ZooKeeper 基本操作 与 Java APIs
2024-04-12 15:11:38
前言
在前章ZooKeeper安装(集群化)我们安装ZooKeeper集群. 本章, 我们讲解下ZooKeeper的基本操作.
命令行操作
我们通常使用zkCli.sh脚本进行登陆.登陆命令:./zkCli.sh --server 192.168.31.60:2181
其后,基本操作主要有如下几种:
- help命令
显示客户所支持的所有命令，如：
[zk: 192.168.31.60:2181(CONNECTED) 2] h
ZooKeeper -server host:port cmd argsstat path [watch]set path data [version]ls path [watch]delquota [-n|-b] pathls2 path [watch]setAcl path aclsetquota -n|-b val pathhistoryredo cmdnoprintwatches on|offdelete path [version]sync pathlistquota pathrmr pathget path [watch]create [-s] [-e] path data acladdauth scheme authquitgetAcl pathcloseconnect host:port
其中, 用的比较多的有create/ls/delete/set/close/rmr.
create [-s] [-e] path data acl-s为顺序充点，-e临时节点
例如:create /servers/hello/1 "123" world:anyone:cdrwa需要特别注意的是,创建的父结点需要存在.否则会创建失败.
# 失败
[zk: 192.168.31.60:2181(CONNECTED) 7] create /servers/hello/1 ""
Node does not exist: /servers/hello/1
# 成功
[zk: 192.168.31.60:2181(CONNECTED) 13] create /servers/hello "123" world:anyone:cdrwa
Created /servers/hello
ls path [watch]其中[watch]相当于观察者.回调函数.
[zk: 192.168.31.60:2181(CONNECTED) 17] ls /servers
[hello]
delete path [version]删除单个结点.注意不能循环删除.(即/servers/hello无法直接删除父亲结点/servers,需要先删除子结点再删除父结点. )
# 删除失败
[zk: 192.168.31.60:2181(CONNECTED) 15] delete /servers
Node not empty: /servers
# 删除成功
[zk: 192.168.31.60:2181(CONNECTED) 19] delete /servers/hello/1
[zk: 192.168.31.60:2181(CONNECTED) 20] delete /servers/hello
[zk: 192.168.31.60:2181(CONNECTED) 22] delete /servers
set path data [version]与get path [watch]: 设置结点 / 获得结点
[zk: 192.168.31.60:2181(CONNECTED) 25] get /servers
"123"
cZxid = 0x30000000d
ctime = Sat Mar 23 06:26:54 PDT 2019
mZxid = 0x30000000d
mtime = Sat Mar 23 06:26:54 PDT 2019
pZxid = 0x30000000d
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 0
[zk: 192.168.31.60:2181(CONNECTED) 26] set /servers "456"
cZxid = 0x30000000d
ctime = Sat Mar 23 06:26:54 PDT 2019
mZxid = 0x30000000e
mtime = Sat Mar 23 06:27:19 PDT 2019
pZxid = 0x30000000d
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 0
[zk: 192.168.31.60:2181(CONNECTED) 27] get /servers
"456"
cZxid = 0x30000000d
ctime = Sat Mar 23 06:26:54 PDT 2019
mZxid = 0x30000000e
mtime = Sat Mar 23 06:27:19 PDT 2019
pZxid = 0x30000000d
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 0
rmr path强制删除.可以级联删除.
[zk: 192.168.31.60:2181(CONNECTED) 29] rmr /servers
history查看历史命令
[zk: 192.168.31.60:2181(CONNECTED) 30] history
20 - delete /servers/hello
21 - delete /servers/
22 - delete /servers
23 - ls
24 - create /servers "123"
25 - get /servers
26 - set /servers "456"
27 - get /servers
28 - rmr servers
29 - rmr /servers
30 - history
stat查看结点信息
[zk: 192.168.31.60:2181(CONNECTED) 32] stat /servers
cZxid = 0x300000010
ctime = Sat Mar 23 06:29:53 PDT 2019
mZxid = 0x300000010
mtime = Sat Mar 23 06:29:53 PDT 2019
pZxid = 0x300000010
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 0
close: 断开客户端与服务端的连接.ls2:ls的扩展,多显示一层.setquota设置子结点配额.
