一个异常问题

fishhing 2009-11-16 02:13:21

Exception in thread "Thread-10" java.lang.IllegalStateException: sequencer not open
at com.sun.media.sound.RealTimeSequencer.start(Unknown Source)
at javax.microedition.media.PlayerImpl.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
请问一下，这个异常是因为什么原因，这个是由于调整背景音乐的音量产生的

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fishhing 2009-11-16

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原因好像是因为，Player对象处于STARTED状态，然后调用了stop()方法后，再调用start()方法就出现了异常Exception in thread "Thread-16" java.lang.IllegalStateException: sequencer not open
at com.sun.media.sound.RealTimeSequencer.start(Unknown Source)
at javax.microedition.media.PlayerImpl.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

fishhing 2009-11-16

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上面的问题说错了，不是第一次调用那3个语句出错，而是当背景音乐在开启状态时第一次执行gameMusic.stopMusic();
gameMusic.volume(MUSIC_VOLUME[optionData]);
gameMusic.startMusic();
时出错，然后再执行时没关系

fishhing 2009-11-16

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先执行了这个方法
void startMusic(int pos) {
try{
if (optionData > 0) {
if (gameMusic != null) {
gameMusic.deallocate();
gameMusic = null;
}
String currentMusic = null;
switch (pos) {
case 1 :
currentMusic = currentBgMusic;
break;
case 2 :
if (gameFight.isEscape) {
currentMusic = "/ft.mid";
} else {
currentMusic = "/ft1.mid";
}
break;
}
gameMusic = new Music(currentMusic, -1);
gameMusic.volume(MUSIC_VOLUME[optionData]);
gameMusic.startMusic();
}
}catch(Exception e){
System.out.println("startMusic Exception");
}

}

然后第一次调用这3句话的时候出错，然后调用的时候就没事了
gameMusic.stopMusic();
gameMusic.volume(MUSIC_VOLUME[optionData]);
gameMusic.startMusic();

gameMusic是Music 类的实例

public class Music {
public Player sound;

public Music(String FileName, int loop) {
try {
sound = Manager.createPlayer("0".getClass().getResourceAsStream(FileName), "audio/midi");
sound.realize();
sound.setLoopCount(loop); //-1 为循环播放
sound.prefetch();
} catch (Exception e) {
System.out.println("Music Exception ");
}
}

public void startMusic() {
try {
sound.start();
} catch (Exception e) {
System.out.println("startMusic");
}
}

public void stopMusic() {
try {
if (sound.getState() == Player.STARTED){
sound.stop();
}
sound.setMediaTime(0);
System.out.println("sound.prefetched="+sound.PREFETCHED);
System.out.println("sound.getState()="+sound.getState());
} catch (MediaException e) {
System.out.println("MediaException");
}catch(Exception e){
System.out.println("Exception");
}
}

public void volume(int iMusicLevel) {
try{
VolumeControl volume = (VolumeControl) sound.getControl("VolumeControl");
volume.setLevel(iMusicLevel);
}catch(Exception e){
System.out.println("volume Exception");
}

}

public void deallocate() {
try {
if (sound.getState() == Player.STARTED)
sound.stop();
sound.deallocate();
sound.close();
sound = null;
} catch (Exception e) {
System.out.println("deallocate Exception");
e.printStackTrace();
}
}

}