import java.util.TreeSet; public class Main { public static void main(String[] args) { TreeSet<Integer> tSet = new TreeSet<Integer>(); tSet.add(new Integer("1")); tSet.add(new Integer("2")); tSet.add(new Integer("3")); Object[] objArray = tSet.toArray(); for (Object obj: objArray){ System.out.println(obj); } } }