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Showing content from https://www.geeksforgeeks.org/java/queue-poll-method-in-java/ below:

Queue poll() method in Java

Last Updated : 11 Jul, 2025

The

poll()

method of

Queue Interface

returns and removes the element at the front end of the container. It deletes the element in the container. The method does not throws an exception when the Queue is empty, it returns

null

instead.

Syntax:

E poll()

Returns:

This method returns the

element at the front

of the container or the head of the Queue. It returns

null

when the Queue is empty. Below programs illustrate poll() method of Queue:

Program 1:

With the help of

LinkedList

Java


 // Java Program Demonstrate poll()
// method of Queue

import java.util.*;

public class GFG {
    public static void main(String[] args)
        throws IllegalStateException
    {

        // create object of Queue
        Queue<Integer> Q
            = new LinkedList<Integer>();

        // Add numbers to end of Queue
        Q.add(7855642);
        Q.add(35658786);
        Q.add(5278367);
        Q.add(74381793);

        // print queue
        System.out.println("Queue: " + Q);

        // print head and deletes the head
        System.out.println("Queue's head: " + Q.poll());

        // print head and deleted the head
        System.out.println("Queue's head: " + Q.poll());
    }
}

Output:

Queue: [7855642, 35658786, 5278367, 74381793]
Queue's head: 7855642
Queue's head: 35658786

Program 2:

To Demonstrate poll() method of Queue when the Queue becomes empty

Java


 // Java Program Demonstrate poll()
// method of Queue when the Queue becomes empty

import java.util.*;

public class GFG {
    public static void main(String[] args)
        throws IllegalStateException
    {

        // create object of Queue
        Queue<Integer> Q
            = new LinkedList<Integer>();

        // Add numbers to end of Queue
        Q.add(423);
        Q.add(3432);

        // print queue
        System.out.println("Queue: " + Q);

        // print head and deletes the head
        System.out.println("Queue's head: " + Q.poll());

        // print head and deleted the head
        System.out.println("Queue's head: " + Q.poll());

        // print queue
        System.out.println("Queue: " + Q);

        // print null as Queue is empty now
        System.out.println("Queue's head: " + Q.poll());
    }
}

Output:

Queue: [423, 3432]
Queue's head: 423
Queue's head: 3432
Queue: []
Queue's head: null

Program 3:

With the help of

ArrayDeque

Java


 // Java Program Demonstrate poll()
// method of Queue

import java.util.*;

public class GFG {
    public static void main(String[] args)
        throws IllegalStateException
    {

        // create object of Queue
        Queue<Integer> Q
            = new ArrayDeque<Integer>();

        // Add numbers to end of Queue
        Q.add(7855642);
        Q.add(35658786);
        Q.add(5278367);
        Q.add(74381793);

        // print queue
        System.out.println("Queue: " + Q);

        // print head and deletes the head
        System.out.println("Queue's head: " + Q.poll());

        // print head and deleted the head
        System.out.println("Queue's head: " + Q.poll());
    }
}

Output:

Queue: [7855642, 35658786, 5278367, 74381793]
Queue's head: 7855642
Queue's head: 35658786

Program 4:

With the help of

ConcurrentLinkedDeque

Java


 // Java Program Demonstrate poll()
// method of Queue

import java.util.*;
import java.util.concurrent.ConcurrentLinkedDeque;

public class GFG {
    public static void main(String[] args)
        throws IllegalStateException
    {

        // create object of Queue
        Queue<Integer> Q
            = new ConcurrentLinkedDeque<Integer>();

        // Add numbers to end of Queue
        Q.add(7855642);
        Q.add(35658786);
        Q.add(5278367);
        Q.add(74381793);

        // print queue
        System.out.println("Queue: " + Q);

        // print head and deletes the head
        System.out.println("Queue's head: " + Q.poll());

        // print head and deleted the head
        System.out.println("Queue's head: " + Q.poll());
    }
}

Output:

Queue: [7855642, 35658786, 5278367, 74381793]
Queue's head: 7855642
Queue's head: 35658786

Program 5:

With the help of

LinkedBlockingDeque

Java


 // Java Program Demonstrate poll()
// method of Queue

import java.util.*;
import java.util.concurrent.LinkedBlockingDeque;

public class GFG {
    public static void main(String[] args)
        throws IllegalStateException
    {

        // create object of Queue
        Queue<Integer> Q
            = new LinkedBlockingDeque<Integer>();

        // Add numbers to end of Queue
        Q.add(7855642);
        Q.add(35658786);
        Q.add(5278367);
        Q.add(74381793);

        // print queue
        System.out.println("Queue: " + Q);

        // print head and deletes the head
        System.out.println("Queue's head: " + Q.poll());

        // print head and deleted the head
        System.out.println("Queue's head: " + Q.poll());
    }
}

Output:

Queue: [7855642, 35658786, 5278367, 74381793]
Queue's head: 7855642
Queue's head: 35658786

Reference: https://docs.oracle.com/javase/8/docs/api/java/util/Queue.html#poll--

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