How would we validate BST in Java? ```javaimport java.util.*;public class BSTChecker { public static Node checkBSTValidity(Node rootNode) { // Your code here (remove the placeholder line below) return rootNode; }}```**Explanation of Code:**This Java code snippet defines a class named `BSTChecker` intended for checking the validity of a Binary Search Tree (BST). Let's break it down:1. **Import Statement:** - `import java.util.*;`: This line imports all the utilities from the Java Utility package, which provides essential classes like lists, arrays, and data structures.2. **Class Definition:** - `public class BSTChecker`: This declares a public class named `BSTChecker`. Being public means it can be accessed from any other class.3. **Method Definition:** - `public static Node checkBSTValidity(Node rootNode)`: - This method is intended to check the validity of a BST starting from a given `rootNode`. - It is a static method, meaning it can be called without creating an instance of the `BSTChecker` class. - The method expects an argument of type `Node` named `rootNode` and returns a `Node` object.4. **TODO Comment:** - `// Your code here (remove the placeholder line below)`: This comment indicates where the actual logic to check the BST validity should be implemented.5. **Return Statement:** - `return rootNode;`: Currently, this method simply returns the rootNode object without performing any checks. This is a placeholder behavior and should be replaced with proper BST validation logic.

Binary search tree: A binary Search Tree is a data structure that is based on a binary tree and is composed of nodes. It possesses the following properties: There are no nodes in a node's left subtree that have keys that are greater than the key of the node itself. Only nodes with keys that are higher than the key of a given node can be found in that node's right subtree. In addition, both the left and right subtrees have to be structured as binary search trees. It is imperative that there be no duplicate nodes. When arranging the components, a binary search tree will follow some kind of order. The value of the left node in a Binary search tree must be less than the value of the parent node, and the value of the right node must be greater than the value of the parent node. Recursively, this rule is applied to the left and right subtrees of the root. As seen in the illustration to the right, the root node has a value of 40; all of the nodes on the left subtree have a value that is less than or equal to the root node; and all of the nodes on the right subtree have a value that is equal to or greater than the root node. In a similar manner, we are able to observe that the left child of the root node has a bigger value than its left child but a lower value than its right child. Therefore, it meets the requirements of the binary search tree attribute as well. Because of this, we are able to identify the tree in the above picture as a binary search tree. Check to see whether the tree will still be a binary search tree if the value of node 35 is changed to 55 in the previous example. The value of the root node in the tree shown above is 40, which is lower than the value of its left child 30, which is 55, but higher than the value of its right child 30, which is also 40. , the aforementioned tree does not fulfil the requirements for a Binary search tree. As a result, the tree that was shown before is not a binary search tree.