二叉树

package muke.binarytree;/** * Created by jc6a on 2017/8/31. */public class Node<T extends Comparable> implements Comparable<Node<T>>{    private T data;    private Node leftNode;    private Node righNode;    public Node( T t ){        this(t,null,null);    }    public  Node(T t,Node<T> leftNode,Node<T> rightNode){        this.data = t;        this.leftNode = leftNode;        this.righNode = rightNode;    }    @Override    public int compareTo(Node<T> o) {        return data.compareTo(o.data);    }    public T getData() {        return data;    }    public void setData(T data) {        this.data = data;    }    public Node getLeftNode() {        return leftNode;    }    public void setLeftNode(Node leftNode) {        this.leftNode = leftNode;    }    public Node getRighNode() {        return righNode;    }    public void setRighNode(Node righNode) {        this.righNode = righNode;    }    @Override    public String toString() {        return "Node{" +                "data=" + data +                ", leftNode=" + leftNode +                ", righNode=" + righNode +                '}';    }}

package muke.binarytree;/** * Created by jc6a on 2017/8/31. */public class Tree {    public Node root;    public <T> Node search(T key){        if(null == root) return null;        Node node = root;        while(null!= node){            int compareResult = node.getData().compareTo(key);            if(compareResult>0){                node = node.getRighNode();            }else if(compareResult<0){                node = node.getLeftNode();            }else{                break;            }        }        return node;    }    public <T extends Comparable> void insert(T key){        Node node = new Node(key);        if(root == null){            root = node;        }else{            Node currentNode = root;            boolean isLeftNode = true;            while(currentNode != null){                int compareResult = currentNode.compareTo(node);                if(compareResult>0){                    isLeftNode = true;                    if(currentNode.getLeftNode()==null) break;                    currentNode = currentNode.getLeftNode();                }else if(compareResult<0){                    isLeftNode = false;                    if(currentNode.getRighNode()==null) break;                    currentNode = currentNode.getRighNode();                }else{                    return;                }            }            if(isLeftNode){                currentNode.setLeftNode(node);            }else{                currentNode.setRighNode(node);            }        }    }    public <T extends Comparable> boolean delete(T key){        Node currentNode = root;        Node parent = root;        Node node = new Node(key);        int compareResult;        boolean isLeftNode = true;        while(null!=currentNode&&(compareResult = currentNode.compareTo(node))!=0){            parent = currentNode;            if(compareResult>0){                currentNode = currentNode.getLeftNode();            }else{                isLeftNode = false;                currentNode = currentNode.getRighNode();            }        }        if(null == currentNode) return false;        //要删除的节点没有子节点        if(currentNode.getLeftNode() == null && currentNode.getRighNode() == null){            if(currentNode == root){                root = null;            }else if(isLeftNode){                parent.setLeftNode(null);            }else{                parent.setRighNode(null);            }        }        //要删除的节点只有右节点        else if(currentNode.getLeftNode() == null){            if(currentNode == root){                root = currentNode.getRighNode();            }else if(isLeftNode){                parent.setLeftNode(currentNode.getRighNode());            }else{                parent.setRighNode(currentNode.getRighNode());            }        }        //要删除的节点只有左节点        else if(currentNode.getRighNode() == null){            if(currentNode == root){                root = currentNode.getLeftNode();            }else if(isLeftNode){                parent.setLeftNode(currentNode.getLeftNode());            }else{                parent.setRighNode(currentNode.getLeftNode());            }        }        //要删除的节点有两个节点        else{            Node successor = findSuccessor(currentNode);            if(currentNode == root){                root = successor;            }else if(isLeftNode){                parent.setLeftNode(successor);            }else {                parent.setRighNode(successor);            }            successor.setLeftNode(currentNode.getLeftNode());        }        return true;    }    public Node findSuccessor(Node node){        Node parent = node;        Node successsor = node;        Node current = node.getRighNode();        while(current!=null){            parent = successsor;            successsor = current;            current = current.getLeftNode();        }        if(successsor != node.getRighNode()){            parent.setLeftNode(successsor.getRighNode());            successsor.setRighNode(node.getRighNode());        }        return successsor;    }    public static void main(String[] args) {        Tree tree = new Tree();        tree.insert(6);        tree.insert(2);        tree.insert(4);        tree.insert(3);        tree.insert(1);        tree.insert(5);        tree.insert(8);        System.out.println(tree.root);        tree.delete(2);        System.out.println(tree.root);        //                6        //               /  \        //              2    8        //             / \        //            1   4        //                / \        //               3   5    }}