如何在Java单向链表中实现append方法？

public class LinkedList {

    private Node head;

    private static class Node {
        int data;
        Node next;

        Node(int data) {
            this.data = data;
            this.next = null;
        }
    }

    public LinkedList() {
        this.head = null;
    }

    // Append method
    public void append(LinkedList list) {
        if (list == null || list.head == null) {
            return; // Nothing to append
        }

        if (head == null) {
            head = list.head;
            return;
        }

        Node current = head;
        while (current.next != null) {
            current = current.next;
        }

        current.next = list.head;
    }

    // Method to insert a new node
    public void push(int new_data)
    {
        Node new_node = new Node(new_data);
        new_node.next = head;
        head = new_node;
    }

    // Method to print the LinkedList.
    public void printList()
    {
        Node tnode = head;
        while (tnode != null) {
            System.out.print(tnode.data + " ");
            tnode = tnode.next;
        }
    }


    public static void main(String[] args) {
        LinkedList list1 = new LinkedList();
        list1.push(2);
        list1.push(1);
        list1.push(0);

        LinkedList list2 = new LinkedList();
        list2.push('B');
        list2.push('A');


        System.out.println("List1 before append:");
        list1.printList();

        System.out.println("\nList2 before append:");
        list2.printList();

        list1.append(list2);

        System.out.println("\nList1 after append:");
        list1.printList();
    }
}