Iterate a LinkedList in Reverse Order in Java

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For traversing a linked list in reverse order we can use Descending Iterator or List Iterator

1. Descending Iterator

Syntax:

LinkedList<String> linkedlist = new LinkedList<>();

Iterator<String> listIterator = linkedlist.descendingIterator();

Returns: Descending Iterator returns the Iterator that points to the end of the linked list.

2. List Iterator

Syntax:

LinkedList<String> linkedlist = new LinkedList<>();

ListIterator<String> listIerator = linkedlist.listIterator(linkedlist.size());

Parameter: the size of the linked list, this will make the iterator point at the end of the linked list.

Example 1: Using descending Iterator

Java

// Java program to Iterate a LinkedList in Reverse Order
// using descending Iterator
  
import java.util.Iterator;
import java.util.LinkedList;
  
public class GFG {
    public static void main(String[] args)
    {
        LinkedList<String> linkedList = new LinkedList<>();
        
        // adding elements to linked list
        linkedList.add("Geeks");
        linkedList.add("For");
        linkedList.add("Geek");
        linkedList.add("2020");
        linkedList.add("2021");
  
        // getting an iterator which points at the
        // end of the linkedlist
        Iterator<String> iterator = linkedList.descendingIterator();
  
        // traversing the linkedlist
        // hasNext() will tell if previous element is
        // available or not
        // next() with descending iterator will return the
        // previous element
        // and after getting the previous element
        // is moves the cursor to next previous element.
        while (iterator.hasNext()) 
        {
            System.out.println(iterator.next());
        }
    }
}

Output

2021
2020
Geek
For
Geeks

Example 2: Using List Iterator

Java

// Java program to Iterate a LinkedList in Reverse Order
// using List Iterator
  
import java.util.LinkedList;
import java.util.ListIterator;
  
public class GFG {
    public static void main(String[] args)
    {
  
        LinkedList<String> linkedList = new LinkedList<>();
  
        // adding elements of to the linkedlist
        linkedList.add("Geeks");
        linkedList.add("For");
        linkedList.add("Geek");
        linkedList.add("2020");
        linkedList.add("2021");
  
        // getting an iterator that points at the end of the
        // linkedlist
        ListIterator<String> listIterator = linkedList.listIterator(linkedList.size());
  
        // Traversing the linked list
        // hasPrevious() function to check if previous
        // element is present or not previous() function to
        // get the previous element and after getting
        // previous elements it move the cursor to the next
        // previous element
        while (listIterator.hasPrevious())
        {
            System.out.println(listIterator.previous());
        }
    }
}