Also available as HashSetPlay.java

/**
 * Title: HashSetPlay
 * Description: Simple example of using HashSet
 * @author hollingd@cs.rpi.edu
 */
import java.util.*;

class HashSetPlay {

        public static void main(String [] args ) {

                // Create an ArrayList object
                HashSet x = new HashSet();

                // Populate with 10 random Integer objects
                Random r = new Random();

                for (int i=0;i<20;i++) {
                        if (! x.add( new Integer(r.nextInt(100)))) {
                                System.out.println("Duplicate!");
                        }
                                
                }
                System.out.println("Set: " + x);

                // print all elements of x using iterator
                Iterator i = x.iterator();

                while (i.hasNext()) {
                        int y = ((Integer) i.next()).intValue();
                        System.out.print( y + " ");
                }
                System.out.println();

        }




}