# 设置/zookeeper/node子节点个数最大为4
[zk: 192.168.31.60:2181(CONNECTED) 39] setquota -n 4 /servers
Comment: the parts are option -n val 4 path /servers
# 设置/zookeeper/node节点长度最大为100
setquota –b 100 /zookeeper/node
[zk: 192.168.31.60:2181(CONNECTED) 40] setquota -b 100 /servers
Comment: the parts are option -b val 100 path /servers
Command failed: java.lang.IllegalArgumentException: /servers has a parent /zookeeper/quota/servers which has a quota
# 貌似只能选择其一
delquota删除配额. -n为子节点个数, -b为节点数据长度.如delquota –n 2.listquota显示配额.没有配置则显示为空.
# 不显示
[zk: 192.168.31.60:2181(CONNECTED) 41] listquota /servers/hello
absolute path is /zookeeper/quota/servers/hello/zookeeper_limits
quota for /servers/hello does not exist.
# 显示
[zk: 192.168.31.60:2181(CONNECTED) 42] listquota /servers
absolute path is /zookeeper/quota/servers/zookeeper_limits
Output quota for /servers count=4,bytes=-1
Output stat for /servers count=2,bytes=18
printwatches: 设置和显示监视状态,on或者off.printwatches onsync: 强制同步. 如sync /servers. 由于请求在半数以上的zk server上生效就表示此请求生效, 那么就会有一些zk server上的数据是旧的. sync命令就是强制同步所有的更新操作.(即所有的都更新完毕后,再进行其他操作.)redo: 再次执行某命令. 如redo 10. 其中10为命令ID，需与history配合使用。
setAcl命令: 设置节点Acl.此处重点说一下acl，acl由大部分组成：1为scheme，2为user，3为permission，一般情况下表示为scheme?permissions。
其中scheme和id是相关的，下面将scheme和id一起说明。
- scheme和id
world: 它下面只有一个id, 叫anyone, world:anyone代表任何人，zookeeper中对>所有人有权限的结点就是属于world:anyone的.- auth: 它不需要id, 只要是通过authentication的user都有权限（zookeeper支持通过kerberos来进行authencation, 也支持username/password形式的authentication)
- digest: 它对应的id为username:BASE64(SHA1(password))，它需要先通过username:password形式的authentication
- ip: 它对应的id为客户机的IP地址，设置的时候可以设置一个ip段，比如ip:192.168.1.0/16, 表示匹配前16个bit的IP段
super: 在这种scheme情况下，对应的id拥有超级权限，可以做任何事情(cdrwa)- permissions
CREATE©: 创建权限，可以在在当前node下创建child node
DELETE(d): 删除权限，可以删除当前的node
READ®: 读权限，可以获取当前node的数据，可以list当前node所有的child nodes
WRITE(w): 写权限，可以向当前node写数据
ADMIN(a): 管理权限，可以设置当前node的permission
综上，一个简单使用setAcl命令，则可以为：
setAcl /zookeeper/node1 world:anyone:cdrwgetAcl: 获取节点Acl。如getAcl /zookeeper/node1 'world,'anyone : cdrwa注：可参见setAcl命令。
addauth: 节点认证。
如addauth digest username:password，可参见setAcl命令digest处。
使用方法：
一、通过setAcl设置用户名和密码setAcl pathdigest:username:base64(sha1(password)):crwda
二、认证
addauth digest username:password
Java API
ZooKeeper提供的API主要使用的有:
ZooKeeper
ZKClient
Cursor
三种包的使用有点不太相同.但是都是基于命令行的形式,完成了它们各自的API. 主要提供都API:皆为zkClient()/create()/delete()/exists()/getChildren()等等.ZooKeeper
<!-- ZK Dependence --><dependency><groupId>org.apache.zookeeper</groupId><artifactId>zookeeper</artifactId><version>3.4.6</version></dependency>
OriginZooKeeperAPIs
import org.apache.zookeeper.*;
import org.apache.zookeeper.data.Stat;import java.io.IOException;
import java.util.List;public class OriginZooKeeperAPIs {private static String connStr = "192.168.31.60:2181,192.168.31.61:2181,192.168.31.62:2181";private static int timeout = 2000;private static ZooKeeper zooKeeper = null;//建立客户端连接public static void init() throws IOException {zooKeeper = new ZooKeeper(connStr, timeout, new Watcher() {@Overridepublic void process(WatchedEvent watchedEvent) {System.out.println(watchedEvent.getType()+" --- " + watchedEvent.getPath());try {zooKeeper.getChildren("/",true);} catch (KeeperException e) {e.printStackTrace();} catch (InterruptedException e) {e.printStackTrace();}}});}public static void main(String[] args) throws IOException, KeeperException, InterruptedException {init();
// createNode();
// exist();
// getChildren();
