Java study 2:The note of studying Socket which based TCP

 1 import java.io.BufferedReader;
 2 import java.io.IOException;
 3 import java.io.InputStreamReader;
 4 import java.io.PrintWriter;
 5 import java.net.ServerSocket;
 6 import java.net.Socket;
 7 
 8 public class ServerCode {
 9     private static int port =4444;
10     static Socket cs;
11     public static void main(String[] args) throws IOException {
12         ServerSocket ss=new ServerSocket(port);
13         cs=ss.accept();
14         System.out.println("Accept :"+cs);
15         try{
16             BufferedReader br=new BufferedReader(new InputStreamReader(cs.getInputStream()));
17             PrintWriter pr=new PrintWriter(cs.getOutputStream(),true);
18             while(true){
19                 String str=br.readLine();
20                 if(str.equals("bye")){
21                     break;
22                 }
23                 System.out.println("Client->Server:"+str);
24                 pr.println("send back to client:"+str);
25             }
26             br.close();
27             pr.close();
28         }catch(Exception e){
29             System.out.println("error:"+e);
30         }finally{
31             System.out.println("close the Server socket and the io.");
32             cs.close();
33             ss.close();
34         }
35         
36     }
37 
38 }

 1 import java.io.BufferedReader;
 2 import java.io.IOException;
 3 import java.io.InputStreamReader;
 4 import java.io.PrintWriter;
 5 import java.net.InetAddress;
 6 import java.net.Socket;
 7 
 8 public class ClientCode {
 9     public static void main(String[] args) throws IOException {
10         InetAddress add=InetAddress.getByName("localhost");
11         Socket cs=new Socket(add,4444);
12         System.out.println("socket = " + cs);
13         try{
14             BufferedReader br=new BufferedReader(new InputStreamReader(cs.getInputStream()));
15             PrintWriter pw=new PrintWriter(cs.getOutputStream(),true);
16             pw.println("Hello I‘m qixi");
17             String str=br.readLine();
18             System.out.println(str);
19             pw.println("bye");
20         }catch(Exception e){
21             System.out.println(e);
22         }finally{
23             System.out.println("close the Client socket and the io.");
24             cs.close();
25         }
26     }
27 }