java socket和多线程（Thread）实例

1. socket通信：有客户端和服务端的socket代码。

2. 多线程：客户端和服务端各用一线程发送信息；服务端另有一监听线程，用于把超时的信息删除。

    这里应用到了同步，使两个线程可以操作同一个map。

代码：（类全在同一个包内）
server端：

import java.io.BufferedReader;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.ServerSocket;import java.net.Socket;import java.util.Collections;import java.util.concurrent.TimeUnit;import java.util.HashMap;import java.util.Map;public class ServerNet {// 以毫秒为单位 private final static long timeLimit = 10000 ;private Map<String,String> map = Collections.synchronizedMap(new HashMap<String,String>());public void ServerSocketNet(){try{ ServerSocket ss = new ServerSocket(6060); Socket s = ss.accept(); // 用于获取客户端传输来的信息 BufferedReader buff = new BufferedReader(new InputStreamReader(s.getInputStream())); // 用于获取服务端准备响应的信息 BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); // 发送服务端准备响应的信息 PrintWriter pw = new PrintWriter(s.getOutputStream(),true); pw.println("您已经成功建立连接!"); new ServerOutNet(pw, in); new ServerTimeListener(map, timeLimit); // 显示客户端的传输来的信息 while(true){ String str = buff.readLine(); if(str.equals("exit")){ break; }else{ map.put(ServerHelper.getInstance().getMapKey(), str); System.out.println(str + " map.size: " + map.size()); } System.out.println("To Client:"); Thread.sleep(100);}s.close(); }catch(Exception e){ e.printStackTrace(); }} public static void main(String[] args){ new ServerNet().ServerSocketNet(); }}/** * server发送线程 向客户端发送响应信息 * @author ids-user * */class ServerOutNet extends Thread{private PrintWriter printWriter;private BufferedReader bufferedReader;ServerOutNet(PrintWriter pw,BufferedReader in){this.printWriter = pw;this.bufferedReader = in;start(); }public void run(){while(true){try{String inStr = bufferedReader.readLine();if(inStr.equals("exit")){printWriter.close();bufferedReader.close();break;}else{printWriter.println("From Server: " + inStr);}sleep(300);}catch(Exception e){printWriter = null;bufferedReader = null;throw new RuntimeException(e);}} }}// 时间监听线程类。class ServerTimeListener extends Thread{private long timeLimit;Map<String, String> map = new HashMap<String, String>();// 单例//private ServerTimeListener(){}//private final static ServerTimeListener stl = new ServerTimeListener();//public static ServerTimeListener getInstance(){//return stl;//}ServerTimeListener(Map<String, String> map , long timeLimit){this.map = map;this.timeLimit = timeLimit;start();}public void run(){while(true){try{// 循环map long currentTime = System.currentTimeMillis(); for(String mapKey : map.keySet()){ long oldTime = Long.parseLong(mapKey.substring(0, mapKey.indexOf("_"))); System.out.println("currentTime - oldTime=" + (currentTime - oldTime)); if(currentTime - oldTime >= timeLimit){ map.remove(mapKey); } } TimeUnit.MILLISECONDS.sleep(timeLimit);}catch(Exception e){throw new RuntimeException(e);}} }} 

 

 

服务器端辅助类：ServerHelper

 

import java.util.Random;public class ServerHelper {// 单例private ServerHelper(){}private final static ServerHelper helper = new ServerHelper();public static ServerHelper getInstance(){return helper;}// 构建map的key值public String getMapKey(){Random random = new Random();String mapKey = System.currentTimeMillis() + "_" + random.nextInt(1000);System.out.println("map key: " + mapKey);return mapKey;}}

 

Client端：

 

import java.io.BufferedReader;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.Socket;import java.util.concurrent.Executors;import java.util.concurrent.ExecutorService;public class ClientNet {public static void main(String[] args){try{Socket s = new Socket("127.0.0.1",6060);// 用于获取服务端传输来的信息BufferedReader buff = new BufferedReader(new InputStreamReader(s.getInputStream()));// 用于获取客户端准备响应的信息BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in)); // 发送客户端准备传输的信息PrintWriter printWriter = new PrintWriter(s.getOutputStream(),true); printWriter.println("有客房端请求连接!"); // 客户端使用线程池连接服务端// ExecutorService executorService = Executors.newCachedThreadPool();// executorService.execute(new ClientOutNet(printWriter,bufferedReader)); new ClientOutNet(printWriter,bufferedReader); while(true){ // 显示服务端的响应信息 String str = buff.readLine(); if(str != null){ System.out.println(str);}// System.out.println("To Server:"); Thread.sleep(100);} }catch(Exception e){e.printStackTrace();}}}/** * Client 发送线程 ，向服务端发送信息 * @author ids-user */class ClientOutNet extends Thread{private PrintWriter printWriter;private BufferedReader bufferedReader;ClientOutNet(PrintWriter pw,BufferedReader in){this.printWriter = pw;this.bufferedReader=in;start(); }public void run(){while(true){try{String inStr = bufferedReader.readLine();if(inStr.equals("exit")){printWriter.close();bufferedReader.close();break;}else{printWriter.println("From Client: " + inStr);}sleep(300);}catch(Exception e){printWriter = null;bufferedReader = null;throw new RuntimeException(e);}} }}