// deleteNode();
// exist();getData();}//创建节点public static void createNode() throws KeeperException, InterruptedException {String s = zooKeeper.create("/sean", "zs".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);System.out.println(s);}//判断节点是否存在public static void exist() throws KeeperException, InterruptedException {Stat stat = zooKeeper.exists("/sean", false);System.out.println(stat==null?"not exist":"exist");}//获取子节点public static void getChildren() throws KeeperException, InterruptedException {List<String> children = zooKeeper.getChildren("/", true);children.stream().forEach(child -> System.out.println(child));Thread.sleep(Long.MAX_VALUE);}//删除public static void deleteNode() throws KeeperException, InterruptedException {zooKeeper.delete("/sean",-1);}//获取节点数据public static void getData() throws KeeperException, InterruptedException {byte[] data = zooKeeper.getData("/sean", true, null);System.out.println(new String(data));}//更改节点数据public static void setData() throws KeeperException, InterruptedException {zooKeeper.setData("/sean","sean".getBytes(),2);}}
- ZKClient
<!-- ZK Dependence --><dependency><groupId>org.apache.zookeeper</groupId><artifactId>zookeeper</artifactId><version>3.4.6</version></dependency> <dependency><groupId>com.101tec</groupId><artifactId>zkclient</artifactId><version>0.5</version></dependency>
OriginalClientAPIs
package com.yanxml.zookeeper.original.zkclient;import java.util.List;import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.serialize.SerializableSerializer;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.data.Stat;import com.yanxml.zookeeper.business.User;
import com.yanxml.zookeeper.config.ZooKeeperConfig;public class OriginalClientAPIs {// 获取ZooKeeper客户端public ZkClient getClient() {ZkClient zkClient = null;zkClient = new ZkClient(ZooKeeperConfig.ZOOURLS, 10000, 10000,new SerializableSerializer());return zkClient;}// 创建一个节点&创建节点的子节点public String createZkNode(ZkClient zkClient) {String path = "";if (null != zkClient) {if (!zkClient.exists("/user")) {User user = new User("Sean", 24);path = zkClient.create("/user", user, CreateMode.PERSISTENT);// log.warn}// 创建子节点if (!zkClient.exists("/user/petter")) {User user = new User("Petter", 24);path = zkClient.create("/user/petter", user,CreateMode.PERSISTENT);}// 创建子节点if (!zkClient.exists("/user/bruce")) {User user = new User("Bruce", 24);path = zkClient.create("/user/bruce", user,CreateMode.PERSISTENT);}// 创建子子节点if (!zkClient.exists("/user/bruce/abel")) {User user = new User("Abel", 24);path = zkClient.create("/user/bruce/abel", user,CreateMode.PERSISTENT);}}return path;}// 获取一个节点public Object getZkNode(ZkClient zkClient) {User user = null;if (null != zkClient) {Stat stat = new Stat();user = zkClient.readData("/user", stat);System.out.println("user:" + user.toString() + " stat:" + stat.toString());return user;}return user;}// 获取子节点(只向下获取一层 儿子的儿子节点不会获取)public List<String> getChildZkNode(ZkClient zkClient) {List<String> resultObj = null;if (null != zkClient) {resultObj = zkClient.getChildren("/user");System.out.println("Children String List: " + resultObj);}return resultObj;}// 查询节点是否存在public boolean existZkNode(ZkClient zkClient) {boolean flag = false;if (null != zkClient) {flag = zkClient.exists("/user");System.out.println("Node Exists: " + " '/user' " + flag);}return flag;}// 删除&循环删除public boolean deleteZkNode(ZkClient zkClient) {boolean flag = false;if (null != zkClient) {// 单节点删除(当存在子节点时候 会出现删除失败的情况)// flag = zkClient.delete("/user");// System.out.println("Delete OK " + " '/user' " + flag);// 循环删除flag = zkClient.deleteRecursive("/user");System.out.println("Recursive delete OK " + " '/user' " + flag);}return flag;}// 修改节点内容public boolean updateZkNode(ZkClient zkClient){boolean flag = false;if( null != zkClient){if(zkClient.exists("/user")){User user = new User("ChiGua", 24);zkClient.writeData("/user", user);}}return flag;}public static void main(String[] args) {OriginalClientAPIs apisDemo = new OriginalClientAPIs();// 获取client端ZkClient zkClient = apisDemo.getClient();// 创建节点apisDemo.createZkNode(zkClient);// 获取节点apisDemo.getZkNode(zkClient);// 获取从节点 地址apisDemo.getChildZkNode(zkClient);// apisDemo.existZkNode(zkClient);// apisDemo.deleteZkNode(zkClient);apisDemo.updateZkNode(zkClient);}}// Bug1:创建 原节点已经存在 创建失败// Bug2:节点包含子节点 删除失败
// Exception in thread "main" org.I0Itec.zkclient.exception.ZkException:
// org.apache.zookeeper.KeeperException$NotEmptyException: KeeperErrorCode =
// Directory not empty for /user
// at org.I0Itec.zkclient.exception.ZkException.create(ZkException.java:68)
// at org.I0Itec.zkclient.ZkClient.retryUntilConnected(ZkClient.java:893)
// at org.I0Itec.zkclient.ZkClient.delete(ZkClient.java:936)
// at
// com.yanxml.zookeeper.original.zkclient.OriginalClientAPIs.deleteZkNode(OriginalClientAPIs.java:84)
// at
// com.yanxml.zookeeper.original.zkclient.OriginalClientAPIs.main(OriginalClientAPIs.java:112)
// Caused by: org.apache.zookeeper.KeeperException$NotEmptyException:
// KeeperErrorCode = Directory not empty for /user
// at org.apache.zookeeper.KeeperException.create(KeeperException.java:125)
// at org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
// at org.apache.zookeeper.ZooKeeper.delete(ZooKeeper.java:873)
// at org.I0Itec.zkclient.ZkConnection.delete(ZkConnection.java:102)
// at org.I0Itec.zkclient.ZkClient$9.call(ZkClient.java:940)
// at org.I0Itec.zkclient.ZkClient.retryUntilConnected(ZkClient.java:883)
// ... 3 more
SubscribeChildChanges.java
package com.yanxml.zookeeper.original.zkclient;import java.util.List;
import org.I0Itec.zkclient.IZkChildListener;
import org.I0Itec.zkclient.ZkClient;public class SubscribeChildChanges {private static class ZkChildListener implements IZkChildListener{public void handleChildChange(String parentPath, List<String> currentChilds)throws Exception {System.out.println(parentPath);System.out.println(currentChilds.toString());}}public static void main(String[] args) throws InterruptedException {OriginalClientAPIs apisDemo = new OriginalClientAPIs();// 获取client端ZkClient zkClient = apisDemo.getClient();// 注意 这个方法只能往下监听一层 子子节点的改变不能获取到zkClient.subscribeChildChanges("/user", new ZkChildListener());Thread.sleep(Integer.MAX_VALUE);}}SubscribeDataChanges.java
package com.yanxml.zookeeper.original.zkclient;import org.I0Itec.zkclient.IZkDataListener;
import org.I0Itec.zkclient.ZkClient;public class SubscribeDataChanges {private static class ZkDataListener implements IZkDataListener{public void handleDataChange(String dataPath, Object data)throws Exception {System.out.println(dataPath+":"+data.toString());}public void handleDataDeleted(String dataPath) throws Exception {System.out.println("Deleted:"+dataPath);}}public static void main(String[] args) throws InterruptedException {OriginalClientAPIs apisDemo = new OriginalClientAPIs();// 获取client端ZkClient zkClient = apisDemo.getClient();// 注意 这个方法只能往下监听一层 子子节点的改变不能获取到zkClient.subscribeDataChanges("/user", new ZkDataListener());Thread.sleep(Integer.MAX_VALUE);// 监听相关的方法
