Why type error when using Generic?

Question

Java

I'm learning Java and algorithms along the way, I ran into an error, help me figure it out
. I'm passing the desired type to the class, what's the problem?

class Node<T> {

    T element;
    Node<T> next;

    public Node(T element, Node<T> next) {
        this.element = element;
        this.next = next;
    }
}

public class LinkedList<T> {

    Node<T> head;

    public LinkedList(Node<T> head) {
        this.head = head;
    }

    public T getValueById(Number id) {
        Number counter = 0;
        Node<T> searchingNode = this.head;

        while (id != counter) {
            searchingNode = searchingNode.next;

            if (searchingNode == null) {
                return -1; // Здесь ошибка Required type: T; Provided: int
            }
        }

        return searchingNode.element;
    }
    
}


public class Main {

    public static void main(String[] args) {

        Node<Integer> head = new Node(10, null);
        LinkedList<Integer> list = new LinkedList(head);

        System.out.print(list.getValueById(0));
    }
}

Answer 1

You return 1, which is an int, but you promise that the function will return type T.
Return null or return Object