Network Protocol between mobile phones and PCs (1)

Network Protocol between mobile phones and PCs (1)

Now we use a computer as the server and a mobile phone as the client to implement communication between the mobile phone and the computer. First of all, it is similar to setting up a client on a mobile phone is similar to setting up a client on a computer. First, we create a server on the computer as follows:

 
 

  
  
The package mobile phone communicates with the PC;
  
  

  
  
Import java. io. IOException;
  
  

  
  

  
  

  
  

  
  
Import java.net. ServerSocket;
  
  
Import java.net. Socket;
  
  

  
  

  
  

  
  
Public class Server {
  
  

  
  
Public void setup (int port ){
  
  

  
  
Try {
  
  
// Create a server
  
  
ServerSocket host = new ServerSocket (port );
  
  
System. out. println ("communication port" + port + "enabled successfully ");
  
  
While (true ){
  
  
// Wait for client access
  
  
Socket socket = host. accept ();
  
  
System. out. println ("accessed ");
  
  
// Submit the communication with the client to the thread for processing.
  
  
ServerThread st = new ServerThread (socket );
  
  
// Enable the thread
  
  
St. start ();
  
  

  
  
}
  
  
} Catch (IOException e ){
  
  
// TODO Auto-generated catch block
  
  
E. printStackTrace ();
  
  
}
  
  

  
  

  
  
}
  
  
Public static void main (String [] args ){
  
  
// Input the port number
  
  
New Server (). setup (8888 );
  
  
}
  
  

  
  
}
 
 

Next, create a thread to process the input stream and output stream obtained by the socket:

 
 

  
  
The package mobile phone communicates with the PC;
  
  

  
  
Import java. io. DataInputStream;
  
  

  
  
Import java. io. DataOutputStream;
  
  
Import java. io. IOException;
  
  
Import java. io. InputStream;
  
  
Import java. io. OutputStream;
  
  
Import java.net. Socket;
  
  

  
  
Public class ServerThread extends Thread {
  
  
Private Socket socket;
  
  
Private DataOutputStream dos;
  
  
Public ServerThread (Socket socket ){
  
  
This. socket = socket;
  
  
}
  
  

  
  

  
  
Public void run (){
  
  
// Obtain the output input stream from the network connection socket
  
  
Try {
  
  
// Input stream
  
  
InputStream input = socket. getInputStream ();
  
  

  
  
DataInputStream dis = new DataInputStream (input );
  
  
// Obtain the output stream of the Client
  
  
Dos = new DataOutputStream (socket. getOutputStream ());
  
  
// Read the bytes sent from the client to the server
  
  
While (true ){
  
  
Int msgType = dis. readInt ();
  
  

  
  
Int len = dis. readInt ();
  
  
Byte [] bytes = new byte [len];
  
  
Dis. readFully (bytes );
  
  
String content = new String (bytes, "GB2312 ");
  
  
System. out. println ("the client says:" + content );
  
  

  
  

  
  
// This is sent to the client
  
  
String replyString = "the server received (" + content + ")";
  
  
Bytes = replyString. getBytes ("GB2312 ");
  
  

  
  
// Write to text 1
  
  
Dos. writeInt (1 );
  
  
// Write the output stream into the byte length
  
  
Dos. writeInt (bytes. length );
  
  
// Write into bytes
  
  
Dos. write (bytes );
  
  
// Refresh
  
  
Dos. flush ();
  
  
}
  
  

  
  

  
  

  
  

  
  
} Catch (IOException e ){
  
  
// TODO Auto-generated catch block
  
  
E. printStackTrace ();
  
  
}
  
  
}
  
  

  
  
}
 
 

These contents have been mentioned in the previous section, and we will not elaborate on them too much here.

Next we will focus on creating a client in Android. Here we will use eclipse with Android plug-in to compile

First, the interface is processed. I have defined a textview to display the chat content. editText is used as the input box, and a send button is used. This simple chat interface has been completed, as shown in the following figure, readers can beautify the page on their own:

Finally, remember to bind the send button to the specified function.