我正在创建一个必须通过Wi-Fi和UDP协议接收压缩视频流的应用程序。视频流源是带有ARM微控制器和WLAN模块的DIY项目。尝试重新连接时遇到问题。当我第一次将learnObject var设置为true时，一切都可以。但是当我关闭该连接调用closeUdpSocket（）然后尝试连接一次时出现错误。错误是：java.net.SocketTimeoutException 在libcore.io.IoBridge.maybeThowAfterRecvForm（IoBridge.java:551）。你觉得怎么回事？ 谢谢你的帮助
public CameraView(Context context) {
super(context);
// TODO Auto-generated constructor stub
surfaceHolder = getHolder();
// Create Bitmap for video frame
bitmap = Bitmap.createBitmap(WIDTH, HEIGHT, Bitmap.Config.ARGB_8888/*Bitmap.Config.ALPHA_8*//*Bitmap.Config.RGB_565*/);
screenRect = new Rect(0, 0, 680, 510);
// Create and set paint color and its transparency
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
// paint.setARGB(100, 255, 0, 0);
// Prepare for drawing Rects
outerRect = new Rect(0, 0, 0, 0);
innerRect = new Rect(0, 0, 0, 0);
Log.d("S3", "stworzono bitmape");
}
public void onResumeCameraView() {
running = true;
thread = new Thread(this);
thread.start();
}
public void onPauseCameraView() {
boolean retry = true;
running = false;
while (retry) {
try {
thread.join();
retry = false;
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Override
public void run() {
long ticksPS = 1000 / FPS;
long startTime;
long sleepTime;
int blobx = MainActivity.blobx, bloby = MainActivity.bloby, blobw = MainActivity.blobw, blobh = MainActivity.blobh;
Canvas canvas;
int len = 0, n, j;
// TODO Auto-generated method stub
while (running) {
startTime = System.currentTimeMillis();
if (!/*isSurfaceCreated*/surfaceHolder.getSurface().isValid()) {
continue;
}
if (MainActivity.wlanStatus == 1)
Log.d("S3", "wlan activ");
else if (MainActivity.wlanStatus == 2)
Log.d("S3", "wlan deactivated");
else if (MainActivity.wlanStatus == 3)
Log.d("S3", "wlan error occured");
// canvas = null;
// try locking the canvas for exclusive pixel editing
// in the surface
// try {
// Create Canvas and set white background color
canvas = surfaceHolder.lockCanvas();
// synchronized (surfaceHolder) {
canvas.drawColor(0xFF5C5C5C);
if (MainActivity.learnObject == false && MainActivity.wlanStatus == MainActivity.WLAN_STATUS_DEINITIALIZED) {
MainActivity.wlanStatus = MainActivity.WLAN_STATUS_OFF;
closeUdpSocket();
Log.d("S3", "Socket zamkniety");
}
if (MainActivity.learnObject == true && MainActivity.wlanStatus == MainActivity.WLAN_STATUS_INITIALIZED) {
MainActivity.wlanStatus = MainActivity.WLAN_STATUS_RUNNING;
createUdpSocket();
Log.d("S3", "Socket utworzony");
}
if (MainActivity.learnObject && (MainActivity.wlanStatus == MainActivity.WLAN_STATUS_RUNNING)) {
buffer.rewind();
try {
sock.send(header);
if (D)
Log.d(TAG,"Start of receiving jpeg.");
len = 0;
j = 0;
do {
sock.receive(packet);
n = packet.getLength();
buffer.put(packet.getData(), 0, n);
if (D) {
Log.d(TAG, "Read: " + n + " bytes");
++j;
}
len += n;
// packet.setLength(1024);
} while (n == 1024);
if (D)
Log.d(TAG, "End of receiving jpeg, received: " + j + " packets");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
buffer.rewind();
if(frameData == null) { // do it only once at the beginning
frameData = new byte[IMAGE_SIZE];
if(D)
Log.d(TAG, "Memory allocated for frameData: " + IMAGE_SIZE);
}
buffer.get(frameData, 0, len); // copy data from main buffer into temporary frameData buffer
try {
retval = pixeltobmp(frameData, len, bitmap); // for mjpeg decoding we can use this external jpeg library
// bitmap = BitmapFactory.decodeStream(new ByteArrayInputStream(frameData, 0, len)); // or this Java built-in library
// bitmap = BitmapFactory.decodeByteArray(frameData, 0, len); // or this Java built-in library
if ((bitmap != null) && (retval == 0)) { // check if new bitmap is available
canvas.drawBitmap(bitmap, null, screenRect, paint);
} else {
if (D)
Log.d(TAG,"Error: Can't decode the incoming data");
}
freeCameraMemory();
} catch (Exception e) {}
}
// }
// } finally {
// // in case of an exception the surface is not left in
// // an inconsistent state
// if (canvas != null) {
// surfaceHolder.unlockCanvasAndPost(canvas);
// }
// } // end finally
surfaceHolder.unlockCanvasAndPost(canvas);
// SystemClock.sleep(10000);
sleepTime = ticksPS-(System.currentTimeMillis() - startTime);
try {
if (sleepTime > 0) {
Thread.sleep(sleepTime);
}
else {
Thread.sleep(10);
}
} catch (Exception e) {}
}
}
private void createUdpSocket()
{
try {
sock = new DatagramSocket();
sock.setSoTimeout(500); // 10000
header = new DatagramPacket("HEADER".getBytes(), 6, InetAddress.getByName(SERVER_ADDR), SERVER_PORT);
packet = new DatagramPacket(new byte[1024], 1024);
} catch (SocketException e) {
// TODO Auto-generated catch block
Toast.makeText(getContext(), "Error: Can't create Socket", Toast.LENGTH_SHORT).show();
e.printStackTrace();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
Toast.makeText(getContext(), "Error: Invalid Host IP Address", Toast.LENGTH_SHORT).show();
e.printStackTrace();
}
}
private void closeUdpSocket()
{
if (sock != null)
sock.close();
}
}