Android通过C＃服务器通过TCP套接字接收图像

Question

I'm perfectly receiving images in Android from C# Server and streaming video. Problem is, I'm always opening and closing socket for each image. How can I receive images on creating a single socket only. Any help would be appreciated.

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    tv=(TextView)findViewById(R.id.textView1);
    etip=(EditText)findViewById(R.id.editText1);
//  etip.setText("192.168.1.5");
    etip.setText("10.0.2.2");
    imgview=(ImageView)findViewById(R.id.imageView1);
    btn=(Button)findViewById(R.id.button1);
    btn.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            try {
             try {
                    serverAddr = InetAddress.getByName(etip.getText().toString());
                } catch (UnknownHostException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                } 
                    Log.d("TCP", "C: Connecting..."); 
            }
            finally
            {

            }
            try
            {
                {
                 mHandler = new Handler();
                      mHandler.post(connectSocket);
                }       

}
            catch(Exception ex)
            {

            }

        }

    });
}

    private Runnable connectSocket=new Runnable() {

        @Override
        public void run() {

            {
                try { 
                socket = new Socket(serverAddr, 4444);
                            DataInputStream dis;
                            try { 
                                dis=new DataInputStream(socket.getInputStream());

                                int bytesRead;
                                byte[] pic = new byte[5000*1024];
                                bytesRead = dis.read(pic, 0, pic.length);
                                 bitmapimage = BitmapFactory.decodeByteArray(pic, 0, bytesRead);              


                            } catch(Exception e) { 
                                Log.e("TCP", "S: Error", e); 
                            } finally { 
                                socket.close(); 
                            } 

                        } catch (UnknownHostException e) { 
                            // TODO Auto-generated catch block 
                            Log.e("TCP", "C: UnknownHostException", e); 
                            e.printStackTrace(); 
                        } catch (IOException e) { 
                            // TODO Auto-generated catch block 
                            Log.e("TCP", "C: IOException", e); 
                            e.printStackTrace(); 
                        }
                        imgview.setImageBitmap(bitmapimage);
                        imgview.invalidate();

    }
             mHandler.postDelayed(this, 0);
        }   //run end
    };


    }

Answer 1

The socket won't close until you tell it to close like

socket.close();

FYI, http://docs.oracle.com/javase/7/docs/api/java/net/Socket.html#close() socket close function is also going to close any associative input/output streams

or the thread/application dies.

To make your application/thread constantly waits and reads,

http://docs.oracle.com/javase/6/docs/api/java/io/DataInputStream.html#read(byte[])

Reads some number of bytes from the contained input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown.

use read function of inputstream inside a loop and let it read new data whenever they are available.

However, I recommend you to try reduce number of socket connections as much as possible by limiting maximum socket connections and etc. This might prevent some attackers who want to just open up large amount of socket connections and do nothing to your server.