// zkClient.unsubscribeAll();
// zkClient.unsubscribeChildChanges(arg0, arg1);
// zkClient.unsubscribeDataChanges(arg0, arg1);
// zkClient.unsubscribeStateChanges(stateListener);}}- Curator
<!-- cursor --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-recipes</artifactId><version>2.8.0</version></dependency><!-- fast json --><!-- https://mvnrepository.com/artifact/com.alibaba/fastjson --><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.28</version></dependency>CuratorAPIs
package com.yanxml.zookeeper.original.curator;import java.security.NoSuchAlgorithmException;
import java.security.acl.Acl;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.api.BackgroundCallback;
import org.apache.curator.framework.api.CuratorEvent;
import org.apache.curator.framework.recipes.cache.NodeCache;
import org.apache.curator.framework.recipes.cache.NodeCacheListener;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.RetryUntilElapsed;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs.Perms;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;
import org.apache.zookeeper.data.Stat;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;import com.yanxml.zookeeper.config.ZooKeeperConfig;// curator 馆长public class CuratorAPIs {// Get The ZkClientpublic static CuratorFramework getClient() {CuratorFramework zkClient = null;// RetryPolicy 重试策略 Elapsed 运行// RetryUntilElapsed(maxElapsedTimeMs, sleepMsBetweenRetries)RetryPolicy retryPolicy = new RetryUntilElapsed(5000, 1000);// create method 1:// zkClient = CuratorFrameworkFactory.newClient(ZooKeeperConfig.ZOOURLS,// retryPolicy);// create method 2:zkClient = CuratorFrameworkFactory.builder().connectString(ZooKeeperConfig.ZOOURLS).connectionTimeoutMs(5000).sessionTimeoutMs(5000).retryPolicy(retryPolicy).build();zkClient.start();return zkClient;}// create the zk nodepublic boolean createZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {// 如何将一个对象转换为二进制流// EPHEMERAL短暂的String path = curatorFramework.create().creatingParentsIfNeeded().withMode(CreateMode.EPHEMERAL).forPath("/user/sean", "123".getBytes());System.out.println("Create Path: " + path);flag = true;}return flag;}// delete the zk nodepublic boolean deleteZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {curatorFramework.delete().deletingChildrenIfNeeded().withVersion(-1).forPath("/user/sean");flag = true;}return flag;}// get the zk nodepublic boolean getZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {Stat stat = new Stat();byte result[] = curatorFramework.getData().storingStatIn(stat).forPath("/user/sean");System.out.println(new String(result));flag = true;}return flag;}// get the child zk nodepublic boolean getChildZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {List<String> resultList = curatorFramework.getChildren().forPath("/user");System.out.println(resultList.toString());flag = true;}return flag;}// change the child zk nodepublic boolean changeZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {Stat stat = new Stat();curatorFramework.getData().storingStatIn(stat).forPath("/user/sean");curatorFramework.setData().withVersion(stat.getVersion()).forPath("/user/sean", "456".getBytes());flag = true;}return flag;}// check the child zk nodepublic boolean checkZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;ExecutorService es = Executors.newFixedThreadPool(5);if (null != curatorFramework) {// 获取节点的状态值Stat stat = curatorFramework.checkExists().forPath("/user/sean");System.out.println(stat.toString());curatorFramework.checkExists().inBackground(new BackgroundCallback() {public void processResult(CuratorFramework arg0,CuratorEvent arg1) throws Exception {Stat stat = arg1.getStat();System.out.println(stat);// arg1.getContext() 即为"123" 存储在ZkNode内的String 字符串System.out.println(arg1.getContext());}}, "123", es).forPath("/user/sean");flag = true;}return flag;}// Subscribe Node & child Nodepublic static boolean subscribeZkNode(CuratorFramework curatorFramework)throws Exception {boolean flag = false;if (null != curatorFramework) {flag = true;// NodeCache The cache value&stat of zkfinal NodeCache nodeCache = new NodeCache(curatorFramework,"/user/sean");nodeCache.start();nodeCache.getListenable().addListener(new NodeCacheListener() {public void nodeChanged() throws Exception {byte currentData[] = nodeCache.getCurrentData().getData();System.out.println("CurrentData:" + new String(currentData));}});}return flag;}// Subscribe Node & child Nodepublic static boolean subscribeChildZkNode(CuratorFramework curatorFramework) throws Exception {boolean flag = false;if (null != curatorFramework) {flag = true;// NodeCache The cache value&stat of zkfinal PathChildrenCache childNodeCache = new PathChildrenCache(curatorFramework, "/user/sean", true);childNodeCache.start();childNodeCache.getListenable().addListener(new PathChildrenCacheListener() {public void childEvent(CuratorFramework zkClient,PathChildrenCacheEvent event) throws Exception {// TODO Auto-generated method stubswitch (event.getType()) {case CHILD_ADDED : {System.out.println("Add Child Node");break;}case CHILD_UPDATED : {System.out.println("Update Child Node");break;}case CHILD_REMOVED : {System.out.println("Remove Child Node");break;}default : {System.out.println("Default");break;}}}});}return flag;}public static boolean authorZkNode(CuratorFramework curatorFramework) throws Exception{boolean flag = false;if (null != curatorFramework) {ACL acl = new ACL(Perms.READ,new Id("ip","192.168.100.204"));// digest 所有权限都有
// Acl aclDigest =Acl ACL aclDigest = new ACL(Perms.READ|Perms.WRITE,new Id("digest",DigestAuthenticationProvider.generateDigest("jike:123456")));ArrayList<ACL> acls = new ArrayList<ACL>();acls.add(acl);acls.add(aclDigest);// add the acls nodeString path = curatorFramework.create().creatingParentsIfNeeded().withMode(CreateMode.PERSISTENT).withACL(acls).forPath("/jike/3","123".getBytes());System.out.println(path);flag = true;}return flag;}public static void main(String[] args) throws Exception {CuratorAPIs curatorApIs = new CuratorAPIs();CuratorFramework curatorFramework = curatorApIs.getClient();// Create The Zk NodecuratorApIs.createZkNode(curatorFramework);// Delete The Zk Node// curatorApIs.deleteZkNode(curatorFramework);// Get The Zk NodecuratorApIs.getZkNode(curatorFramework);// Get The Child Zk NodecuratorApIs.getChildZkNode(curatorFramework);// Change The Zk Node// curatorApIs.changeZkNode(curatorFramework);// Check The Zk Node
// curatorApIs.checkZkNode(curatorFramework);curatorApIs.authorZkNode(curatorFramework);// 2^32-1Thread.sleep(Integer.MAX_VALUE);}}Reference
[1]. zookeeper 操作命令
[2]. zookeeper系列（一）zookeeper基础
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