Java socket 实现tcp通信

客户端：Client

 package socket;

 import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;
 import java.net.Socket;
 import java.net.UnknownHostException;

 public class Client {
     private static final String SERVER_IP = "localhost";
     private static final int PORT = 9999;

     public static void main(String [] args) throws UnknownHostException, IOException{
         Socket socket = new Socket(SERVER_IP, PORT);
 //      BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getOutputStream()));
         BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
         writer.write("message");
         writer.flush();
         socket.close();
     }
 }

服务器端：Server

 package socket;

 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.ServerSocket;
 import java.net.Socket;

 public class Server {
     private static final int PORT = 9999;
     public static void main(String [] args) throws IOException{
         ServerSocket server = new ServerSocket(PORT);
         Socket socket = server.accept();
         BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
         System.out.println("server : "+reader.readLine());
         socket.close();
     }

 }