LinkedList imps

package linked_list_implementation;

public class LinkedList<T> {

    private Node<T> head = null;

    void add(T element) {
        Node<T> node  = new Node<>(element);
        if(head == null) {
            head = node;
        }
        else {
            Node<T> curr = head;
            while(curr.next != null) {
                curr = curr.next;
            }
            curr.next = node;
        }
    }

    void addFirst(T element) {
        Node<T> node  = new Node<>(element);
        if(head == null) head = node;
        else{
            Node<T> curr  = head;
            Node<T> res = node;
            while(curr != null) {
                node.next = curr;
                curr = curr.next;
                node = node.next;
            }
            head = res;
        }
    }

    T poll() {
        if(head == null) return null;
        Node<T> first = head;
        head = head.next;
        return first.val;
    }

    boolean remove(T element) {
        if(head == null) return false;
        if (head.next == null && head.val == element) {
            head = null;
            return true;
        }
        Node<T> curr = head;
        Node<T> prev = null;
        while(curr != null && curr.val != element) {
            prev = curr;
            curr = curr.next;
        }
        if (curr == null) return false;

        assert prev != null;
        prev.next = curr.next;

        return true;
    }

    @Override
    public String toString() {
        return "LinkedList{" +
                "head=" + head +
                '}';
    }

    private static class Node<T> {
        T val;
        Node<T> next;

        public Node(T val) {
            this.val = val;
        }

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

        @Override
        public String toString() {
            return "Node{" +
                    "val=" + val +
                    ", next=" + next +
                    '}';
        }
    }
}