curator客户端的使用

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                    curator客户端的使用

常用的zk java客户端
zk原生api
zkclient(两个老外的开源，更新比较慢，不建议使用)
curator

原生api的不足
超时重连，不支持自动，需要手动操作
Watch注册一次后会失效
不支持递归创建节点

Apache curator的优点
Apache的开源项目
解决watcher的注册一次就失效
Api更加简单易用
提供更多解决方案并且实现简单：比如 分布式锁
提供常用的ZooKeeper工具类
编程风格更爽
 

搭建maven工程，建立curator与zkserver的连接

添加maven依赖

<dependency>
			<groupId>org.apache.curator</groupId>
			<artifactId>curator-framework</artifactId>
			<version>4.0.0</version>
		</dependency>
		<dependency>
			<groupId>org.apache.curator</groupId>
			<artifactId>curator-recipes</artifactId>
			<version>4.0.0</version>
		</dependency>
		<dependency>
			<groupId>org.apache.zookeeper</groupId>
			<artifactId>zookeeper</artifactId>
			<version>3.4.11</version>
		</dependency>

会话连接与关闭

package com.example.curator;

import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.cache.ChildData;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCache.StartMode;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.RetryNTimes;

import java.util.List;

public class CuratorOperator {

	public CuratorFramework client = null;
	public static final String zkServerPath = "47.106.226.*:2181";

	/**
	 * 实例化zk客户端
	 */
	public CuratorOperator() {
		/**
		 * 同步创建zk示例，原生api是异步的
		 * 
		 * curator链接zookeeper的策略:ExponentialBackoffRetry
		 * baseSleepTimeMs：初始sleep的时间
		 * maxRetries：最大重试次数
		 * maxSleepMs：最大重试时间
		 */
//		RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 5);
		
		/**
		 * curator链接zookeeper的策略:RetryNTimes
		 * n：重试的次数
		 * sleepMsBetweenRetries：每次重试间隔的时间
		 */
		RetryPolicy retryPolicy = new RetryNTimes(3, 5000);
		
		/**
		 * curator链接zookeeper的策略:RetryOneTime
		 * sleepMsBetweenRetry:每次重试间隔的时间
		 */
//		RetryPolicy retryPolicy2 = new RetryOneTime(3000);
		
		/**
		 * 永远重试，不推荐使用
		 */
//		RetryPolicy retryPolicy3 = new RetryForever(retryIntervalMs)
		
		/**
		 * curator链接zookeeper的策略:RetryUntilElapsed
		 * maxElapsedTimeMs:最大重试时间
		 * sleepMsBetweenRetries:每次重试间隔
		 * 重试时间超过maxElapsedTimeMs后，就不再重试
		 */
//		RetryPolicy retryPolicy4 = new RetryUntilElapsed(2000, 3000);
		
		client = CuratorFrameworkFactory.builder()
				.connectString(zkServerPath)
				.sessionTimeoutMs(10000).retryPolicy(retryPolicy)
				.namespace("workspace").build();
		client.start();
	}
	
	/**
	 * 
	 * @Description: 关闭zk客户端连接
	 */
	public void closeZKClient() {
		if (client != null) {
			this.client.close();
		}
	}
	
	public static void main(String[] args) throws Exception {
		// 实例化
		CuratorOperator cto = new CuratorOperator();
		boolean isZkCuratorStarted = cto.client.isStarted();
		System.out.println("当前客户的状态：" + (isZkCuratorStarted ? "连接中" : "已关闭"));
		

		
		cto.closeZKClient();
		boolean isZkCuratorStarted2 = cto.client.isStarted();
		System.out.println("当前客户的状态：" + (isZkCuratorStarted2 ? "连接中" : "已关闭"));
	}
	
	public final static String ADD_PATH = "/super/imooc/d";
	
}

节点的增删改查
zk命名空间(workspace)


创建节点

		// 创建节点
		String nodePath = "/super/imooc";
		byte[] data = "superme".getBytes();
		cto.client.create().creatingParentsIfNeeded()
			.withMode(CreateMode.PERSISTENT)
			.withACL(Ids.OPEN_ACL_UNSAFE)
			.forPath(nodePath, data);

结果：

	// 更新节点数据
		byte[] newData = "batman".getBytes();
		cto.client.setData().withVersion(0).forPath(nodePath, newData);

// 删除节点
		cto.client.delete()
				  .guaranteed()					// 如果删除失败，那么在后端还是继续会删除，直到成功
				  .deletingChildrenIfNeeded()	// 如果有子节点，就删除
				  .withVersion(0)
				  .forPath(nodePath);

