public class BinarySearchTree<E extends Comparable<? super E>> extends BinaryTree<E> {

    public BinarySearchTree() {
        super();
    }

    public void add(E value) {
        this.root = this.add(this.root, value);
    }
    private TreeNode<E> add(TreeNode<E> current, E value) {
        if (current == null) {
            return new TreeNode<E>(value, null, null);
        }

        if (value.compareTo(current.getData()) <= 0) {
            current.setLeft(this.add(current.getLeft(), value));
        }
        else {
            current.setRight(this.add(current.getRight(), value));
        }
        return current;
    }


    public boolean contains(E value) {
        return this.contains(this.root, value);
    }
    private boolean contains(TreeNode<E> current, E value) {
        if (current == null) {
            return false;
        }
        else if (value.equals(current.getData())) {
            return true;
        }
        else if (value.compareTo(current.getData()) < 0) {
            return this.contains(current.getLeft(), value);
        }
        else {
            return this.contains(current.getRight(), value);
        }
    }


    public static void main(String[] args) {
        BinarySearchTree<Integer> tree = new BinarySearchTree<Integer>();
        tree.add(7);
        tree.add(2);
        tree.add(12);
        tree.add(1);
        tree.add(5);
        tree.add(6);
        tree.add(99);
        tree.add(88);

        System.out.println(tree);
        System.out.println("size = " + tree.size());
        System.out.println(tree.contains(2) + " " + tree.contains(5)
                                            + " " + tree.contains(8));

        tree.remove(2);
        System.out.println(tree);
        System.out.println("size = " + tree.size());
        System.out.println(tree.contains(2) + " " + tree.contains(5)
                                            + " " + tree.contains(8));
    }
}