How to print LinkedList Node object in reverse order

Question

In the following method reverse() ,I wanted to access the elements of Node and add them in an ArrayList.After that ,using loop, it will print in reverse order.

public void reverse(){

            Node e = head;
            ArrayList<E> s = new ArrayList<E>();
            while(e!=null){

                s.add(e.element);
                e= e.next;
            }
            for (int i = count-1; i >= 0; i--) {
                System.out.print (""+s.get(i));
            }
            System.out.println("");

    }

But, s.add(e.element) ; is giving an error. Here is Node class,

public class Node<E> {
    E element;
    Node<E> next;

    public Node(E element){
        this.element=element;
        next =null;
    }
}

and LinkedList class

     public class LinkedListStack<E> implements Stack<E>{
            Node<E> head;
            Node<E> tail;
            int count=-1;

            public LinkedListStack() {
               head=tail=null;
            }

     public void push(E element) {
            Node<E> newNode = new Node<>(element);
            if(count==-1){
                head=tail=newNode;
                count++;
            }
            else{
                newNode.next=head;
                head = newNode;
            }
            count++;
        }
             public void reverse(){

                Node e = head;
                ArrayList<E> s = new ArrayList<E>();
                while(e!=null){

                    s.add(e.element);
                    e= e.next;
                }
                for (int i = count-1; i > 1; i--) {
                    System.out.print (""+s.get(i));
                }
                System.out.println("");

            }
}

I will appreciate if someone explains the the error for adding Object

element in the ArrayList in details.

Looks like you have a couple more problems in there as well! You will probably figure them out once you get it printing. — Daniel Nugent, Apr 18 '15 at 16:19
'Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - Erroneous sym type: java.util.ArrayList.add' is the error. - ruben rodriguez fernandez — Shahin Alam, Apr 18 '15 at 16:26

score 2 · Accepted Answer · answered Apr 18 '15 at 16:06

2

You're using the generic Node type as a raw type:

Node e = head;

should be

Node<E> e = head;

answered Apr 18 '15 at 16:06

JB Nizet

678,734
91
1,224
1,255

if I use type casting , does that make any difference than the one you have provided ? – Shahin Alam Apr 18 '15 at 16:23
Generic types exist precisely to allow type-safe code and avoid casts. – JB Nizet Apr 18 '15 at 16:25

How to print LinkedList Node object in reverse order

1 Answers1