Deque element() method in Java

Deque descendingIterator() Method in Java

Last Updated : 01 Dec, 2024

The descendingIterator() method of the Deque Interface returns an iterator over the elements in this deque in reverse order. The elements will be returned from the last to the first order. This can be used with any class implementing the Deque Interface like LinkedList, ArrayDeque, LinkedBlockingDeque, etc.

Syntax:

Iterator descendingIterator()

Example 1: Here, we are using the LinkedList as Deque.

Java

// Java program to show the use of Deque
// descendingIterator() method
import java.util.*;

public class GFG {

    public static void main(String[] args)
    {

        // Creating an Empty Deque
        Deque<Integer> dq = new LinkedList<>();

        // Adding elements
        dq.add(1);
        dq.add(2);
        dq.add(3);
        dq.add(4);

        // Using descendingIterator() method to
        // get reverse order of elements
        Iterator<Integer> iterator = dq.descendingIterator();

        // Printing elements in reverse order
        while (iterator.hasNext()) {
            System.out.println(iterator.next());
        }
    }
}

Output

Example 2: Here, we are using the ArrayDeque as Deque.

Java

// Java program to show the use of Deque
// descendingIterator() method
import java.util.*;

public class GFG {

    public static void main(String[] args)
    {

        // Creating an Empty Deque
        Deque<String> dq = new ArrayDeque<>();

        // Adding elements
        dq.add("Hello");
        dq.add("Geeks");
        dq.add("How Are");
        dq.add("You");

        // Using descendingIterator() method to
        // get reverse order of elements
        Iterator<String> iterator = dq.descendingIterator();

        // Printing elements in reverse order
        while (iterator.hasNext()) {
            System.out.println(iterator.next());
        }
    }
}

Output

You
How Are
Geeks
Hello

Deque element() method in Java

G

gopaldave

Improve

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