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Java ArrayDeque Class: pollFirst() Method

public E pollFirst()

The pollFirst() method is used to retrieve and remove the first element of a given deque.

Package: java.util

Java Platform: Java SE 8

Syntax:

pollFirst()

Return Value:

the head of this deque, or null if this deque is empty

Return Value Type: E - the type of elements held in this collection

Pictorial Presentation

Java ArrayDeque Class: pollFirst() Method

Example: Java ArrayDeque Class: pollFirst() Method

import java.util.ArrayDeque;
import java.util.Deque;

public class Main {
   public static void main(String[] args) {
      
      // Create an array deque 
      Deque<Integer> deque = new ArrayDeque<Integer>(8);

      // use add() method to add elements in the deque
      deque.add(100);
      deque.add(200);
      deque.add(150);
      deque.add(95);        

      // Print all the elements of the original deque
      System.out.println("Elements of the original deque:");
      for (Integer number : deque) {
         System.out.println("Number = " + number);
      }

      int retval = deque.pollFirst();
      System.out.println("Removed element: " + retval);

      // printing all the elements available in deque after using pollFirst()
      for (Integer number : deque) {
         System.out.println("Number = " + number);
      }
   }
}

Output:

Elements of the original deque:
Number = 100
Number = 200
Number = 150
Number = 95
Removed element: 100
Number = 200
Number = 150
Number = 95

Java Code Editor:

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