【IT168技术文档】

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();
}
}
}
}