package com.zhengmo.test;

import java.util.List;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.ZooDefs.Ids;

import org.apache.zookeeper.ZooKeeper;

/**

 * @author zhengmo

 */

public class ZkMove {

    private static int deleteCount = 0;

    private static int moveCount = 0;

    public static void main(String[] args) throws Exception {

        //

        //旧zk服务器

        ZooKeeper oldzk = new ZooKeeper("192.168.1.112:2181", 60000, null);

        //新zk服务器

        ZooKeeper newzk = new ZooKeeper("172.17.32.105:2181", 60000, null);

        //需要迁移的节点

        String node = "/dubbo";

        //删除指定节点

        delete(newzk, node);

        System.out.println("删除节点数:" + deleteCount);

        //获取节点下的一级子节点

        List<String> children = oldzk.getChildren(node, false);

        move(oldzk, newzk, children, node);

        System.out.println("移动节点数:" + moveCount);

        oldzk.close();

        newzk.close();

    }

    /**

     * 递归删除指定节点的子节点.

     * @param newzk zk

     * @param node 节点

     * @return 成功否

     * @throws Exception 异常

     */

    private static boolean delete(ZooKeeper newzk, String node) throws Exception {

        List<String> children = newzk.getChildren(node, false);

        if (children == null || children.size() == 0) {

            //System.out.println("delete node:" + node);

            newzk.delete(node, -1);

            deleteCount++;

            return true;

        } else {

            for (String child : children) {

                while (!delete(newzk, node + "/" + child)) {

                }

            }

            return false;

        }

    }

    /**

     * 移动指定zk1的指定节点到指定zk2的节点下.

     * @param oldzk 旧zk

     * @param newzk 新zk

     * @param children 子节点

     * @param parent 父节点

     * @throws KeeperException 异常

     * @throws InterruptedException 异常

     */

    private static void move(ZooKeeper oldzk, ZooKeeper newzk, List<String> children, String parent) throws KeeperException, InterruptedException {

        if (newzk.exists(parent, false) == null) {

            newzk.create(parent, null, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

            System.out.println("create " + parent);

        }

        if (children == null || children.isEmpty()) {

            return;

        } else {

            for (String child : children) {

                String c = parent + "/" + child;

                //System.out.println(c);

                byte[] data = oldzk.getData(c, false, null);

                if (newzk.exists(c, false) == null) {

                    newzk.create(c, data, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

                    moveCount++;

                } else {

                    newzk.setData(c, data, -1, null, null);

                    moveCount++;

                }

                //递归移动

                move(oldzk, newzk, oldzk.getChildren(c, false), c);

            }

        }

    }

}