Java8 programming, generics, binary tree, implementing an iterator, please explain in detail

Question 7: In-order traversal Once you have completed your binary tree implementation. You will need to implement an iterator that will traverse the binary tree with an in-order traversal. Pseudo-code for an in-order traversal inorder (root): if left_child of root is not null: inorder (left_child) visit (root) if right_child of root is not null: inorder (right_child) It is best that you attempt implement the traversal without using an iterator first so you are familiar with the method, then to transform it to an iterator object where it will maintain state