Robust/src/Tests/ssJava/mp3decoder/Player.java

   1 /*\r
   2  * 11/19/04             1.0 moved to LGPL.\r
   3  * 29/01/00             Initial version. mdm@techie.com\r
   4  *-----------------------------------------------------------------------\r
   5  *   This program is free software; you can redistribute it and/or modify\r
   6  *   it under the terms of the GNU Library General Public License as published\r
   7  *   by the Free Software Foundation; either version 2 of the License, or\r
   8  *   (at your option) any later version.\r
   9  *\r
  10  *   This program is distributed in the hope that it will be useful,\r
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of\r
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
  13  *   GNU Library General Public License for more details.\r
  14  *\r
  15  *   You should have received a copy of the GNU Library General Public\r
  16  *   License along with this program; if not, write to the Free Software\r
  17  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.\r
  18  *----------------------------------------------------------------------\r
  19  */\r
  20 \r
  21 package javazoom.jl.player;\r
  22 \r
  23 import java.io.InputStream;\r
  24 \r
  25 import javazoom.jl.decoder.Bitstream;\r
  26 import javazoom.jl.decoder.BitstreamException;\r
  27 import javazoom.jl.decoder.Decoder;\r
  28 import javazoom.jl.decoder.Header;\r
  29 import javazoom.jl.decoder.JavaLayerException;\r
  30 import javazoom.jl.decoder.SampleBuffer;\r
  31         \r
  32 /**\r
  33  * The <code>Player</code> class implements a simple player for playback\r
  34  * of an MPEG audio stream. \r
  35  * \r
  36  * @author      Mat McGowan\r
  37  * @since       0.0.8\r
  38  */\r
  39 \r
  40 // REVIEW: the audio device should not be opened until the\r
  41 // first MPEG audio frame has been decoded. \r
  42 public class Player\r
  43 {               \r
  44         /**\r
  45          * The current frame number. \r
  46          */\r
  47         private int frame = 0;\r
  48         \r
  49         /**\r
  50          * The MPEG audio bitstream. \r
  51          */\r
  52         // javac blank final bug. \r
  53         /*final*/ private Bitstream             bitstream;\r
  54         \r
  55         /**\r
  56          * The MPEG audio decoder. \r
  57          */\r
  58         /*final*/ private Decoder               decoder; \r
  59         \r
  60         /**\r
  61          * The AudioDevice the audio samples are written to. \r
  62          */\r
  63         private AudioDevice     audio;\r
  64         \r
  65         /**\r
  66          * Has the player been closed?\r
  67          */\r
  68         private boolean         closed = false;\r
  69         \r
  70         /**\r
  71          * Has the player played back all frames from the stream?\r
  72          */\r
  73         private boolean         complete = false;\r
  74 \r
  75         private int                     lastPosition = 0;\r
  76         \r
  77         /**\r
  78          * Creates a new <code>Player</code> instance. \r
  79          */\r
  80         public Player(InputStream stream) throws JavaLayerException\r
  81         {\r
  82                 this(stream, null);     \r
  83         }\r
  84         \r
  85         public Player(InputStream stream, AudioDevice device) throws JavaLayerException\r
  86         {\r
  87                 bitstream = new Bitstream(stream);              \r
  88                 decoder = new Decoder();\r
  89                                 \r
  90                 if (device!=null)\r
  91                 {               \r
  92                         audio = device;\r
  93                 }\r
  94                 else\r
  95                 {                       \r
  96                         FactoryRegistry r = FactoryRegistry.systemRegistry();\r
  97                         audio = r.createAudioDevice();\r
  98                 }\r
  99                 audio.open(decoder);\r
 100         }\r
 101         \r
 102         public void play() throws JavaLayerException\r
 103         {\r
 104                 play(Integer.MAX_VALUE);\r
 105         }\r
 106         \r
 107         /**\r
 108          * Plays a number of MPEG audio frames. \r
 109          * \r
 110          * @param frames        The number of frames to play. \r
 111          * @return      true if the last frame was played, or false if there are\r
 112          *                      more frames. \r
 113          */\r
 114         public boolean play(int frames) throws JavaLayerException\r
 115         {\r
 116                 boolean ret = true;\r
 117                         \r
 118                 while (frames-- > 0 && ret)\r
 119                 {\r
 120                         ret = decodeFrame();                    \r
 121                 }\r
 122                 \r
 123                 if (!ret)\r
 124                 {\r
 125                         // last frame, ensure all data flushed to the audio device. \r
 126                         AudioDevice out = audio;\r
 127                         if (out!=null)\r
 128                         {                               \r
 129                                 out.flush();\r
 130                                 synchronized (this)\r
 131                                 {\r
 132                                         complete = (!closed);\r
 133                                         close();\r
