多线程Java Socket编程示例(http://www.blogjava.net/sterning/archive/2007/10/15/152940.html)

这篇做为学习孙卫琴<<Java网络编程精解>>的学习笔记吧.其中采用Java 5的ExecutorService来进行线程池的方式实现多线程,模拟客户端多用户向同一服务器端发送请求.
1.服务端

package sterning;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.*;

import java.util.concurrent.*;

public class MultiThreadServer {

private int port=8821;

private ServerSocket serverSocket;

private ExecutorService executorService;//线程池

private final int POOL_SIZE=10;//单个CPU线程池大小

public MultiThreadServer() throws IOException{

serverSocket=new ServerSocket(port);

//Runtime的availableProcessor()方法返回当前系统的CPU数目.

executorService=Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()*POOL_SIZE);

System.out.println("服务器启动");

}

public void service(){

while(true){

Socket socket=null;

try {

//接收客户连接,只要客户进行了连接,就会触发accept();从而建立连接

socket=serverSocket.accept();

executorService.execute(new Handler(socket));

} catch (Exception e) {

e.printStackTrace();

}

}

}

public static void main(String[] args) throws IOException {

new MultiThreadServer().service();

}

}

class Handler implements Runnable{

private Socket socket;

public Handler(Socket socket){

this.socket=socket;

}

private PrintWriter getWriter(Socket socket) throws IOException{

OutputStream socketOut=socket.getOutputStream();

return new PrintWriter(socketOut,true);

}

private BufferedReader getReader(Socket socket) throws IOException{

InputStream socketIn=socket.getInputStream();

return new BufferedReader(new InputStreamReader(socketIn));

}

public String echo(String msg){

return "echo:"+msg;

}

public void run(){

try {

System.out.println("New connection accepted "+socket.getInetAddress()+":"+socket.getPort());

BufferedReader br=getReader(socket);

PrintWriter pw=getWriter(socket);

String msg=null;

while((msg=br.readLine())!=null){

System.out.println(msg);

pw.println(echo(msg));

if(msg.equals("bye"))

break;

}

} catch (IOException e) {

e.printStackTrace();

}finally{

try {

if(socket!=null)

socket.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

}

2.客户端

package sterning;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.Socket;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

public class MultiThreadClient {

public static void main(String[] args) {

int numTasks = 10;

ExecutorService exec = Executors.newCachedThreadPool();

for (int i = 0; i < numTasks; i++) {

exec.execute(createTask(i));

}

}

// 定义一个简单的任务

private static Runnable createTask(final int taskID) {

return new Runnable() {

private Socket socket = null;

private int port=8821;

public void run() {

System.out.println("Task " + taskID + ":start");

try {

socket = new Socket("localhost", port);

// 发送关闭命令

OutputStream socketOut = socket.getOutputStream();

socketOut.write("shutdown/r/n".getBytes());

// 接收服务器的反馈

BufferedReader br = new BufferedReader(

new InputStreamReader(socket.getInputStream()));

String msg = null;

while ((msg = br.readLine()) != null)

System.out.println(msg);

} catch (IOException e) {

e.printStackTrace();

}

}

};

}

}

从而实现了多个客户端向服务器端发送请求,服务器端采用多线程的方式来处理的情况.再结合我之前的例子---Java基于Socket文件传输示例,就可以实现多线程文件的传输了