Java Method isn't resolved by stack object

Question

I was trying to solve a problem named push at bottom of stack. I got the recursion logic but the thing is, I have written a method pushAtbottom but the method is not recognized by the main method and I don't understand why. The error is 'Can not resolve pushAtbottom'

import java.util.Stack;

public class pushatbottom {

    public static void main(String[] args) {

        Stack<Integer> s =new Stack<>();

        s.push(1);
        s.push(2);
        s.push(3);
        s.push(4);
        s.push(5);
        s.pushAtbottom(6,s);
        while(!s.isEmpty())
        {
            System.out.println(s.peek());
            s.pop();
        }
    }

    void pushAtbottom(int data,Stack<Integer> s)
    {
        if(s.isEmpty())
        {
            s.push(data);
        }
        int top=s.pop();
        pushAtbottom(4,s);
        s.push(top);

    }
}

Answer 1

pushAtbottom is a method of your class, not of java.util.Stack . You need to declare it as static (ie, static void ushAtbottom(int data,Stack<Integer> s) ) and then pass the stack to it when calling it form main :

pushAtbottom(6, s);