An interactive program to wish the user at different hours of the day.:

import java.util.*;

class TimeTest

{

public static void main(String as[]) throws Exception

{

Date d=new Date();

int h=d.getHours();

if(h<12)

System.out.println("Good Morning");

else if(h<16)

System.out.println("Good Afternoon");

else if(h<20)

System.out.println("Good Evening");

else

System.out.println("Time to sleep, Good night");

}

}