The pollLast() method of Java.util.concurrent.TreeSet is an in-built function in Java which returns retrieves and removes the last (highest) element, or returns null if this set is empty.
Syntax:
public E pollLast()
Return Value: The function returns retrieves and removes the last (highest) element, or returns null if this set is empty.
Below programs illustrate the TreeSet.pollLast() method:
Program 1:
// Java program to demonstrate pollLast()// method of TreeSet  import java.util.*;  class TreeSetpollLastExample1 {    public static void main(String[] args)    {        // Creating a set object        TreeSet<Integer> set            = new TreeSet<Integer>();          // Adding elements to this set        for (int i = 10; i <= 50; i += 10)            set.add(i);          // Printing the content of the set        System.out.println("Contents of the set: " + set);          // Retrieving and removing Last element of the set        System.out.println("The Last element of the set: "                           + set.pollLast());          // Printing the content of the set after pollLast()        System.out.println("Contents of the set after pollLast: "                           + set);    }} |
Output:
Contents of the set: [10, 20, 30, 40, 50] The Last element of the set: 50 Contents of the set after pollLast: [10, 20, 30, 40]
Program 2:
// Java program to demonstrate pollLast()// method of TreeSet  import java.util.*;  class TreeSetpollLastExample2 {    public static void main(String[] args)    {        // Creating a set object        TreeSet<Integer> set            = new TreeSet<Integer>();          // Printing the content of the set        System.out.println("Contents of the set: "                           + set);          // Retrieving and removing Last element of the set        System.out.println("The Last element of the set: "                           + set.pollLast());    }} |
Output:
Contents of the set: [] The Last element of the set: null
