudioFileFormat.Type[])
1202             returnTypesSet.toArray(new AudioFileFormat.Type[0]);
1203         return returnTypes;
1204     }
1205 
1206     /**
1207      * Indicates whether an audio file of the specified file type can be written
1208      * from the indicated audio input stream.
1209      *
1210      * @param  fileType the file type for which write capabilities are queried
1211      * @param  stream the stream for which file-writing support is queried
1212      * @return {@code true} if the file type is supported for this audio input
1213      *         stream, otherwise {@code false}
1214      */
1215     public static boolean isFileTypeSupported(AudioFileFormat.Type fileType,
1216                                               AudioInputStream stream) {
1217 
1218         List providers = getAudioFileWriters();
1219 
1220         for(int i=0; i < providers.size(); i++) {
1221             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1222             if(writer.isFileTypeSupported(fileType, stream)) {
1223                 return true;
1224             }
1225         }
1226         return false;
1227     }
1228 
1229     /**
1230      * Writes a stream of bytes representing an audio file of the specified file
1231      * type to the output stream provided. Some file types require that the
1232      * length be written into the file header; such files cannot be written from
1233      * start to finish unless the length is known in advance. An attempt to
1234      * write a file of such a type will fail with an IOException if the length
1235      * in the audio file type is {@code AudioSystem.NOT_SPECIFIED}.
1236      *
1237      * @param  stream the audio input stream containing audio data to be written
1238      *         to the file
1239      * @param  fileType the kind of audio file to write
1240      * @param  out the stream to which the file data should be written
1241      * @return the number of bytes written to the output stream
1242      * @throws IOException if an input/output exception occurs
1243      * @throws IllegalArgumentException if the file type is not supported by the
1244      *         system
1245      * @see #isFileTypeSupported
1246      * @see #getAudioFileTypes
1247      */
1248     public static int write(AudioInputStream stream, AudioFileFormat.Type fileType,
1249                             OutputStream out) throws IOException {
1250 
1251         List providers = getAudioFileWriters();
1252         int bytesWritten = 0;
1253         boolean flag = false;
1254 
1255         for(int i=0; i < providers.size(); i++) {
1256             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1257             try {
1258                 bytesWritten = writer.write( stream, fileType, out ); // throws IOException
1259                 flag = true;
1260                 break;
1261             } catch (IllegalArgumentException e) {
1262                 // thrown if this provider cannot write the sequence, try the next
1263                 continue;
1264             }
1265         }
1266         if(!flag) {
1267             throw new IllegalArgumentException("could not write audio file: file type not supported: " + fileType);
1268         } else {
1269             return bytesWritten;
1270         }
1271     }
1272 
1273     /**
1274      * Writes a stream of bytes representing an audio file of the specified file
1275      * type to the external file provided.
1276      *
1277      * @param  stream the audio input stream containing audio data to be written
1278      *         to the file
1279      * @param  fileType the kind of audio file to write
1280      * @param  out the external file to which the file data should be written
1281      * @return the number of bytes written to the file
1282      * @throws IOException if an I/O exception occurs
1283      * @throws IllegalArgumentException if the file type is not supported by the
1284      *         system
1285      * @see #isFileTypeSupported
1286      * @see #getAudioFileTypes
1287      */
1288     public static int write(AudioInputStream stream, AudioFileFormat.Type fileType,
1289                             File out) throws IOException {
1290 
1291         List providers = getAudioFileWriters();
1292         int bytesWritten = 0;
1293         boolean flag = false;
1294 
1295         for(int i=0; i < providers.size(); i++) {
1296             AudioFileWriter writer = (AudioFileWriter) providers.get(i);
1297             try {
1298                 bytesWritten = writer.write( stream, fileType, out ); // throws IOException
1299                 flag = true;
1300                 break;
1301             } catch (IllegalArgumentException e) {
1302                 // thrown if this provider cannot write the sequence, try the next
1303                 continue;
1304             }
1305         }
1306         if (!flag) {
1307             throw new IllegalArgumentException("could not write audio file: file type not supported: " + fileType);
1308         } else {
1309             return bytesWritten;
1310         }
1311     }
1312 
1313     // METHODS FOR INTERNAL IMPLEMENTATION USE
1314 
1315     /**
1316      * Obtains the set of MixerProviders on the system.
1317      */
1318     private static List getMixerProviders() {
1319         return getProviders(MixerProvider.class);
1320     }
1321 
1322     /**
1323      * Obtains the set of format converters (codecs, transcoders, etc.) that are
1324      * currently installed on the system.
