Java program to implement Binary Search Tree

public class Binary{
	public static Node root;
	public BinarySearchTree(){
	this.root = null;
	}
	public boolean find(int id){
	Node current = root;
	while(current!=null){
	if(current.data==id){
	return true;
	}else if(current.data>id){
	current = current.left;
	}else{
	current = current.right;
	}
	}
	return false;
	}
	public boolean delete(int id){
	Node parent = root;
	Node current = root;
	boolean isLeftChild = false;
	while(current.data!=id){
	parent = current;
	if(current.data>id){
	isLeftChild = true;
	current = current.left;
	}else{
	isLeftChild = false;
	current = current.right;
	}
	if(current ==null){
	return false;
	}
	}
	//if i am here that means we have found the node
	//Case 1: if node to be deleted has no children
	if(current.left==null && current.right==null){
	if(current==root){
	root = null;
	}
	if(isLeftChild ==true){
	parent.left = null;
	}else{
	parent.right = null;
	}
	}
	//Case 2 : if node to be deleted has only one child
	else if(current.right==null){
	if(current==root){
	root = current.left;
	}else if(isLeftChild){
	parent.left = current.left;
	}else{
	parent.right = current.left;
	}
	}
	else if(current.left==null){
	if(current==root){
	root = current.right;
	}else if(isLeftChild){
	parent.left = current.right;
	}else{
	parent.right = current.right;
	}
	}else if(current.left!=null && current.right!=null){
	//now we have found the minimum element in the right sub tree
	Node successor = getSuccessor(current);
	if(current==root){
	root = successor;
	}else if(isLeftChild){
	parent.left = successor;
	}else{
	parent.right = successor;
	}
	successor.left = current.left;
	}
	return true;
	}
	public Node getSuccessor(Node deleleNode){
	Node successsor =null;
	Node successsorParent =null;
	Node current = deleleNode.right;
	while(current!=null){
	successsorParent = successsor;
	successsor = current;
	current = current.left;
	}
	//check if successor has the right child, it cannot have left child for sure
	// if it does have the right child, add it to the left of successorParent.
	// successsorParent
	if(successsor!=deleleNode.right){
	successsorParent.left = successsor.right;
	successsor.right = deleleNode.right;
	}
	return successsor;
	}
	public void insert(int id){
	Node newNode = new Node(id);
	if(root==null){
	root = newNode;
	return;
	}
	Node current = root;
	Node parent = null;
	while(true){
	parent = current;
	if(id<current.data){
	current = current.left;
	if(current==null){
	parent.left = newNode;
	return;
	}
	}else{
	current = current.right;
	if(current==null){
	parent.right = newNode;
	return;
	}
	}
	}
	}
	public void display(Node root){
	if(root!=null){
	display(root.left);
	System.out.print(" " + root.data);
	display(root.right);
	}
	}
	public static void main(String arg[]){
	BinarySearchTree b = new BinarySearchTree();
	b.insert(3);b.insert(8);
	b.insert(1);b.insert(4);b.insert(6);b.insert(2);b.insert(10);b.insert(9);
	b.insert(20);b.insert(25);b.insert(15);b.insert(16);
	System.out.println("Original Tree : ");
	b.display(b.root);
	System.out.println("");
	System.out.println("Check whether Node with value 4 exists : " + b.find(4));
	System.out.println("Delete Node with no children (2) : " + b.delete(2));
	b.display(root);
	System.out.println("\n Delete Node with one child (4) : " + b.delete(4));
	b.display(root);
	System.out.println("\n Delete Node with Two children (10) : " + b.delete(10));
	b.display(root);
	}
	}
	class Node{
	int data;
	Node left;
	Node right;
	public Node(int data){
	this.data = data;
	left = null;
	right = null;
	} }