Java实现二叉搜索树

/**
 * 二叉搜索树
 */
public class BinaryTree implements ITree<BinaryTree.Node> {

    public Node root;

    public BinaryTree() {
    }

    /**
     * 插入
     *
     * @param data
     * @return
     */
    @Override
    public boolean insert(int data) {
        if (root == null) {
            root = new Node(data);
            return true;
        }else {
            Node newNode = new Node(data);
            Node current = root;
            Node parentNode;
            while (current != null) {
                parentNode = current;
                if (current.data > data) {
                    current = current.leftNode;
                    if (current == null) {
                        parentNode.leftNode = newNode;
                        return true;
                    }
                } else {
                    current = current.rightNode;
                    if (current == null) {
                        parentNode.rightNode = newNode;
                        return true;
                    }
                }
            }

        }

        return false;
    }

    /**
     * 先序遍历
     *
     * @param node
     */
    @Override
    public void preOrder(Node node) {
        if (node != null) {
            System.out.println(node.data);
            preOrder(node.leftNode);
            preOrder(node.rightNode);
        }


    }

    /**
     * 中序遍历
     *
     * @param node
     */
    @Override
    public void infixOrder(Node node) {
        if (node != null) {
            infixOrder(node.leftNode);
            System.out.println(node.data);
            infixOrder(node.rightNode);
        }
    }

    /**
     * 后序遍历
     *
     * @return
     */
    @Override
    public void postOrder(Node node) {
        if (node != null) {
            infixOrder(node.leftNode);
            infixOrder(node.rightNode);
            System.out.println(node.data);
        }
    }


    /**
     * 查找最大值
     *
     * @return
     */
    @Override
    public Object findMax() {
        Node current = root;
        if (current != null && current.rightNode != null) {
            current = current.rightNode;
        }
        return current;
    }

    /**
     * 查找最小值
     *
     * @return
     */
    @Override
    public Object findMin() {
        Node current = root;
        if (current != null && current.leftNode != null) {
            current = current.leftNode;
        }
        return current;
    }

    /**
     * 删除节点
     *
     * @param data
     */
    @Override
    public void delete(Node data) {

    }

    static class Node {
        int data;
        Node leftNode;
        Node rightNode;

        public Node(int data) {
            this.data = data;
        }
    }
}