多线程Java Socket编程示例

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.
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