The descendingIterator(E e) method of Deque Interface returns an iterator over the elements in this deque in a reverse sequential order. The elements will be returned in order from last(tail) to first(head). The returned iterator is a “weakly consistent” iterator.
Syntax:
Iterator descendingIterator()
Parameters: This method does not accept any parameter.
Return Value: This method returns an iterator over the elements in this deque in a proper sequence
Below programs illustrate the descendingIterator() method in Java:
Program 1: With the help of LinkedList.
import java.util.*;
public class GFG {
public static void main(String args[])
{
Deque<String> de_que = new LinkedList<String>();
de_que.add( "Welcome" );
de_que.add( "To" );
de_que.add( "Geeks" );
de_que.add( "4" );
de_que.add( "Geeks" );
Iterator iteratorVals = de_que.iterator();
System.out.println( "The iterator values"
+ " of deque are:" );
while (iteratorVals.hasNext()) {
System.out.println(iteratorVals.next());
}
}
}
|
Output:
The iterator values of deque are:
Welcome
To
Geeks
4
Geeks
Program 2:
import java.util.*;
public class GFG {
public static void main(String args[])
{
Deque<Integer> de_que = new LinkedList<Integer>();
de_que.add( 10 );
de_que.add( 15 );
de_que.add( 30 );
de_que.add( 20 );
de_que.add( 5 );
Iterator iteratorVals = de_que.iterator();
System.out.println( "The iterator values"
+ " of deque are:" );
while (iteratorVals.hasNext()) {
System.out.println(iteratorVals.next());
}
}
}
|
Output:
The iterator values of deque are:
10
15
30
20
5
Program 3: With the help of ArrayDeque.
import java.util.*;
public class GFG {
public static void main(String args[])
{
Deque<String> de_que = new ArrayDeque<String>();
de_que.add( "Welcome" );
de_que.add( "To" );
de_que.add( "Geeks" );
de_que.add( "4" );
de_que.add( "Geeks" );
Iterator iteratorVals = de_que.iterator();
System.out.println( "The iterator values"
+ " of deque are:" );
while (iteratorVals.hasNext()) {
System.out.println(iteratorVals.next());
}
}
}
|
Output:
The iterator values of deque are:
Welcome
To
Geeks
4
Geeks
Program 4: With the help of LinkedBlockingDeque.
import java.util.*;
import java.util.concurrent.LinkedBlockingDeque;
public class GFG {
public static void main(String args[])
{
Deque<String> de_que = new LinkedBlockingDeque<String>();
de_que.add( "Welcome" );
de_que.add( "To" );
de_que.add( "Geeks" );
de_que.add( "4" );
de_que.add( "Geeks" );
Iterator iteratorVals = de_que.iterator();
System.out.println( "The iterator values"
+ " of deque are:" );
while (iteratorVals.hasNext()) {
System.out.println(iteratorVals.next());
}
}
}
|
Output:
The iterator values of deque are:
Welcome
To
Geeks
4
Geeks
Program 5: With the help of ConcurrentLinkedDeque.
import java.util.*;
import java.util.concurrent.ConcurrentLinkedDeque;
public class GFG {
public static void main(String args[])
{
Deque<String> de_que = new ConcurrentLinkedDeque<String>();
de_que.add( "Welcome" );
de_que.add( "To" );
de_que.add( "Geeks" );
de_que.add( "4" );
de_que.add( "Geeks" );
Iterator iteratorVals = de_que.iterator();
System.out.println( "The iterator values"
+ " of deque are:" );
while (iteratorVals.hasNext()) {
System.out.println(iteratorVals.next());
}
}
}
|
Output:
The iterator values of deque are:
Welcome
To
Geeks
4
Geeks
Reference: https://docs.oracle.com/javase/8/docs/api/java/util/Deque.html#descendingIterator–
Feeling lost in the vast world of Backend Development? It's time for a change! Join our
Java Backend Development - Live Course and embark on an exciting journey to master backend development efficiently and on schedule.
What We Offer:
- Comprehensive Course
- Expert Guidance for Efficient Learning
- Hands-on Experience with Real-world Projects
- Proven Track Record with 100,000+ Successful Geeks
Last Updated :
21 Sep, 2018
Like Article
Save Article