作为应用程序工作但不作为小程序工作的 Java 类

Question

我是一名android开发人员，对java web开发没有广泛的了解，所以如果问题有点奇怪，请多多包涵。我创建了一个 java 类，它应该从 android 应用程序接收音频形式的数据包，并在 PC 扬声器上播放。该应用程序基本上是一个从手机到服务器的流媒体应用程序。该类(class)作为应用程序运行良好。

这是类的代码:

class Server {

AudioInputStream audioInputStream;
static AudioInputStream ais;
static AudioFormat format;
static boolean status = true;
static int port = 50005;
static int sampleRate = 8000;



public static void main(String args[]) throws Exception {


    DatagramSocket serverSocket = new DatagramSocket(50005);

    /**
     * Formula for lag = (byte_size/sample_rate)*2
     * Byte size 9728 will produce ~ 0.45 seconds of lag. Voice slightly broken.
     * Byte size 1400 will produce ~ 0.06 seconds of lag. Voice extremely broken.
     * Byte size 4000 will produce ~ 0.18 seconds of lag. Voice slightly more broken then 9728.
     */

    byte[] receiveData = new byte[5000];

    format = new AudioFormat(sampleRate, 16, 1, true, false);

    while (status == true) {
        DatagramPacket receivePacket = new DatagramPacket(receiveData,
                receiveData.length);

        serverSocket.receive(receivePacket);

        ByteArrayInputStream baiss = new ByteArrayInputStream(
                receivePacket.getData());

        ais = new AudioInputStream(baiss, format, receivePacket.getLength());
        toSpeaker(receivePacket.getData());

    }



}

public static void toSpeaker(byte soundbytes[]) {
    try {

        DataLine.Info dataLineInfo = new DataLine.Info(SourceDataLine.class, format);
        SourceDataLine sourceDataLine = (SourceDataLine) AudioSystem.getLine(dataLineInfo);

        sourceDataLine.open(format);

        FloatControl volumeControl = (FloatControl) sourceDataLine.getControl(FloatControl.Type.MASTER_GAIN);
        volumeControl.setValue(6.0206f);

        sourceDataLine.start();
        sourceDataLine.open(format);

        sourceDataLine.start();

        System.out.println("format? :" + sourceDataLine.getFormat());

        sourceDataLine.write(soundbytes, 0, soundbytes.length);
        System.out.println(soundbytes.toString());
        sourceDataLine.drain();
        sourceDataLine.close();
    } catch (Exception e) {
        System.out.println("Not working in speakers...");
        e.printStackTrace();
    }
}
}

现在我想将该类转换为小程序，以便我可以将其部署为 Web 应用程序。这是小程序的代码:

public class AppletTest extends Applet {


    AudioInputStream audioInputStream;
    static AudioInputStream ais;
    static AudioFormat format;
    static boolean status = true;
    static int port = 50005;
    static int sampleRate = 8000;



    public void init()
    {

    }

    public void stop()
    {

    }



    public void listening()
    {
         DatagramSocket serverSocket = null;
        try {
            serverSocket = new DatagramSocket(50005);
        } catch (SocketException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

            /**
             * Formula for lag = (byte_size/sample_rate)*2
             * Byte size 9728 will produce ~ 0.45 seconds of lag. Voice slightly broken.
             * Byte size 1400 will produce ~ 0.06 seconds of lag. Voice extremely broken.
             * Byte size 4000 will produce ~ 0.18 seconds of lag. Voice slightly more broken then 9728.
             */

            byte[] receiveData = new byte[5000];

            format = new AudioFormat(sampleRate, 16, 1, true, false);

            while (status == true) {
                DatagramPacket receivePacket = new DatagramPacket(receiveData,
                        receiveData.length);

                try {
                    serverSocket.receive(receivePacket);
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

                ByteArrayInputStream baiss = new ByteArrayInputStream(
                        receivePacket.getData());

                ais = new AudioInputStream(baiss, format, receivePacket.getLength());
                toSpeaker(receivePacket.getData());

            }
    }



    public static void toSpeaker(byte soundbytes[]) {
        try {

            DataLine.Info dataLineInfo = new DataLine.Info(SourceDataLine.class, format);
            SourceDataLine sourceDataLine = (SourceDataLine) AudioSystem.getLine(dataLineInfo);

            sourceDataLine.open(format);

