LinkedBlockingDeque poll() method in Java Last Updated : 14 Sep, 2018 Comments Improve Suggest changes Like Article Like Report The poll() method of LinkedBlockingDeque returns the front element in the Deque container and deletes it. It returns null if the container is empty. Syntax: public E poll() Parameters: This method does not accept any parameters. Returns: This method returns front element of the Deque container if the container is not empty and deletes it. It returns null if the container is empty. Below programs illustrate poll() method of LinkedBlockingDeque: Program 1: Java // Java Program Demonstrate poll() // method of LinkedBlockingDeque import java.util.concurrent.LinkedBlockingDeque; import java.util.*; public class GFG { public static void main(String[] args) { // create object of LinkedBlockingDeque LinkedBlockingDeque<Integer> LBD = new LinkedBlockingDeque<Integer>(); // Add numbers to end of LinkedBlockingDeque LBD.add(7855642); LBD.add(35658786); LBD.add(5278367); LBD.add(74381793); // Print the queue System.out.println("Linked Blocking Deque: " + LBD); System.out.println("Front element in Deque: " + LBD.poll()); // One element is deleted as poll was called System.out.println("Linked Blocking Deque: " + LBD); } } Output: Linked Blocking Deque: [7855642, 35658786, 5278367, 74381793] Front element in Deque: 7855642 Linked Blocking Deque: [35658786, 5278367, 74381793] Program 2: Java // Java Program Demonstrate poll() // method of LinkedBlockingDeque // when Deque is empty import java.util.concurrent.LinkedBlockingDeque; import java.util.*; public class GFG { public static void main(String[] args) { // create object of LinkedBlockingDeque LinkedBlockingDeque<Integer> LBD = new LinkedBlockingDeque<Integer>(); // Add numbers to end of LinkedBlockingDeque LBD.add(7855642); LBD.add(35658786); LBD.add(5278367); LBD.add(74381793); // Print the queue System.out.println("Linked Blocking Deque: " + LBD); // empty deque LBD.clear(); System.out.println("Front element in Deque: " + LBD.poll()); } } Output: Linked Blocking Deque: [7855642, 35658786, 5278367, 74381793] Front element in Deque: null Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/LinkedBlockingDeque.html#poll() Comment More infoAdvertise with us Next Article LinkedBlockingDeque poll() method in Java G gopaldave Follow Improve Article Tags : Misc Java Java-Collections Java - util package Java-Functions Java-LinkedBlockingDeque +2 More Practice Tags : JavaJava-CollectionsMisc Similar Reads LinkedBlockingDeque peekLast() method in Java The peekLast() method of LinkedBlockingDeque returns the last element in the Deque container, but does not deletes it. It returns null if the container is empty. Syntax: public E peekLast() Parameters: This method does not accept any parameters. Returns: This method returns last element in the Deque 2 min read LinkedBlockingDeque offer() method in Java The offer(E e) method of LinkedBlockingDeque inserts the element passed in the parameter to the end of the Deque. If the container's capacity has exceeded, then it does not returns an exception as in case of add() and addFirst() function. Syntax: public boolean offer(E e) Parameters: This method acc 2 min read LinkedBlockingDeque element() method in Java The element() method of LinkedBlockingDeque returns the element at the front the container. It does not deletes the element in the container. This method returns the head of the queue represented by this deque. Syntax: public void element() Parameters: This method does not accept any parameter. 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