不能與JMF

Question

播放mp3流我有一些像這樣的短音頻播放器示例代碼運行正常：

public class AudioTest { 

    public static void main(String[] args) { 
     Format input1 = new AudioFormat(AudioFormat.MPEGLAYER3); 
     Format input2 = new AudioFormat(AudioFormat.MPEG); 
     Format output = new AudioFormat(AudioFormat.LINEAR); 
     PlugInManager.addPlugIn(
       "com.sun.media.codec.audio.mp3.JavaDecoder", 
       new Format[]{input1, input2}, 
       new Format[]{output}, 
       PlugInManager.CODEC); 
     try { 
      Player player = Manager.createPlayer(new File("tone.mp3").toURL()); 
      player.start(); 
     } catch (Exception ex) { 
      ex.printStackTrace(); 
     } 
    } 
} 

現在，我想從一個servlet與流的MP3：

Manager.createPlayer(new URL("http://localhost:88/media/tone.mp3")); 

的servlet收到請求後打開一個測試文件併發送給請求者。問題是mp3沒有播放（沒有聲音），也沒有任何錯誤信息。

如果我通過瀏覽器下載文件，文件播放正確。

該servlet是這樣的：

public class MediaSource extends HttpServlet { 

    @Override 
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 

     System.err.println(req); 

     File mp3 = new File("tone.mp3"); 
     InputStream in = new FileInputStream(mp3); 

     resp.setContentType("audio/mpeg"); 
     resp.addHeader("Content-Disposition", 
       "attachment; filename=" + mp3.getName()); 

     resp.setContentLength((int) mp3.length()); 

     ServletOutputStream out = resp.getOutputStream(); 
     byte buf[] = new byte[1024]; 
     int n = in.read(buf, 0, 1024); 
     while (n > 0) { 
      out.write(buf, 0, n); 
      out.flush(); 
      n = in.read(buf, 0, 1024); 
     } 

     in.close(); 
     out.close(); 
    } 
} 

更新爲@jogabonito

這是

javax.media.TransitionEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Unrealized,current=Realizing,target=Started] 
javax.media.CachingControlEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,cachingControl=com.sun.media.protocol.DataSource$CachingControl@f9f9d8,progress=102400] 
javax.media.DurationUpdateEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,duration=javax.media.Time@1decdec 
javax.media.RealizeCompleteEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Realizing,current=Realized,target=Started] 
javax.media.TransitionEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Realized,current=Prefetching,target=Started] 
javax.media.CachingControlEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,cachingControl=com.sun.media.protocol.DataSource$CachingControl@f9f9d8,progress=204800] 
javax.media.CachingControlEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,cachingControl=com.sun.media.protocol.DataSource$CachingControl@f9f9d8,progress=205889] 
javax.media.PrefetchCompleteEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Prefetching,current=Prefetched,target=Started] 
javax.media.StartEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Prefetched,current=Started,target=Started,mediaTime=javax.media.Time@691f36,timeBaseTime=javax.media.Time@18020cc] 
javax.media.EndOfMediaEvent[source=com.sun.media.content.unknown.Handler@c2ea3f,previous=Started,current=Prefetched,target=Prefetched,mediaTime=javax.media.Time@e94e92] 

Answer 1

你能實現ControllerListener接口，然後檢查ControllerEvents的事件。然後我們可以找出玩家創建失敗的階段