On the code which defines a node class whose elements are Comparable.

On the code which defines a node class whose elements are Comparable. Complete the validBST() method so that it returns true when instance defines a subtree that is a valid BST; and false when the subtree violates the definition of how a BST is ordered.

Code:

package edu.buffalo.cse116;

public class BSTNode<E extends Comparable<E>> { /** Tree's element which is stored within this Node. */ protected E element; /** Left child of the current Node. */ protected BSTNode<E> left; /** Right child of the current Node. */ protected BSTNode<E> right; /** Parent in the binary tree for the current Node. */ protected BSTNode<E> parent; /*** Creates a new BSTNode object with the specified element and parent BSTNode.** @param element Data to be held in this BSTNode.* @param parent Parent for this entry within the binary tree.*/ public BSTNode(E element, BSTNode<E> parent) {this.element = element;this.parent = parent; } /*** Validates whether the subtree rooted at this BSTNode is a valid binary search tree.** @return True if the elements within this subtree are legally organized following BST rules; false otherwise.*/ public boolean validBST() { }}