package com.jiao.socketdemo;

 import java.io.BufferedReader;

 import java.io.BufferedWriter;

 import java.io.IOException;

 import java.io.InputStreamReader;

 import java.io.OutputStreamWriter;

 import java.net.ServerSocket;

 import java.net.Socket;

 public class ChatServer extends Thread {

     private ServerSocket server = null;

     private static final int PORT = 5550;

     private BufferedWriter writer;

     private BufferedReader reader;

     public ChatServer() throws IOException {

         CreateSocket();//初始化socket

     }

     @Override

     public void run() {

         Socket client;

         String txt;

         try {

             while (true) {

                 // 获取应答消息

                 client = ResponseSocket();

                 while (true) {

                     // 接受客户端信息

                     txt = ReceiveMsg(client);

                     System.out.println("客户端发来的消息：" + txt);

                     SendMsg(client, txt);

                     if (true)

                         break;

                 }

                 CloseSocket(client);

             }

         } catch (Exception e) {

             // TODO: handle exception

         }

     }

     //关闭连接

     private void CloseSocket(Socket client) throws IOException {

         reader.close();

         writer.close();

         client.close();

     }

     //封装发送消息的方法

     private void SendMsg(Socket socket, String Msg) throws IOException {

         writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));

         writer.write(Msg + "\n");

         writer.flush();

     }

     //封装接受消息的方法

     private String ReceiveMsg(Socket socket) throws IOException {

         reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));

         String txt = reader.readLine();

         return txt;

     }

     //接受消息

     private Socket ResponseSocket() throws IOException {

         Socket client = server.accept();

         return client;

     }

     //初始化socket

     private void CreateSocket() throws IOException {

         server = new ServerSocket(PORT, 100);

     }

 }

 // 创建聊天服务器

         ChatServer chatserver = new ChatServer();

         // 检测服务器是否已经启动，如果没有则启动服务器

         if (chatserver != null) {

             chatserver.start();

         }

 package com.example.socketclient;

 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;

 import android.app.Activity;

 import android.os.Bundle;

 public class MainActivity extends Activity {

     public static int SERVER_PORT = 5550;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

         new Thread() {

             public void run() {

                 message();

             }

         }.start();

     }

     private void message() {

         try {

             Socket client = RequestSocket("这里是服务器的IP", SERVER_PORT);

             SendMsg(client, "client send");

             String txt = ReceiveMsg(client);

             System.out.println("服务端返回数据：" + txt);

         } catch (Exception e) {

         }

     };

     // 客户端获取消息类

     private Socket RequestSocket(String host, int port)throws UnknownHostException, IOException {

         Socket socket = new Socket(host, port);

         return socket;

     }

     // 客户端发送消息类

     private void SendMsg(Socket socket, String msg) throws IOException {

         // 将要发送的消息写入Buffer 中

         BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));

         // 格式转换

         writer.write(msg.replace("\n", " ") + "\n");

         // 刷新，发送

         writer.flush();

     }

     // 客户端接收消息

     private String ReceiveMsg(Socket socket) throws IOException {

         // 写入读Buffer 中// 获取接收的消息到数据流中

         BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));

         // 读取消息到字符串中

         String Msg = reader.readLine();

         // 以字符串的方式返回消息

         return Msg;

     }

 }