1325      *
1326      * @return an array of {@link javax.sound.sampled.spi.FormatConversionProvider
1327      *         FormatConversionProvider} objects representing the available
1328      *         format converters. If no format converters readers are available
1329      *         on the system, an array of length 0 is returned.
1330      */
1331     private static List getFormatConversionProviders() {
1332         return getProviders(FormatConversionProvider.class);
1333     }
1334 
1335     /**
1336      * Obtains the set of audio file readers that are currently installed on the
1337      * system.
1338      *
1339      * @return a List of {@link javax.sound.sampled.spi.AudioFileReader
1340      *         AudioFileReader} objects representing the installed audio file
1341      *         readers. If no audio file readers are available on the system, an
1342      *         empty List is returned.
1343      */
1344     private static List getAudioFileReaders() {
1345         return getProviders(AudioFileReader.class);
1346     }
1347 
1348     /**
1349      * Obtains the set of audio file writers that are currently installed on the
1350      * system.
1351      *
1352      * @return a List of {@link javax.sound.sampled.spi.AudioFileWriter
1353      *         AudioFileWriter} objects representing the available audio file
1354      *         writers. If no audio file writers are available on the system, an
1355      *         empty List is returned.
1356      */
1357     private static List getAudioFileWriters() {
1358         return getProviders(AudioFileWriter.class);
1359     }
1360 
1361     /**
1362      * Attempts to locate and return a default Mixer that provides lines of the
1363      * specified type.
1364      *
1365      * @param  providers the installed mixer providers
1366      * @param  info The requested line type TargetDataLine.class, Clip.class or
1367      *         Port.class
1368      * @return a Mixer that matches the requirements, or null if no default
1369      *         mixer found
1370      */
1371     private static Mixer getDefaultMixer(List providers, Line.Info info) {
1372         Class lineClass = info.getLineClass();
1373         String providerClassName = JDK13Services.getDefaultProviderClassName(lineClass);
1374         String instanceName = JDK13Services.getDefaultInstanceName(lineClass);
1375         Mixer mixer;
1376 
1377         if (providerClassName != null) {
1378             MixerProvider defaultProvider = getNamedProvider(providerClassName, providers);
1379             if (defaultProvider != null) {
1380                 if (instanceName != null) {
1381                     mixer = getNamedMixer(instanceName, defaultProvider, info);
1382                     if (mixer != null) {
1383                         return mixer;
1384                     }
1385                 } else {
1386                     mixer = getFirstMixer(defaultProvider, info,
1387                                           false /* mixing not required*/);
1388                     if (mixer != null) {
1389                         return mixer;
1390                     }
1391                 }
1392 
1393             }
1394         }
1395 
1396         /* Provider class not specified or
1397            provider class cannot be found, or
1398            provider class and instance specified and instance cannot be found or is not appropriate */
1399         if (instanceName != null) {
1400             mixer = getNamedMixer(instanceName, providers, info);
1401             if (mixer != null) {
1402                 return mixer;
1403             }
1404         }
1405 
1406 
1407         /* No default are specified, or if something is specified, everything
1408            failed. */
1409         return null;
1410     }
1411 
1412     /**
1413      * Return a MixerProvider of a given class from the list of MixerProviders.
1414      * This method never requires the returned Mixer to do mixing.
1415      *
1416      * @param  providerClassName The class name of the provider to be returned
1417      * @param  providers The list of MixerProviders that is searched
1418      * @return A MixerProvider of the requested class, or null if none is found
1419      */
1420     private static MixerProvider getNamedProvider(String providerClassName,
1421                                                   List providers) {
1422         for(int i = 0; i < providers.size(); i++) {
1423             MixerProvider provider = (MixerProvider) providers.get(i);
1424             if (provider.getClass().getName().equals(providerClassName)) {
1425                 return provider;
1426             }
1427         }
1428         return null;
1429     }
1430 
1431     /**
1432      * Return a Mixer with a given name from a given MixerProvider. This method
1433      * never requires the returned Mixer to do mixing.
1434      *
1435      * @param  mixerName The name of the Mixer to be returned
1436      * @param  provider The MixerProvider to check for Mixers
1437      * @param  info The type of line the returned Mixer is required to support
1438      * @return A Mixer matching the requirements, or null if none is found
1439      */
1440     private static Mixer getNamedMixer(String mixerName,
1441                                        MixerProvider provider,
1442                                        Line.Info info) {
1443         Mixer.Info[] infos = provider.getMixerInfo();
1444         for (int i = 0; i < infos.length; i++) {
1445             if (infos[i].getName().equals(mixerName)) {
1446                 Mixer mixer = provider.getMixer(infos[i]);
1447                 if (isAppropriateMixer(mixer, info, false)) {
1448                     return mixer;
1449                 }
1450             }
1451         }
1452         return null;
1453     }
1454 
1455     /**
1456      * From a List of MixerProviders, return a Mixer with a given name. This
1457      * method never requires the returned Mixer to do mixing.
