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 sun.audio;

    27 

    28 import java.io.InputStream;

    29 import java.security.AccessController;

    30 import java.security.PrivilegedAction;

    31 

    32 

    33 /**

    34  * This class provides an interface to play audio streams.

    35  *

    36  * To play an audio stream use:

    37  * <pre>

    38  *      AudioPlayer.player.start(audiostream);

    39  * </pre>

    40  * To stop playing an audio stream use:

    41  * <pre>

    42  *      AudioPlayer.player.stop(audiostream);

    43  * </pre>

    44  * To play an audio stream from a URL use:

    45  * <pre>

    46  *      AudioStream audiostream = new AudioStream(url.openStream());

    47  *      AudioPlayer.player.start(audiostream);

    48  * </pre>

    49  * To play a continuous sound you first have to

    50  * create an AudioData instance and use it to construct a

    51  * ContinuousAudioDataStream.

    52  * For example:

    53  * <pre>

    54  *      AudioData data = new AudioStream(url.openStream()).getData();

    55  *      ContinuousAudioDataStream audiostream = new ContinuousAudioDataStream(data);

    56  *      AudioPlayer.player.start(audiostream);

    57  * </pre>

    58  *

    59  * @see AudioData

    60  * @see AudioDataStream

    61  * @see AudioDevice

    62  * @see AudioStream

    63  * @author Arthur van Hoff, Thomas Ball

    64  */

    65 

    66 public final class AudioPlayer extends Thread {

    67 

    68         private final AudioDevice devAudio;

    69         private final static boolean DEBUG = false /*true*/;

    70 

    71         /**

    72          * The default audio player. This audio player is initialized

    73          * automatically.

    74          */

    75         public static final AudioPlayer player = getAudioPlayer();

    76 

    77         private static ThreadGroup getAudioThreadGroup() {

    78 

    79             if(DEBUG) { System.out.println("AudioPlayer.getAudioThreadGroup()"); }

    80             ThreadGroup g = currentThread().getThreadGroup();

    81             while ((g.getParent() != null) &&

    82                    (g.getParent().getParent() != null)) {

    83                 g = g.getParent();

    84             }

    85             return g;

    86         }

    87 

    88         /**

    89          * Create an AudioPlayer thread in a privileged block.

    90          */

    91 

    92         private static AudioPlayer getAudioPlayer() {

    93 

    94             if(DEBUG) { System.out.println("> AudioPlayer.getAudioPlayer()"); }

    95             PrivilegedAction<AudioPlayer> action = new PrivilegedAction<AudioPlayer>() {

    96                     public AudioPlayer run() {

    97                         AudioPlayer t = new AudioPlayer();

    98                         t.setPriority(MAX_PRIORITY);

    99                         t.setDaemon(true);

   100                         t.start();

   101                         return t;

   102                     }

   103                 };

   104             return  AccessController.doPrivileged(action);

   105         }

   106 

   107         /**

   108          * Construct an AudioPlayer.

   109          */

   110         private AudioPlayer() {

   111 

   112             super(getAudioThreadGroup(), "Audio Player");

   113             if(DEBUG) { System.out.println("> AudioPlayer private constructor"); }

   114             devAudio = AudioDevice.device;

   115             devAudio.open();

   116             if(DEBUG) { System.out.println("< AudioPlayer private constructor completed"); }

   117         }

   118 

   119 

   120         /**

   121          * Start playing a stream. The stream will continue to play

   122          * until the stream runs out of data, or it is stopped.

   123          * @see AudioPlayer#stop

   124          */

   125         public synchronized void start(InputStream in) {

   126 

   127             if(DEBUG) {

   128                 System.out.println("> AudioPlayer.start");

   129                 System.out.println("  InputStream = " + in);

   130             }

   131             devAudio.openChannel(in);

   132             notify();

   133             if(DEBUG) {

   134                 System.out.println("< AudioPlayer.start completed");

   135             }

   136         }

   137 

   138         /**

   139          * Stop playing a stream. The stream will stop playing,

   140          * nothing happens if the stream wasn't playing in the

   141          * first place.

   142          * @see AudioPlayer#start

   143          */

   144         public synchronized void stop(InputStream in) {

   145 

   146             if(DEBUG) {

   147                 System.out.println("> AudioPlayer.stop");

   148             }

   149 

   150             devAudio.closeChannel(in);

   151             if(DEBUG) {

   152                 System.out.println("< AudioPlayer.stop completed");

   153             }

   154         }

   155 

   156         /**

   157          * Main mixing loop. This is called automatically when the AudioPlayer

   158          * is created.

   159          */

   160         public void run() {

   161 

   162             // $$jb: 06.24.99: With the JS API, mixing is no longer done by AudioPlayer

   163             // or AudioDevice ... it's done by the API itself, so this bit of legacy

   164             // code does nothing.

   165             // $$jb: 10.21.99: But it appears that some legacy applications

   166             // check to see if this thread is alive or not, so we need to spin here.

   167 

   168             devAudio.play();

   169             if(DEBUG) {

   170                 System.out.println("AudioPlayer mixing loop.");

   171             }

   172             while(true) {

   173                 try{

   174                     Thread.sleep(5000);

   175                     //wait();

   176                 } catch(Exception e) {

   177                     break;

   178                     // interrupted

   179                 }

   180             }

   181             if(DEBUG) {

   182                 System.out.println("AudioPlayer exited.");

   183             }

   184 

   185         }

   186     }