The homework requirement is clear that you need an AVL implementation that has insert, remove, traversal.
So hope this could get you started.
public class AVLTreeNode {
private int value;
private AVLTreeNode left;
private AVLTreeNode right;
private AVLTreeNode parent;
//constructor
//getters/setters
//required functions
boolean insert(AVLTreeNode node);
AVLTreeNode remove(int value);
AVLTreeNode remove(AVLTreeNode node);
List<AVLTreeNode> inorderTraversal();
}