	// 读取节点数据
		Stat stat = new Stat();
		byte[] data = cto.client.getData().storingStatIn(stat).forPath(nodePath);
		System.out.println("节点" + nodePath + "的数据为: " + new String(data));
		System.out.println("该节点的版本号为: " + stat.getVersion());

	// 查询子节点
		List<String> childNodes = cto.client.getChildren()
											.forPath(nodePath);
		System.out.println("开始打印子节点：");
		for (String s : childNodes) {
			System.out.println(s);
		}

	// 判断节点是否存在,如果不存在则为空
		Stat statExist = cto.client.checkExists().forPath(nodePath + "/abc");
		System.out.println(statExist);
		

watch与acl的相关操作

MyWatcher.java(原生)

package com.imooc.curator;

import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;

public class MyWatcher implements Watcher {

	@Override
	public void process(WatchedEvent event) {
		System.out.println("触发watcher，节点路径为：" + event.getPath());
	}


}

 MyCuratorWatcher.java

package com.imooc.curator;

import org.apache.curator.framework.api.CuratorWatcher;
import org.apache.zookeeper.WatchedEvent;

public class MyCuratorWatcher implements CuratorWatcher {

	@Override
	public void process(WatchedEvent event) throws Exception {
		System.out.println("触发watcher，节点路径为：" + event.getPath());
	}

}

// watcher 事件  当使用usingWatcher的时候，监听只会触发一次，监听完毕后就销毁
		cto.client.getData().usingWatcher(new MyCuratorWatcher()).forPath(nodePath);
		cto.client.getData().usingWatcher(new MyWatcher()).forPath(nodePath);

nodeCache一次注册N次监听
为了让例子显示效果，可以在代码后加 Thread.sleep(10000000);方便客户端有时间操作显示效果

	// 为节点添加watcher
		// NodeCache: 监听数据节点的变更，会触发事件
		final NodeCache nodeCache = new NodeCache(cto.client, nodePath);
		// buildInitial : 初始化的时候获取node的值并且缓存
		nodeCache.start(true);
		if (nodeCache.getCurrentData() != null) {
			System.out.println("节点初始化数据为：" + new String(nodeCache.getCurrentData().getData()));
		} else {
			System.out.println("节点初始化数据为空...");
		}
		nodeCache.getListenable().addListener(new NodeCacheListener() {
			public void nodeChanged() throws Exception {
				if (nodeCache.getCurrentData() == null) {
					System.out.println("空");
					return;
				}
				String data = new String(nodeCache.getCurrentData().getData());
				System.out.println("节点路径：" + nodeCache.getCurrentData().getPath() + "数据：" + data);
			}
		});
		

PathChildrenCache子节点监听

	// 为子节点添加watcher
		// PathChildrenCache: 监听数据节点的增删改，会触发事件
		String childNodePathCache =  nodePath;
		// cacheData: 设置缓存节点的数据状态
		final PathChildrenCache childrenCache = new PathChildrenCache(cto.client, childNodePathCache, true);
		/**
		 * StartMode: 初始化方式
		 * POST_INITIALIZED_EVENT：异步初始化，初始化之后会触发事件
		 * NORMAL：异步初始化
		 * BUILD_INITIAL_CACHE：同步初始化
		 */
		childrenCache.start(StartMode.POST_INITIALIZED_EVENT);

		List<ChildData> childDataList = childrenCache.getCurrentData();
		System.out.println("当前数据节点的子节点数据列表：");
		for (ChildData cd : childDataList) {
			String childData = new String(cd.getData());
			System.out.println(childData);
		}

		childrenCache.getListenable().addListener(new PathChildrenCacheListener() {
			public void childEvent(CuratorFramework client, PathChildrenCacheEvent event) throws Exception {
				if(event.getType().equals(PathChildrenCacheEvent.Type.INITIALIZED)){
					System.out.println("子节点初始化ok...");
				}

				else if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_ADDED)){
					String path = event.getData().getPath();
					if (path.equals(ADD_PATH)) {
						System.out.println("添加子节点:" + event.getData().getPath());
						System.out.println("子节点数据:" + new String(event.getData().getData()));
					} else if (path.equals("/super/imooc/e")) {
						System.out.println("添加不正确...");
					}

				}else if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_REMOVED)){
					System.out.println("删除子节点:" + event.getData().getPath());
				}else if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)){
					System.out.println("修改子节点路径:" + event.getData().getPath());
					System.out.println("修改子节点数据:" + new String(event.getData().getData()));
				}
			}
		});

