The Java Program: NetworkTime.java

  1 // NetworkTime.java -- NTP client
  2 
  3 import java.net.Socket;
  4 import java.net.UnknownHostException;
  5 import java.io.PrintWriter;
  6 import java.io.BufferedReader;
  7 import java.io.InputStreamReader;
  8 import java.io.IOException;
  9 
 10 public class NetworkTime {
 11 
 12    final static int port = 13;  // "daytime" protol
 13 
 14    public static void main (String [] args) {
 15 
 16       final String hostname = args.length>0?args[0]:"nist1.columbiacountyga.gov";
 17 
 18       try {
 19          final Socket         so = new Socket (hostname, port);
 20          final PrintWriter    pw = new PrintWriter (so.getOutputStream());
 21          pw.println();
 22          final BufferedReader in = new BufferedReader (
 23             new InputStreamReader (so.getInputStream()));
 24 
 25          final String time = in.readLine();
 26          System.out.println (time.length());
 27          System.out.println (so.getInetAddress() + " says it is " + time);
 28     
 29          so.close();
 30       } catch (IOException e) {
 31          e.printStackTrace (System.err);
 32       }
 33    }
 34 }