You can generate Random numbers in Java using the Random class available in java.util package. The following is a code which generates Random numbers between 0 and 100:

 import java.util.Random ;public class RandomGenerator {   public static void main(String args[]){	int value = 101;	Random  rm = new Random();	// rm.nextInt() can return Integer.MIN_VALUE (i.e -2147483648) and  Math.abs(Integer.MIN_VALUE) returns Integer.MIN_VALUE  int randInt = (rm.nextInt() & Integer.MAX_VALUE) % value;	System.out.println( " Random Number : " + randInt );  }}

You can define seed value using setSeed(long seedValue). There is also get random boolean using nextBoolean() method .

For complete listing visit:http://java.sun.com/products/jdk/1.2/docs/api/java/util/Random.html

Editor’s Note: The text has been changed from the original. Thanks to Kevin Mukhar for pointing out a bug in the original version and for suggesting the following links:
http://www.mindprod.com/gotchas.html#RANDOM andhttp://java.sun.com/people/linden/faq_b2.html#Core