Zookeeper客户端使用（使用Curator）
Zookeeper客户端（使用Curator）
三、使用curator客户端
在pom.xml中加入依赖
<dependency> <groupId>org.apache.curator</groupId> <artifactId>curator-framework</artifactId> <version>2.12.0</version> </dependency> <dependency> <groupId>org.apache.curator</groupId> <artifactId>curator-recipes</artifactId> <version>2.11.0</version> </dependency>
直接上代码：
1 /** 2 * Project Name:mk-project <br> 3 * Package Name:com.suns.zookeeper.curator <br> 4 * 5 * @author mk <br> 6 * Date:2018-10-31 14:03 <br> 7 */ 8 9 package com.suns.zookeeper.curator; 10 11 import org.apache.curator.RetryPolicy; 12 import org.apache.curator.framework.CuratorFramework; 13 import org.apache.curator.framework.CuratorFrameworkFactory; 14 import org.apache.curator.framework.recipes.cache.*; 15 import org.apache.curator.retry.ExponentialBackoffRetry; 16 import org.apache.zookeeper.CreateMode; 17 import org.apache.zookeeper.data.Stat; 18 19 import java.util.concurrent.TimeUnit; 20 21 /** 22 * curator客户端使用 23 * 24 * 和原生zookeeper优点： 25 * 1.使用api更方便,功能更丰富 26 * 2.监听节点数据改变或者子节点变化，只需要订阅一次，便可以一直使用。而原生zookeeper的监听是一次性的，需要重复注册。 27 * 3.链式编程 28 * 29 * Curator包含了几个包： 30 * curator-framework：对zookeeper的底层api的一些封装 31 * curator-client：提供一些客户端的操作，例如重试策略等 32 * curator-recipes：封装了一些高级特性，如：Cache事件监听、选举、分布式锁、分布式计数器、分布式Barrier等 33 * ClassName: ZkCuratorTest <br> 34 * Description: <br> 35 * @author mk 36 * @Date 2018-10-31 14:03 <br> 37 * @version 38 */ 39 public class ZkCuratorTest { 40 41 public static final String connect = "127.0.0.1:2181"; 42 private static CuratorFramework curatorFramework = null; 43 private static String nodePath = "/curator1"; 44 private static String nodeChildPath = "/curator1/n1/n11/n111/n1111"; 45 46 public static void main(String[] args) throws Exception { 47 48 //初始化 49 init(connect,5000); 50 51 //监听节点数据改变或者子节点变化，只需要订阅一次，便可以一直使用。而原生zookeeper的监听是一次性的，需要重复注册。 52 listener(nodePath); 53 54 //新增 55 create(nodePath,"n1"); 56 //递归新增 57 createRecursion(nodeChildPath,"n1"); 58 59 //查询 60 query(nodePath); 61 62 TimeUnit.SECONDS.sleep(2); 63 64 //修改 65 update(nodePath,"n11"); 66 67 //单个节点删除 68 // delete(nodePath); 69 //递归删除 70 deleteRecursion(nodePath); 71 72 } 73 74 private static void deleteRecursion(String path) throws Exception { 75 Void aVoid = curatorFramework.delete().deletingChildrenIfNeeded().forPath(path); 76 System.out.println("delete:"+"["+path+"],result:"+aVoid); 77 } 78 79 private static void delete(String path) throws Exception { 80 Void aVoid = curatorFramework.delete().forPath(path); 81 System.out.println("delete:"+"["+path+"],result:"+aVoid); 82 83 } 84 85 private static void update(String path, String data) throws Exception { 86 Stat stat = curatorFramework.setData().forPath(path, data.getBytes()); 87 System.out.println("setData:"+"["+path+"],stat:"+stat); 88 89 } 90 91 private static void query(String path) throws Exception { 92 byte[] bytes = curatorFramework.getData().forPath(path); 93 System.out.println("query:"+"["+path+"],result:"+new String(bytes)); 94 95 } 96 97 private static void createRecursion(String path,String data) throws Exception { 98 String result = curatorFramework.create().creatingParentContainersIfNeeded().withMode(CreateMode.PERSISTENT).forPath(path, data.getBytes()); 99 System.out.println("create:"+"["+path+"-->"+data+"],result:"+result); 100 101 } 102 103 private static void create(String path, String data) throws Exception { 104 // Stat stat = curatorFramework.checkExists().forPath(path); 105 // if(null != stat){ 106 // System.out.println("节点["+path+"]已存在，不能新增"); 107 // return; 108 // } 109 String result = curatorFramework.create().creatingParentsIfNeeded().withMode(CreateMode.PERSISTENT).forPath(path, data.getBytes()); 110 System.out.println("create:"+"["+path+"-->"+data+"],result:"+result); 111 } 112 113 private static void listener(String path) throws Exception { 114 115 //监听节点内容改变 116 final NodeCache nodeCache = new NodeCache(curatorFramework, path); 117 nodeCache.start(); 118 /*nodeCache.getListenable().addListener(new NodeCacheListener() { 119 @Override 120 public void nodeChanged() throws Exception { 121 System.out.println("节点内容发生变化----->"+nodeCache.getCurrentData()); 122 } 123 });*/ 124 125 //使用lambda表达式-jdk1.8以上 126 nodeCache.getListenable().addListener(()->{System.out.println("节点内容发生变化----->"+nodeCache.getCurrentData());}); 127 128 129 //监听子节点改变 130 final PathChildrenCache pathChildrenCache = new PathChildrenCache(curatorFramework, path, true); 131 pathChildrenCache.start(PathChildrenCache.StartMode.POST_INITIALIZED_EVENT); 132 /* pathChildrenCache.getListenable().addListener(new PathChildrenCacheListener() { 133 @Override 134 public void childEvent(CuratorFramework curatorFramework, PathChildrenCacheEvent pathChildrenCacheEvent) throws Exception { 135 switch (pathChildrenCacheEvent.getType() ){ 136 case CHILD_ADDED: 137 System.out.println("新增子节点"+pathChildrenCache.getCurrentData()); 138 break; 139 case CHILD_UPDATED: 140 System.out.println("更新子节点"+pathChildrenCache.getCurrentData()); 141 break; 142 case CHILD_REMOVED: 143 System.out.println("删除子节点"+pathChildrenCache.getCurrentData()); 144 break; 145 default:break; 146 } 147 } 148 });*/ 149 //使用lambda表达式-jdk1.8以上 150 pathChildrenCache.getListenable().addListener((curatorFramework,pathChildrenCacheEvent)-> 151 {switch (pathChildrenCacheEvent.getType() ){ 152 case CHILD_ADDED: 153 System.out.println("新增子节点"+pathChildrenCache.getCurrentData()); 154 break; 155 case CHILD_UPDATED: 156 System.out.println("更新子节点"+pathChildrenCache.getCurrentData()); 157 break; 158 case CHILD_REMOVED: 159 System.out.println("删除子节点"+pathChildrenCache.getCurrentData()); 160 break; 161 default:break; 162 }}); 163 164 165 } 166 167 private static void init(String connect, int sessionTimeout) { 168 RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);//重试策略，初始等待1s,重试3次 169 //通过工厂获得CuratorFramework 170 curatorFramework = CuratorFrameworkFactory.builder() 171 .connectString(connect).connectionTimeoutMs(sessionTimeout).retryPolicy(retryPolicy).build(); 172 curatorFramework.start();//开启连接 173 System.out.println("curatorFramework start :" +connect); 174 } 175 176 }
运行截图：