Watcher 统一配置



添加Maven依赖

<!-- 时间操作组件 -->
		<dependency>
			<groupId>joda-time</groupId>
			<artifactId>joda-time</artifactId>
			<version>2.5</version>
		</dependency>
		<!-- Apache工具组件 -->
		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-lang3</artifactId>
			<version>3.3.2</version>
		</dependency>
		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-io</artifactId>
			<version>1.3.2</version>
		</dependency>
		<dependency>
			<groupId>commons-net</groupId>
			<artifactId>commons-net</artifactId>
			<version>3.3</version>
		</dependency>
		<!-- Jackson Json处理工具包 -->
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-databind</artifactId>
			<version>2.7.4</version>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-core</artifactId>
			<version>2.7.4</version>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-annotations</artifactId>
			<version>2.7.4</version>
		</dependency>

项目目录


Client1.java，Client2.java，Client3.java 内容一致
Client1.java

package com.example.curator.checkConfig;

import com.example.curator.utils.JsonUtils;
import com.example.curator.utils.RedisConfig;
import org.apache.commons.lang3.StringUtils;
import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCache.StartMode;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.RetryNTimes;

import java.util.concurrent.CountDownLatch;

public class Client1 {

	public CuratorFramework client = null;
	public static final String zkServerPath = "47.106.226.*:2181";

	public Client1() {
		RetryPolicy retryPolicy = new RetryNTimes(3, 5000);
		client = CuratorFrameworkFactory.builder()
				.connectString(zkServerPath)
				.sessionTimeoutMs(10000).retryPolicy(retryPolicy)
				.namespace("workspace").build();
		client.start();
	}
	
	public void closeZKClient() {
		if (client != null) {
			this.client.close();
		}
	}
	
//	public final static String CONFIG_NODE = "/super/imooc/redis-config";
	public final static String CONFIG_NODE_PATH = "/super/imooc";
	public final static String SUB_PATH = "/redis-config";
	public static CountDownLatch countDown = new CountDownLatch(1);
	
	public static void main(String[] args) throws Exception {
		Client1 cto = new Client1();
		System.out.println("client1 启动成功...");
		
		final PathChildrenCache childrenCache = new PathChildrenCache(cto.client, CONFIG_NODE_PATH, true);
		childrenCache.start(StartMode.BUILD_INITIAL_CACHE);
		
		// 添加监听事件
		childrenCache.getListenable().addListener(new PathChildrenCacheListener() {
			public void childEvent(CuratorFramework client, PathChildrenCacheEvent event) throws Exception {
				// 监听节点变化
				if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)){
					String configNodePath = event.getData().getPath();
					if (configNodePath.equals(CONFIG_NODE_PATH + SUB_PATH)) {
						System.out.println("监听到配置发生变化，节点路径为:" + configNodePath);
						
						// 读取节点数据
						String jsonConfig = new String(event.getData().getData());
						System.out.println("节点" + CONFIG_NODE_PATH + "的数据为: " + jsonConfig);
						
						// 从json转换配置
						RedisConfig redisConfig = null;
						if (StringUtils.isNotBlank(jsonConfig)) {
							redisConfig = JsonUtils.jsonToPojo(jsonConfig, RedisConfig.class);
						}
						
						// 配置不为空则进行相应操作
						if (redisConfig != null) {
							String type = redisConfig.getType();
							String url = redisConfig.getUrl();
							String remark = redisConfig.getRemark();
							// 判断事件
							if (type.equals("add")) {
								System.out.println("监听到新增的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载新的配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功，已经添加到项目中");
								// ... 拷贝文件到项目目录
							} else if (type.equals("update")) {
								System.out.println("监听到更新的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功...");
								System.out.println("删除项目中原配置文件...");
								Thread.sleep(100);
								// ... 删除原文件
								System.out.println("拷贝配置文件到项目目录...");
								// ... 拷贝文件到项目目录
							} else if (type.equals("delete")) {
								System.out.println("监听到需要删除配置");
								System.out.println("删除项目中原配置文件...");
							}
							
