The pollLast() method of java.util.concurrent.ConcurrentSkipListSet 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 ConcurrentSkipListSet.pollLast() method:
Program 1:
// Java program to demonstrate pollLast() // method of ConcurrentSkipListSet import java.util.concurrent.*; class ConcurrentSkipListSetpollLastExample1 { public static void main(String[] args) { // Creating a set object ConcurrentSkipListSet<Integer> Lset = new ConcurrentSkipListSet<Integer>(); // Adding elements to this set for ( int i = 10 ; i <= 50 ; i += 10 ) Lset.add(i); // Printing the content of the set System.out.println( "Contents of the set: " + Lset); // Retrieving and removing Last element of the set System.out.println( "The Last element of the set: " + Lset.pollLast()); // Printing the content of the set after pollLast() System.out.println( "Contents of the set after pollLast: " + Lset); } } |
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 ConcurrentSkipListSet import java.util.concurrent.*; class ConcurrentSkipListSetpollLastExample2 { public static void main(String[] args) { // Creating a set object ConcurrentSkipListSet<Integer> Lset = new ConcurrentSkipListSet<Integer>(); // Printing the content of the set System.out.println( "Contents of the set: " + Lset); // Retrieving and removing Last element of the set System.out.println( "The Last element of the set: " + Lset.pollLast()); } } |
Contents of the set: [] The Last element of the set: null
Reference:
https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentSkipListSet.html#pollLast–