I NEED findSize() WRITTEN IN JAVA

The following questions deal with Binary Search Tree. All the nodes of the Binary Search Tree are defined using the following class: class Node {public int Key; public String Value; public Node Right; public Node Left;} (a) Insert items with the following keys (in the given order) into an initially empty binary search tree: 50, 40, 30, 46, 38, 58, 56, 52. Draw the tree after you have inserted all items (just show the key of each node). (b) Write a method findSize() that returns the total number of nodes in an arbitrary binary search tree. Please indicate the complexity of your method in big-O notation