هل يمكن شرح هذا الكود؟ و هل هناك طريقة أفضل لعمل BinarySearchTree؟

public class BinaryTree2 {
    class Node
    {
        int key;
        Node left, right;

        public Node(int item)
        {
            key = item;
            left = right = null;
        }
    }

    // Root of BST
    Node root;

    // Constructor
    BinaryTree2()
    {
        root = null;
    }

    void deleteKey(int key)
    {
       root = deleteRec(root, key);
    }

    Node deleteRec(Node root, int key)
    {
        /* Base Case: If the tree is empty */
        if (root == null)
            return root;

        /* Otherwise, recur down the tree */
        if (key < root.key)
            root.left = deleteRec(root.left, key);
        else if (key > root.key)
            root.right = deleteRec(root.right, key);

            // if key is same as root's
            // key, then This is the
            // node to be deleted
        else {
            // node with only one child or no child
            if (root.left == null)
                return root.right;
            else if (root.right == null)
                return root.left;

            // node with two children: Get the inorder
            // successor (smallest in the right subtree)
            root.key = minValue(root.right);

            // Delete the inorder successor
            root.right = deleteRec(root.right, root.key);
        }

        return root;
    }

    int minValue(Node root)
    {
        int minv = root.key;
        while (root.left != null)
        {
            minv = root.left.key;
            root = root.left;
        }
        return minv;
    }

    // This method mainly calls insertRec()
    void insert(int key)
    {
        root = insertRec(root, key);
    }

    /* A recursive function to
       insert a new key in BST */
    Node insertRec(Node root, int key)
    {

        /* If the tree is empty,
           return a new node */
        if (root == null)
        {
            root = new Node(key);
            return root;
        }

        /* Otherwise, recur down the tree */
        if (key < root.key)
            root.left = insertRec(root.left, key);
        else if (key > root.key)
            root.right = insertRec(root.right, key);

        /* return the (unchanged) node pointer */
        return root;
    }

    // This method mainly calls InorderRec()
    void inorder()
    {
        inorderRec(root);
    }

    // A utility function to
    // do inorder traversal of BST
    void inorderRec(Node root)
    {
        if (root != null) {
            inorderRec(root.left);
            System.out.println(root.key);
            inorderRec(root.right);
        }
    }
}