 134                                 }                               \r
 135                         }\r
 136                 }\r
 137                 return ret;\r
 138         }\r
 139                 \r
 140         /**\r
 141          * Cloases this player. Any audio currently playing is stopped\r
 142          * immediately. \r
 143          */\r
 144         public synchronized void close()\r
 145         {               \r
 146                 AudioDevice out = audio;\r
 147                 if (out!=null)\r
 148                 { \r
 149                         closed = true;\r
 150                         audio = null;   \r
 151                         // this may fail, so ensure object state is set up before\r
 152                         // calling this method. \r
 153                         out.close();\r
 154                         lastPosition = out.getPosition();\r
 155                         try\r
 156                         {\r
 157                                 bitstream.close();\r
 158                         }\r
 159                         catch (BitstreamException ex)\r
 160                         {\r
 161                         }\r
 162                 }\r
 163         }\r
 164         \r
 165         /**\r
 166          * Returns the completed status of this player.\r
 167          * \r
 168          * @return      true if all available MPEG audio frames have been\r
 169          *                      decoded, or false otherwise. \r
 170          */\r
 171         public synchronized boolean isComplete()\r
 172         {\r
 173                 return complete;        \r
 174         }\r
 175                                 \r
 176         /**\r
 177          * Retrieves the position in milliseconds of the current audio\r
 178          * sample being played. This method delegates to the <code>\r
 179          * AudioDevice</code> that is used by this player to sound\r
 180          * the decoded audio samples. \r
 181          */\r
 182         public int getPosition()\r
 183         {\r
 184                 int position = lastPosition;\r
 185                 \r
 186                 AudioDevice out = audio;                \r
 187                 if (out!=null)\r
 188                 {\r
 189                         position = out.getPosition();   \r
 190                 }\r
 191                 return position;\r
 192         }               \r
 193         \r
 194         /**\r
 195          * Decodes a single frame.\r
 196          * \r
 197          * @return true if there are no more frames to decode, false otherwise.\r
 198          */\r
 199         protected boolean decodeFrame() throws JavaLayerException\r
 200         {               \r
 201                 try\r
 202                 {\r
 203                         AudioDevice out = audio;\r
 204                         if (out==null)\r
 205                                 return false;\r
 206 \r
 207                         Header h = bitstream.readFrame();       \r
 208                         \r
 209                         if (h==null)\r
 210                                 return false;\r
 211                                 \r
 212                         // sample buffer set when decoder constructed\r
 213                         SampleBuffer output = (SampleBuffer)decoder.decodeFrame(h, bitstream);\r
 214                                                                                                                                                                                                                                                                                                         \r
 215                         synchronized (this)\r
 216                         {\r
 217                                 out = audio;\r
 218                                 if (out!=null)\r
 219                                 {                                       \r
 220                                         out.write(output.getBuffer(), 0, output.getBufferLength());\r
 221                                 }                               \r
 222                         }\r
 223                                                                                                                                                         \r
 224                         bitstream.closeFrame();\r
 225                 }               \r
 226                 catch (RuntimeException ex)\r
 227                 {\r
 228                         throw new JavaLayerException("Exception decoding audio frame", ex);\r
 229                 }\r
 230 /*\r
 231                 catch (IOException ex)\r
 232                 {\r
 233                         System.out.println("exception decoding audio frame: "+ex);\r
 234                         return false;   \r
 235                 }\r
 236                 catch (BitstreamException bitex)\r
 237                 {\r
 238                         System.out.println("exception decoding audio frame: "+bitex);\r
 239                         return false;   \r
 240                 }\r
 241                 catch (DecoderException decex)\r
 242                 {\r
 243                         System.out.println("exception decoding audio frame: "+decex);\r
 244                         return false;                           \r
 245                 }\r
 246 */              \r
 247                 return true;\r
 248         }\r
 249 \r
 250         \r
 251 }\r