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package com.zookeeper;import org.apache.zookeeper.*;import org.apache.zookeeper.data.Stat;import org.junit.Before;import org.junit.Test;import java.util.List;/** * @version v1.0 * @Author: huang * @Date: 2020/12/11 */public class ZookeeperDemo {    private static final String CONNECT_STRING = "bigdata01:2181,bigdata02:2181,bigdata03:2181";    private static final int SESSION_TIMEOUT = 2000;    private ZooKeeper zkClient = null;    @Before    public void init() throws Exception {        zkClient = new ZooKeeper(CONNECT_STRING, SESSION_TIMEOUT, new Watcher() {            @Override            public void process(WatchedEvent watchedEvent) {                System.out.println(watchedEvent.getType() + "--" + watchedEvent.getPath());                System.out.println("连接成功");                try {                    zkClient.getChildren("/", true);                } catch (Exception e) {                    e.printStackTrace();                }            }        });    }    @Test    public void create() throws Exception {        String nodeCreated = zkClient.create("/huang", "lan".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        System.out.println(nodeCreated);    }    @Test    public void exist() throws Exception {        Stat stat = zkClient.exists("/atguigu1", false);        System.out.println(stat == null ? "not exist" : "exist");    }    @Test    public void setData() throws Exception {        zkClient.setData("/atguigu1", "jinlian1".getBytes(), 0);    }    @Test    public void getDate() throws Exception {        byte[] zkClientData = zkClient.getData("/atguigu1", null, null);        System.out.println(zkClientData);    }    @Test    public void delete() throws KeeperException, InterruptedException {        zkClient.delete("/atguigu/a1", 1);    }    @Test    public void lsAll() throws Exception {        ls("/");    }    public void ls(String path) throws Exception {        List
   
     list = zkClient.getChildren(path, null);        if (list == null || list.isEmpty()) {            return;        }        for (String s : list) {            if (path.equals("/")) {                ls(path + s);            } else {                ls(path + "/" + s);            }        }    }    @Test    public void watchChange1() throws Exception {        Stat stat = new Stat();        byte[] data = zkClient.getData("/atguigu", new Watcher() {            @Override            public void process(WatchedEvent event) {                if (event.getType() == Event.EventType.NodeDataChanged) {                    System.out.println("节点数据改变了！");                }            }        }, stat);        System.out.println(new String(data));        Thread.sleep(50000);    }    @Test    public void watchChange2() throws Exception {        final Stat stat = new Stat();        final String path = "/atguigu";        byte[] data = zkClient.getData(path, new Watcher() {            @Override            public void process(WatchedEvent event) {                if (event.getType() == Event.EventType.NodeDataChanged) {                    try {                        byte[] res = zkClient.getData(path, this, stat);                        System.out.println("节点数据改变了 " + new String(res));                    } catch (KeeperException | InterruptedException e) {                        e.printStackTrace();                    }                }            }        }, stat);        System.out.println(new String(data));        Thread.sleep(50000);    }    @Test    public void watchDelete() throws Exception {        String path = "/atuguigu/a3";        Stat stat = new Stat();        byte[] data = zkClient.getData(path, new Watcher() {            @Override            public void process(WatchedEvent event) {                if (event.getType() == Event.EventType.NodeDeleted) {                    System.out.println("节点数据删除了！");                }            }        }, stat);        System.out.println("****" + new String(data));        Thread.sleep(Long.MAX_VALUE);    }}