1458      *
1459      * @param  mixerName The name of the Mixer to be returned
1460      * @param  providers The List of MixerProviders to check for Mixers
1461      * @param  info The type of line the returned Mixer is required to support
1462      * @return A Mixer matching the requirements, or null if none is found
1463      */
1464     private static Mixer getNamedMixer(String mixerName,
1465                                        List providers,
1466                                        Line.Info info) {
1467         for(int i = 0; i < providers.size(); i++) {
1468             MixerProvider provider = (MixerProvider) providers.get(i);
1469             Mixer mixer = getNamedMixer(mixerName, provider, info);
1470             if (mixer != null) {
1471                 return mixer;
1472             }
1473         }
1474         return null;
1475     }
1476 
1477     /**
1478      * From a given MixerProvider, return the first appropriate Mixer.
1479      *
1480      * @param  provider The MixerProvider to check for Mixers
1481      * @param  info The type of line the returned Mixer is required to support
1482      * @param  isMixingRequired If true, only Mixers that support mixing are
1483      *         returned for line types of SourceDataLine and Clip
1484      * @return A Mixer that is considered appropriate, or null if none is found
1485      */
1486     private static Mixer getFirstMixer(MixerProvider provider,
1487                                        Line.Info info,
1488                                        boolean isMixingRequired) {
1489         Mixer.Info[] infos = provider.getMixerInfo();
1490         for (int j = 0; j < infos.length; j++) {
1491             Mixer mixer = provider.getMixer(infos[j]);
1492             if (isAppropriateMixer(mixer, info, isMixingRequired)) {
1493                 return mixer;
1494             }
1495         }
1496         return null;
1497     }
1498 
1499     /**
1500      * Checks if a Mixer is appropriate. A Mixer is considered appropriate if it
1501      * support the given line type. If isMixingRequired is true and the line
1502      * type is an output one (SourceDataLine, Clip), the mixer is appropriate if
1503      * it supports at least 2 (concurrent) lines of the given type.
1504      *
1505      * @return {@code true} if the mixer is considered appropriate according to
1506      *         the rules given above, {@code false} otherwise
1507      */
1508     private static boolean isAppropriateMixer(Mixer mixer,
1509                                               Line.Info lineInfo,
1510                                               boolean isMixingRequired) {
1511         if (! mixer.isLineSupported(lineInfo)) {
1512             return false;
1513         }
1514         Class lineClass = lineInfo.getLineClass();
1515         if (isMixingRequired
1516             && (SourceDataLine.class.isAssignableFrom(lineClass) ||
1517                 Clip.class.isAssignableFrom(lineClass))) {
1518             int maxLines = mixer.getMaxLines(lineInfo);
1519             return ((maxLines == NOT_SPECIFIED) || (maxLines > 1));
1520         }
1521         return true;
1522     }
1523 
1524     /**
1525      * Like getMixerInfo, but return List.
1526      */
1527     private static List getMixerInfoList() {
1528         List providers = getMixerProviders();
1529         return getMixerInfoList(providers);
1530     }
1531 
1532     /**
1533      * Like getMixerInfo, but return List.
1534      */
1535     private static List getMixerInfoList(List providers) {
1536         List infos = new ArrayList();
1537 
1538         Mixer.Info[] someInfos; // per-mixer
1539         Mixer.Info[] allInfos;  // for all mixers
1540 
1541         for(int i = 0; i < providers.size(); i++ ) {
1542             someInfos = ((MixerProvider)providers.get(i)).getMixerInfo();
1543 
1544             for (int j = 0; j < someInfos.length; j++) {
1545                 infos.add(someInfos[j]);
1546             }
1547         }
1548 
1549         return infos;
1550     }
1551 
1552     /**
1553      * Obtains the set of services currently installed on the system using the
1554      * SPI mechanism in 1.3.
1555      *
1556      * @return a List of instances of providers for the requested service. If no
1557      *         providers are available, a vector of length 0 will be returned.
1558      */
1559     private static List getProviders(Class providerClass) {
1560         return JDK13Services.getProviders(providerClass);
1561     }
1562 }