            FloatControl volumeControl = (FloatControl) sourceDataLine.getControl(FloatControl.Type.MASTER_GAIN);
            volumeControl.setValue(6.0206f);

            sourceDataLine.start();
            sourceDataLine.open(format);

            sourceDataLine.start();

            System.out.println("format? :" + sourceDataLine.getFormat());

            sourceDataLine.write(soundbytes, 0, soundbytes.length);
            System.out.println(soundbytes.toString());
            sourceDataLine.drain();
            sourceDataLine.close();
        } catch (Exception e) {
            System.out.println("Not working in speakers...");
            e.printStackTrace();
        }
    }


}

调用小程序的html代码:

<HTML>
<TITLE>Applet Test</TITLE>
<HEAD></HEAD>
<BODY>
<applet code="AppletTest.class" height="200" width="500">Applet</applet>
</BODY>
</HTML>

小程序我已经托管了here

这是以数据包形式发送声音的android Activity :

public class SendActivity extends Activity {
    private Button startButton, stopButton;

    public byte[] buffer;
    public static DatagramSocket socket;
    private int port = 50005;
    AudioRecord recorder;

    private int sampleRate = 8000;
    @SuppressWarnings("deprecation")
    private int channelConfig = AudioFormat.CHANNEL_IN_MONO;
    private int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
    int minBufSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig,
            audioFormat);
    private boolean status = true;


    int bufferSizeInBytes;
    int bufferSizeInShorts;
      int shortsRead;
      short audioBuffer[];

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_send);

        startButton = (Button) findViewById(R.id.start_button);
        stopButton = (Button) findViewById(R.id.stop_button);

        startButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                status = true;
                startStreaming();


            }

        });

        stopButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                status = false;
                recorder.release();
                Log.d("VS", "Recorder released");

            }

        });

        minBufSize += 5120;
        System.out.println("minBufSize: " + minBufSize);
    }


    public void startStreaming() {

        Thread streamThread = new Thread(new Runnable() {

            @Override
            public void run() {
                try {

                    DatagramSocket socket = new DatagramSocket();
                    Log.d("VS", "Socket Created");

                    byte[] buffer = new byte[minBufSize];

                    Log.d("VS", "Buffer created of size " + minBufSize);
                    DatagramPacket packet;

                    final InetAddress destination = InetAddress
                            .getByName("http://abhideepmallick.byethost16.com/");

//final InetAddress destination = InetAddress.getByName("192.168.1.20");//machine IP

Log.d("VS", "Address retrieved");

                    recorder = new AudioRecord(MediaRecorder.AudioSource.VOICE_RECOGNITION,
                            sampleRate, channelConfig, audioFormat,
                            minBufSize * 10);
                    Log.d("VS", "Recorder initialized");

                    recorder.startRecording();

                    while (status == true) {

                        // reading data from MIC into buffer
                        minBufSize = recorder.read(buffer, 0, buffer.length);

                        // putting buffer in the packet
                        packet = new DatagramPacket(buffer, buffer.length,
                                destination, port);

                        socket.send(packet);
                        System.out.println("MinBufferSize: " + minBufSize);

                    }

                } catch (UnknownHostException e) {
                    Log.e("VS", "UnknownHostException");
                } catch (IOException e) {
                    e.printStackTrace();
                    Log.e("VS", "IOException");
                }
            }

        });
        streamThread.start();
    }


}

Android 布局文件:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".SendActivity" >



    <Button
        android:id="@+id/stop_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/start_button"
        android:layout_alignBottom="@+id/start_button"
        android:layout_toRightOf="@+id/start_button"
        android:text="Stop" />

    <Button
        android:id="@+id/start_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="79dp"
        android:layout_marginTop="163dp"
        android:text="Start" />

</RelativeLayout>

我应该怎么做才能使 java 类作为小程序工作？

Answer 1

我想您设法让浏览器的 java 插件是最新的，以便启动小程序。

小程序也有像 Activity 一样的生命周期。

init()方法就像一个构造函数，start()方法的目的是通知applet开始执行。

因此覆盖启动方法并从那里调用您的监听方法。如需更多信息，您可以浏览此幻灯片:http://de.slideshare.net/myrajendra/applet-life-cycle

可在此处找到示例:http://www.ugrad.cs.ubc.ca/~cs219/CourseNotes/Java/applets/lifecycle.html