Java中的ArrayDeque descendingIterator()方法

Java.util.ArrayDeque.descendingIterator()方法用于返回一个迭代器，其元素与ArrayDeque相同，但按相反的顺序排列。

语法：

Iterator iterate_value = Array_Deque.descendingIterator();

参数： 该方法不接受任何参数。

返回值： 该方法遍历deque的元素并以相反的顺序返回值（迭代器）。

下面的程序说明Java.util.ArrayDeque.descendingIterator()方法：
程序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());
        }
    }
}

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

程序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());
        }
    }
}

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