ZooKeeper之java客户端访问-入门介绍

上篇简单的介绍了单点部署ZooKeeper及节点管理。

这里介绍下如何通过java客户端进行各个节点的管理。

具体就不一一介绍，相信从代码的注释中就可以看明白

首先创建一个zookeeper的基础类，里面包含了基本的节点管理方法，如下：

package com.zktest.newtest;import java.io.IOException;import java.util.List;import java.util.concurrent.CountDownLatch;import org.apache.zookeeper.CreateMode;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.Watcher.Event.KeeperState;import org.apache.zookeeper.ZooDefs.Ids;import org.apache.zookeeper.ZooKeeper;import org.apache.zookeeper.data.Stat;public class BaseZookeeper implements Watcher{public ZooKeeper zooKeeper;private static final int SESSION_TIME_OUT = 2000;private CountDownLatch countDownLatch = new CountDownLatch(1);/** * 连接zookeeper *  * @param host * @throws IOException * @throws InterruptedException */public void connectZookeeper(String host) throws IOException,InterruptedException{zooKeeper = new ZooKeeper(host, SESSION_TIME_OUT, this);countDownLatch.await();System.out.println("zookeeper connect ok");}/** * 实现watcher的接口方法，当连接zookeeper成功后，zookeeper会通过此方法通知watcher<br> * 此处为如果接受到连接成功的event，则countDown，让当前线程继续其他事情。 */@Overridepublic void process(WatchedEvent event){if (event.getState() == KeeperState.SyncConnected){System.out.println("watcher received event");countDownLatch.countDown();}}/** * 根据路径创建节点，并且设置节点数据 * @param path * @param data * @return * @throws KeeperException * @throws InterruptedException */public String createNode(String path, byte[] data) throws KeeperException,InterruptedException{return this.zooKeeper.create(path, data, Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT);}/** * 根据路径获取所有孩子节点 *  * @param path * @return * @throws KeeperException * @throws InterruptedException */public List<String> getChildren(String path) throws KeeperException,InterruptedException{return this.zooKeeper.getChildren(path, false);}public Stat setData(String path, byte [] data, int version) throws KeeperException, InterruptedException{return this.zooKeeper.setData(path, data, version);}/** * 根据路径获取节点数据 *  * @param path * @return * @throws KeeperException * @throws InterruptedException */public byte[] getData(String path) throws KeeperException,InterruptedException{return this.zooKeeper.getData(path, false, null);}/** * 删除节点 *  * @param path * @param version * @throws InterruptedException * @throws KeeperException */public void deletNode(String path, int version)throws InterruptedException, KeeperException{this.zooKeeper.delete(path, version);}/** * 关闭zookeeper连接 *  * @throws InterruptedException */public void closeConnect() throws InterruptedException{if (null != zooKeeper){zooKeeper.close();}}}

创建客户端进行测试，代码如下：

package com.spg.zktest.newtest;import java.io.IOException;import java.util.Arrays;import java.util.List;import org.apache.zookeeper.KeeperException;public class Client{/** * @param args * @throws InterruptedException  * @throws IOException  * @throws KeeperException  */public static void main(String[] args) throws IOException, InterruptedException, KeeperException{BaseZookeeper baseZookeeper = new BaseZookeeper();String host = "192.168.183.128:2181";// 连接zookeeperbaseZookeeper.connectZookeeper(host);System.out.println("--------connect zookeeper ok-----------");// 创建节点byte [] data = {1, 2, 3, 4, 5};String result = baseZookeeper.createNode("/test", data);System.out.println(result);System.out.println("--------create node ok-----------");// 获取某路径下所有节点List<String> children = baseZookeeper.getChildren("/");for (String child : children){System.out.println(child);}System.out.println("--------get children ok-----------");// 获取节点数据byte [] nodeData = baseZookeeper.getData("/test");System.out.println(Arrays.toString(nodeData));System.out.println("--------get node data ok-----------");// 更新节点数据data = "test data".getBytes();baseZookeeper.setData("/test", data, 0);System.out.println("--------set node data ok-----------");nodeData = baseZookeeper.getData("/test");System.out.println(Arrays.toString(nodeData));System.out.println("--------get node new data ok-----------");baseZookeeper.closeConnect();System.out.println("--------close zookeeper ok-----------");}}

从命令行中看操作后的结果，如下：

1：根目录下节点

2：查看test节点信息

OK，测试结果到此结束。