timeserver.java

《Java实例入门》所有实例的源代码。所有的源文件都是.java文件

import java.net.*;
import java.util.*;
import java.io.*;
import java.text.*;

public class timeServer {
  private static final int TIME_SERVER_PORT=13;
  private static final int SMALL_ARRAY=1;
  private static final int TIME_ARRAY=100;
  private DatagramSocket serverSocket=null;


  public timeServer() {
      try{
           serverSocket=new DatagramSocket(TIME_SERVER_PORT);
      }catch(Exception e){
          System.out.println(e);
      }
  }
  public void start(){
     System.out.println("server is running on port "+TIME_SERVER_PORT);
     while(true){
        try{
            byte[]  buffer=new byte[SMALL_ARRAY];
             DatagramPacket dataPacket=new DatagramPacket(buffer,buffer.length );
             serverSocket.receive(dataPacket);
             InetAddress clientAddress=dataPacket.getAddress();
            int clientPort=dataPacket.getPort() ;
             System.out.println("get the request from "+clientAddress+":"+clientPort);
             buffer=getTime();
             dataPacket=new DatagramPacket(buffer,buffer.length,clientAddress,clientPort );
             serverSocket.send(dataPacket);
        }catch(IOException e){

        }
     serverSocket.close();
    }
 }
  private byte[] getTime(){
     Date currentTime=new Date();
     SimpleDateFormat dateFormat=new SimpleDateFormat("yyyy MMMM dd,EEEE, HH:mm:ss");
     String timeString=dateFormat.format(currentTime);
     return timeString.getBytes() ;
  }
  public void finalize(){
     if(serverSocket!=null)
         serverSocket.close();
  }
  public static void main(String[] arg){
     timeServer server=new timeServer();
     server.start();
  }


}