Java Sound API 無法在 Web 應用程序的 UI 中單擊按鈕時停止錄制

Question

我正在使用 Java Sound API 來創建 Web 應用程序。用戶界面（UI）有一個按鈕，點擊開始錄制語音，錄制的音頻保存在音頻文件（.wav ext）中。UI 還有一個播放按鈕訪問相同的音頻文件並播放錄音。 目前，我正在錄制指定持續時間的音頻，該持續時間在我的應用程序中進行硬編碼，或者在錄制開始時作為參數從 UI 傳遞。但現在的要求是在單擊 UI 上的按鈕時停止錄制。

現在的問題是在捕獲音頻時，我正在使用以下代碼打開目標行：

---

公共無效捕獲（int record_time）{

        try {
         AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED, 44100, 16, 2, 4, 44100, false);
         DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
         if(!AudioSystem.isLineSupported(info))
         {
             System.out.println("Line not supported");}

         final TargetDataLine targetDataLine =        (TargetDataLine)AudioSystem.getLine(info);

         targetDataLine.open();
          targetDataLine.start();
         Thread thread = new Thread()
         {
             @Override public void run() 

             {
                 AudioInputStream audioStream = new AudioInputStream(targetDataLine);
                 File audioFile = new File(fileName);

                System.out.println("Recording is going to get saved in path :::: "+ audioFile.getAbsolutePath());
                 try{
                     AudioSystem.write(audioStream, AudioFileFormat.Type.WAVE, audioFile);
                 }
                 catch (IOException e){
                     e.printStackTrace();
                 }
                 System.out.println("Stopped Recording");
             }
         };
         thread.start();
         Thread.sleep(record_time*1000); 
         targetDataLine.stop();
         targetDataLine.close();
        System.out.println("Ended recording test");
        } catch (LineUnavailableException e) {
          System.err.println("Line unavailable: " + e);
          System.exit(-2);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

}

---

一旦記錄時間過去，上面的代碼將停止記錄。

但是我想要另一種方法，如下所示，當從 jsp 調用（停止按鈕單擊）時，它應該能夠獲得負責當前錄制並停止當前錄制的相同目標線對象。

下面的代碼對我不起作用，錄制繼續

---

public void stop(){
    try{
        System.out.println("stop :: in stop");
         AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED, 44100, 16, 2, 4, 44100, false);
         DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
         if(!AudioSystem.isLineSupported(info))
         {
             System.out.println("Line not supported");}

         final TargetDataLine targetDataLine = (TargetDataLine)AudioSystem.getLine(info);
         System.out.println("stop Recording....");

         System.out.println("targetDataLine.getLineInfo() in stop:::::::"+targetDataLine.getLineInfo());
         System.out.println("targetDataLine.isActive() in stop:::::::"+targetDataLine.isActive());
         System.out.println("targetDataLine.isOpen() in stop:::::::"+targetDataLine.isOpen());

         targetDataLine.stop();
         targetDataLine.close();
    }
     catch (Exception e) {
          System.err.println("Line unavailable: " + e);
     }
}

---

請提出一些解決方案。

另一件事可能..不確定但可能有一些作用是我從我的servlet調用這些方法的方式..下面是代碼....

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    String action = request.getParameter("buttonName");
    String record_time = request.getParameter("time");
    System.out.println("action:::"+action +"time in minutes:::"+ record_time);
    int record_time_int =(Integer.parseInt(record_time));
    String fileName = "studentXYZ.wav";

    System.out.println("action:::"+action +"----wavfile:::"+fileName+"time in minutes:::"+ record_time);

    Recorder01 record = new Recorder01();


    if (action != null && (action.equalsIgnoreCase("Capture")) ){

        record.capture(fileName, action,record_time_int);
                request.setAttribute("fileName", fileName);
                request.getRequestDispatcher("/recordAudio.jsp").forward(request, response);

    }

    else if (action != null && action.equalsIgnoreCase("play")) {
        Recorder01 playsound = new Recorder01();
        playsound.play(fileName);
        System.out.println("finished playing recording");
        request.setAttribute("fileName", fileName);
            request.getRequestDispatcher("/recordAudio.jsp").forward(request, response);

    }

    else if(action!=null && action.equalsIgnoreCase("Stop")){
        System.out.println("stop recording called");
        record.stop();
            request.getRequestDispatcher("/recordAudio.jsp").forward(request, response);

    }
}

Answer 1

private TargetDataLine targetDataLine;

public void capture() {

    if (targetDataLine == null) {

        try {
            AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED, 44100, 16, 2, 4, 44100, false);
            DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
            if (!AudioSystem.isLineSupported(info)) {
                System.out.println("Line not supported");
            }

            targetDataLine = (TargetDataLine) AudioSystem.getLine(info);

            targetDataLine.open();
            targetDataLine.start();
            Thread thread = new Thread() {
                @Override
                public void run() {
                    AudioInputStream audioStream = new AudioInputStream(targetDataLine);
                    File audioFile = new File(fileName);

                    System.out.println("Recording is going to get saved in path :::: " + audioFile.getAbsolutePath());
                    try {
                        AudioSystem.write(audioStream, AudioFileFormat.Type.WAVE, audioFile);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                    System.out.println("Stopped Recording");
                }
            };
            thread.start();
        } catch (LineUnavailableException e) {
            System.err.println("Line unavailable: " + e);
            System.exit(-2);
        }
    }
}

public void stop() {
    if (targetDataLine != null) {
        System.out.println("stop :: in stop");
        targetDataLine.stop();
        targetDataLine.close();
        targetDataLine = null;
    }
}