							// TODO 视情况统一重启服务
						}
					}
				}
			}
		});
		
		countDown.await();
		
		cto.closeZKClient();
	}
	
}

Client2.java

package com.example.curator.checkConfig;

import com.example.curator.utils.JsonUtils;
import com.example.curator.utils.RedisConfig;
import org.apache.commons.lang3.StringUtils;
import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCache.StartMode;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.RetryNTimes;

import java.util.concurrent.CountDownLatch;

public class Client2 {

	public CuratorFramework client = null;
	public static final String zkServerPath = "47.106.226.*:2181";

	public Client1() {
		RetryPolicy retryPolicy = new RetryNTimes(3, 5000);
		client = CuratorFrameworkFactory.builder()
				.connectString(zkServerPath)
				.sessionTimeoutMs(10000).retryPolicy(retryPolicy)
				.namespace("workspace").build();
		client.start();
	}
	
	public void closeZKClient() {
		if (client != null) {
			this.client.close();
		}
	}
	
//	public final static String CONFIG_NODE = "/super/imooc/redis-config";
	public final static String CONFIG_NODE_PATH = "/super/imooc";
	public final static String SUB_PATH = "/redis-config";
	public static CountDownLatch countDown = new CountDownLatch(1);
	
	public static void main(String[] args) throws Exception {
		Client1 cto = new Client1();
		System.out.println("client1 启动成功...");
		
		final PathChildrenCache childrenCache = new PathChildrenCache(cto.client, CONFIG_NODE_PATH, true);
		childrenCache.start(StartMode.BUILD_INITIAL_CACHE);
		
		// 添加监听事件
		childrenCache.getListenable().addListener(new PathChildrenCacheListener() {
			public void childEvent(CuratorFramework client, PathChildrenCacheEvent event) throws Exception {
				// 监听节点变化
				if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)){
					String configNodePath = event.getData().getPath();
					if (configNodePath.equals(CONFIG_NODE_PATH + SUB_PATH)) {
						System.out.println("监听到配置发生变化，节点路径为:" + configNodePath);
						
						// 读取节点数据
						String jsonConfig = new String(event.getData().getData());
						System.out.println("节点" + CONFIG_NODE_PATH + "的数据为: " + jsonConfig);
						
						// 从json转换配置
						RedisConfig redisConfig = null;
						if (StringUtils.isNotBlank(jsonConfig)) {
							redisConfig = JsonUtils.jsonToPojo(jsonConfig, RedisConfig.class);
						}
						
						// 配置不为空则进行相应操作
						if (redisConfig != null) {
							String type = redisConfig.getType();
							String url = redisConfig.getUrl();
							String remark = redisConfig.getRemark();
							// 判断事件
							if (type.equals("add")) {
								System.out.println("监听到新增的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载新的配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功，已经添加到项目中");
								// ... 拷贝文件到项目目录
							} else if (type.equals("update")) {
								System.out.println("监听到更新的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功...");
								System.out.println("删除项目中原配置文件...");
								Thread.sleep(100);
								// ... 删除原文件
								System.out.println("拷贝配置文件到项目目录...");
								// ... 拷贝文件到项目目录
							} else if (type.equals("delete")) {
								System.out.println("监听到需要删除配置");
								System.out.println("删除项目中原配置文件...");
							}
							
							// TODO 视情况统一重启服务
						}
					}
				}
			}
		});
		
		countDown.await();
		
		cto.closeZKClient();
	}
	
}

Client3.java

package com.example.curator.checkConfig;

import com.example.curator.utils.JsonUtils;
import com.example.curator.utils.RedisConfig;
import org.apache.commons.lang3.StringUtils;
import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCache.StartMode;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.RetryNTimes;

import java.util.concurrent.CountDownLatch;

public class Client3 {

	public CuratorFramework client = null;
	public static final String zkServerPath = "47.106.226.*:2181";

	public Client1() {
		RetryPolicy retryPolicy = new RetryNTimes(3, 5000);
		client = CuratorFrameworkFactory.builder()
				.connectString(zkServerPath)
				.sessionTimeoutMs(10000).retryPolicy(retryPolicy)
				.namespace("workspace").build();
		client.start();
	}
	
	public void closeZKClient() {
		if (client != null) {
			this.client.close();
		}
	}
	
//	public final static String CONFIG_NODE = "/super/imooc/redis-config";
	public final static String CONFIG_NODE_PATH = "/super/imooc";
	public final static String SUB_PATH = "/redis-config";
	public static CountDownLatch countDown = new CountDownLatch(1);
	
	public static void main(String[] args) throws Exception {
		Client1 cto = new Client1();
		System.out.println("client1 启动成功...");
		
		final PathChildrenCache childrenCache = new PathChildrenCache(cto.client, CONFIG_NODE_PATH, true);
		childrenCache.start(StartMode.BUILD_INITIAL_CACHE);
		
