ConcurrentLinkedQueue poll() method in Java Last Updated : 26 Nov, 2018 Summarize Comments Improve Suggest changes Share Like Article Like Report The poll() method of ConcurrentLinkedQueue is used to remove and return the head of this ConcurrentLinkedQueue. If the ConcurrentLinkedQueue is empty then this method will return null. Syntax: public E poll() Returns: This method remove and returns the head of this ConcurrentLinkedQueue or null if this queue is empty. Below programs illustrate poll() method of ConcurrentLinkedQueue: Example 1: Java // Java Program Demonstrate poll() // method of ConcurrentLinkedQueue import java.util.concurrent.*; public class GFG { public static void main(String[] args) { // create an ConcurrentLinkedQueue ConcurrentLinkedQueue<Integer> queue = new ConcurrentLinkedQueue<Integer>(); // Add Numbers to queue queue.add(4353); queue.add(7824); queue.add(78249); queue.add(8724); // Displaying the existing ConcurrentLinkedQueue System.out.println("ConcurrentLinkedQueue: " + queue); // apply poll() int response1 = queue.poll(); // print after applying poll method System.out.println("Head: " + response1); // Displaying the existing ConcurrentLinkedQueue System.out.println("Current ConcurrentLinkedQueue: " + queue); } } Output: ConcurrentLinkedQueue: [4353, 7824, 78249, 8724] Head: 4353 Current ConcurrentLinkedQueue: [7824, 78249, 8724] Example 2: Java // Java Program Demonstrate poll() // method of ConcurrentLinkedQueue import java.util.concurrent.*; public class GFG { public static void main(String[] args) { // create an ConcurrentLinkedQueue ConcurrentLinkedQueue<String> queue = new ConcurrentLinkedQueue<String>(); // Add String to queue queue.add("Aman"); queue.add("Amar"); queue.add("Sanjeet"); queue.add("Rabi"); // Displaying the existing ConcurrentLinkedQueue System.out.println("ConcurrentLinkedQueue: " + queue); // apply poll() on queue String response1 = queue.poll(); // print after applying poll method System.out.println("Head: " + response1); // Displaying the existing ConcurrentLinkedQueue System.out.println("Current ConcurrentLinkedQueue: " + queue); // apply poll() on queue more than one time queue.poll(); queue.poll(); // Displaying the existing ConcurrentLinkedQueue System.out.println("After 2 poll() applied\n" + "ConcurrentLinkedQueue: " + queue); } } Output: ConcurrentLinkedQueue: [Aman, Amar, Sanjeet, Rabi] Head: Aman Current ConcurrentLinkedQueue: [Amar, Sanjeet, Rabi] After 2 poll() applied ConcurrentLinkedQueue: [Rabi] Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentLinkedQueue.html#poll-- Comment More infoAdvertise with us Next Article ConcurrentLinkedQueue offer() method in Java A AmanSingh2210 Follow Improve Article Tags : Java Java-Collections Java - util package java-basics Java-Functions java-queue Java-ConcurrentLinkedQueue +3 More Practice Tags : JavaJava-Collections Similar Reads ConcurrentLinkedQueue peek() method in Java The peek() method of ConcurrentLinkedQueue is used to return the head of the ConcurrentLinkedQueue. 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