incompatible types : java.lang.Object cannot be converted to T

Question

Here is my code:

package datastructures;

import java.util.Iterator;

public class Stack{
    private class Node{
        T data;
        N         


        

Answer 1

Node's data field doesn't know it's type.

Try giving the type when you initialize head.

private Node head;
private Node newNode(T data){
    Node new_node = new Node();
    new_node.data = data;
    new_node.next = null;
    return new_node;
}

Now, new_node knows that the data field is of type T.