		// 添加监听事件
		childrenCache.getListenable().addListener(new PathChildrenCacheListener() {
			public void childEvent(CuratorFramework client, PathChildrenCacheEvent event) throws Exception {
				// 监听节点变化
				if(event.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)){
					String configNodePath = event.getData().getPath();
					if (configNodePath.equals(CONFIG_NODE_PATH + SUB_PATH)) {
						System.out.println("监听到配置发生变化，节点路径为:" + configNodePath);
						
						// 读取节点数据
						String jsonConfig = new String(event.getData().getData());
						System.out.println("节点" + CONFIG_NODE_PATH + "的数据为: " + jsonConfig);
						
						// 从json转换配置
						RedisConfig redisConfig = null;
						if (StringUtils.isNotBlank(jsonConfig)) {
							redisConfig = JsonUtils.jsonToPojo(jsonConfig, RedisConfig.class);
						}
						
						// 配置不为空则进行相应操作
						if (redisConfig != null) {
							String type = redisConfig.getType();
							String url = redisConfig.getUrl();
							String remark = redisConfig.getRemark();
							// 判断事件
							if (type.equals("add")) {
								System.out.println("监听到新增的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载新的配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功，已经添加到项目中");
								// ... 拷贝文件到项目目录
							} else if (type.equals("update")) {
								System.out.println("监听到更新的配置，准备下载...");
								// ... 连接ftp服务器，根据url找到相应的配置
								Thread.sleep(500);
								System.out.println("开始下载配置文件，下载路径为<" + url + ">");
								// ... 下载配置到你指定的目录
								Thread.sleep(1000);
								System.out.println("下载成功...");
								System.out.println("删除项目中原配置文件...");
								Thread.sleep(100);
								// ... 删除原文件
								System.out.println("拷贝配置文件到项目目录...");
								// ... 拷贝文件到项目目录
							} else if (type.equals("delete")) {
								System.out.println("监听到需要删除配置");
								System.out.println("删除项目中原配置文件...");
							}
							
							// TODO 视情况统一重启服务
						}
					}
				}
			}
		});
		
		countDown.await();
		
		cto.closeZKClient();
	}
	
}

 JsonUtils.java

package com.example.curator.utils;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.List;

/**
 * 
 * @Title: JsonUtils.java
 * @Package com.lee.utils
 * @Description: JSON/对象转换类
 * Copyright: Copyright (c) 2016
 * Company:Nathan.Lee.Salvatore
 * 
 * @author leechenxiang
 * @date 2016年4月29日 下午11:05:03
 * @version V1.0
 */
public class JsonUtils {

    // 定义jackson对象
    private static final ObjectMapper MAPPER = new ObjectMapper();

    /**
     * 将对象转换成json字符串。
     * <p>Title: pojoToJson</p>
     * <p>Description: </p>
     * @param data
     * @return
     */
    public static String objectToJson(Object data) {
    	try {
			String string = MAPPER.writeValueAsString(data);
			return string;
		} catch (JsonProcessingException e) {
			e.printStackTrace();
		}
    	return null;
    }
    
    /**
     * 将json结果集转化为对象
     * 
     * @param jsonData json数据
     * @param clazz 对象中的object类型
     * @return
     */
    public static <T> T jsonToPojo(String jsonData, Class<T> beanType) {
        try {
            T t = MAPPER.readValue(jsonData, beanType);
            return t;
        } catch (Exception e) {
        	e.printStackTrace();
        }
        return null;
    }
    
    /**
     * 将json数据转换成pojo对象list
     * <p>Title: jsonToList</p>
     * <p>Description: </p>
     * @param jsonData
     * @param beanType
     * @return
     */
    public static <T>List<T> jsonToList(String jsonData, Class<T> beanType) {
    	JavaType javaType = MAPPER.getTypeFactory().constructParametricType(List.class, beanType);
    	try {
    		List<T> list = MAPPER.readValue(jsonData, javaType);
    		return list;
		} catch (Exception e) {
			e.printStackTrace();
		}
    	
    	return null;
    }
    
}

RedisConfig.java

package com.example.curator.utils;

public class RedisConfig {

	private String type;	// add 新增配置	update 更新配置	delete 删除配置
	private String url;		// 如果是add或update，则提供下载地址
	private String remark;	// 备注
	
	public String getType() {
		return type;
	}
	public void setType(String type) {
		this.type = type;
	}
	public String getUrl() {
		return url;
	}
	public void setUrl(String url) {
		this.url = url;
	}
	public String getRemark() {
		return remark;
	}
	public void setRemark(String remark) {
		this.remark = remark;
	}
}

