multicastserverthread.java

java的书上例子

//MulticasServerThread.java

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

public class MulticastServerThread extends QuoteServerThread{

	private long FIVE_SECONDS=5000;

public MulticastServerThread() throws IOException{
  super("MulticastServerThread");
}
boolean moreQuotes=true;
public void run(){
while (moreQuotes){
try{
byte[] buf=new byte[256];

//construct quote
String dString =null;
Date date=null;
date=new Date();
if(dString==null)
dString= new String(date.toString());
else
dString = getNextQuote();
buf = dString.getBytes();

//send it
InetAddress group=InetAddress.getByName("230.0.0.1");
DatagramPacket packet =new DatagramPacket(buf, buf.length,group, 4446);
socket.send(packet);
//sleep for a while
try{
sleep((long) (Math.random()*FIVE_SECONDS));
}catch (InterruptedException e){}
}catch (IOException e){
 e.printStackTrace();
  moreQuotes=false;
}
}
socket. close();
}
}