ArrayDeque descendingIterator() Method in Java

The Java.util.ArrayDeque.descendingIterator() method is used to return an iterator of the same elements as the ArrayDeque but in the reverse order.

Syntax:

Iterator iterate_value = Array_Deque.descendingIterator();

Parameters: The method does not take any parameter.

Return Value: The method iterates over the elements of the deque and returns the values(iterators) in reverse order.

Below programs illustrate the Java.util.ArrayDeque.descendingIterator() method:
Program 1:

// Java code to illustrate descendingIterator() 
import java.util.*; 
  
public class ArrayDequeDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty ArrayDeque 
        Deque<String> de_que = new ArrayDeque<String>(); 
  
        // Use add() method to add elements into the Queue 
        de_que.add("Welcome"); 
        de_que.add("To"); 
        de_que.add("Geeks"); 
        de_que.add("4"); 
        de_que.add("Geeks"); 
  
        // Displaying the ArrayDeque 
        System.out.println("ArrayDeque: " + de_que); 
  
        // Creating a desc_iterator 
        Iterator value = de_que.descendingIterator(); 
  
        // Displaying the values after iterating through the Deque 
        // in reverse order 
        System.out.println("The iterator values are: "); 
        while (value.hasNext()) { 
            System.out.println(value.next()); 
        } 
    } 
} 

Output:

ArrayDeque: [Welcome, To, Geeks, 4, Geeks]
The iterator values are: 
Geeks
4
Geeks
To
Welcome

Program 2:

// Java code to illustrate descendingIterator() 
import java.util.*; 
  
public class ArrayDequeDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty ArrayDeque 
        Deque<Integer> de_que = new ArrayDeque<Integer>(); 
  
        // Use add() method to add elements into the Queue 
        de_que.add(10); 
        de_que.add(15); 
        de_que.add(30); 
        de_que.add(20); 
        de_que.add(5); 
  
        // Displaying the ArrayDeque 
        System.out.println("ArrayDeque: " + de_que); 
  
        // Creating a desc_iterator 
        Iterator value = de_que.descendingIterator(); 
  
        // Displaying the values after iterating through the Deque 
        // in reverse order 
        System.out.println("The iterator values are: "); 
        while (value.hasNext()) { 
            System.out.println(value.next()); 
        } 
    } 
} 

Output:

ArrayDeque: [10, 15, 30, 20, 5]
The iterator values are: 
5
20
30
15
10

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