Retrieving the Ends for a TreeSet : TreeSet « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. TreeSet

You can use the first() and last() methods of TreeSet to get the elements at the ends of the tree:

public Object first()
public Object last()

The first() element is the one that is ordered first in the set, while last() is last.

A NoSuchElementException will be thrown by either method if there are no elements in the set.

import java.util.Arrays;
import java.util.Set;
import java.util.TreeSet;

public class MainClass {
  public static void main(String args[]) throws Exception {
    String elements[] = { "A", "C", "D", "G", "F" };
    TreeSet set = new TreeSet(Arrays.asList(elements));
    System.out.println(set);
    System.out.println(set.first());
    System.out.println(set.last());
  }
}

[A, C, D, F, G]
A
G