RedisConfig.json

{"type":"add","url":"ftp://192.168.10.123/config/redis.xml","remark":"add"}
{"type":"update","url":"ftp://192.168.10.123/config/redis.xml","remark":"update"}
{"type":"delete","url":"","remark":"delete"}

分别运行Client1.java，Client2.java，Client3.java
 

[zk: localhost:2181(CONNECTED) 7] create /workspace/super/imooc/redis-config {"type":"add","url":"ftp://192.168.10.123/config/redis.xml","remark":"add"}
Created /workspace/super/imooc/redis-config
[zk: localhost:2181(CONNECTED) 8] set /workspace/super/imooc/redis-config {"type":"add","url":"ftp://192.168.10.123/config/redis.xml","remark":"add"}   
cZxid = 0x300000031
ctime = Wed Dec 05 16:34:22 CST 2018
mZxid = 0x300000032
mtime = Wed Dec 05 16:34:49 CST 2018
pZxid = 0x300000031
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 75
numChildren = 0

结果：





acl的相关操作

CuratorAcl.java

package com.imooc.curator;

import java.util.ArrayList;
import java.util.List;

import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.RetryNTimes;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooDefs.Perms;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;

import com.imooc.utils.AclUtils;

public class CuratorAcl {

	public CuratorFramework client = null;
	public static final String zkServerPath = "47.106.226.16:2181";

	public CuratorAcl() {
		RetryPolicy retryPolicy = new RetryNTimes(3, 5000);
		client = CuratorFrameworkFactory.builder().authorization("digest", "imooc1:123456".getBytes())
				.connectString(zkServerPath)
				.sessionTimeoutMs(10000).retryPolicy(retryPolicy)
				.namespace("workspace").build();
		client.start();
	}
	
	public void closeZKClient() {
		if (client != null) {
			this.client.close();
		}
	}
	
	public static void main(String[] args) throws Exception {
		// 实例化
		CuratorAcl cto = new CuratorAcl();
		boolean isZkCuratorStarted = cto.client.isStarted();
		System.out.println("当前客户的状态：" + (isZkCuratorStarted ? "连接中" : "已关闭"));
		
		String nodePath = "/acl/father/child/sub";
		
		List<ACL> acls = new ArrayList<ACL>();
		Id imooc1 = new Id("digest", AclUtils.getDigestUserPwd("imooc1:123456"));
		Id imooc2 = new Id("digest", AclUtils.getDigestUserPwd("imooc2:123456"));
		acls.add(new ACL(Perms.ALL, imooc1));
		acls.add(new ACL(Perms.READ, imooc2));
		acls.add(new ACL(Perms.DELETE | Perms.CREATE, imooc2));
		
		// 创建节点
//		byte[] data = "spiderman".getBytes();
//		cto.client.create().creatingParentsIfNeeded()
//				.withMode(CreateMode.PERSISTENT)
//				.withACL(acls, true)
//				.forPath(nodePath, data);
		

		cto.client.setACL().withACL(acls).forPath("/curatorNode");
		
		// 更新节点数据
//		byte[] newData = "batman".getBytes();
//		cto.client.setData().withVersion(0).forPath(nodePath, newData);
		
		// 删除节点
//		cto.client.delete().guaranteed().deletingChildrenIfNeeded().withVersion(0).forPath(nodePath);
		
		// 读取节点数据
//		Stat stat = new Stat();
//		byte[] data = cto.client.getData().storingStatIn(stat).forPath(nodePath);
//		System.out.println("节点" + nodePath + "的数据为: " + new String(data));
//		System.out.println("该节点的版本号为: " + stat.getVersion());
		
		
		cto.closeZKClient();
		boolean isZkCuratorStarted2 = cto.client.isStarted();
		System.out.println("当前客户的状态：" + (isZkCuratorStarted2 ? "连接中" : "已关闭"));
	}
	
}

AclUtils.java 

package com.imooc.utils;

import java.io.IOException;
import java.security.NoSuchAlgorithmException;

import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;

public class AclUtils {
	
	public static String getDigestUserPwd(String id) {
		String digest = "";
		try {
			digest = DigestAuthenticationProvider.generateDigest(id);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		return digest;
	}
	
	public static void main(String[] args) throws IOException, InterruptedException, KeeperException, Exception {
		String id = "imooc:imooc";
		String idDigested = getDigestUserPwd(id);
		System.out.println(idDigested);
	}
}