package cn.itcast.bigdata.zk;import java.io.IOException;
import java.util.List;import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;
import org.junit.Before;
import org.junit.Test;public class SimpleZkClient {private static final String connectString = "mini1:2181,mini2:2181,mini3:2181";private static final int sessionTimeout = 2000;ZooKeeper zkClient = null;@Beforepublic void init() throws Exception {zkClient = new ZooKeeper(connectString, sessionTimeout, new Watcher() {@Overridepublic void process(WatchedEvent event) {// 收到事件通知后的回调函数（应该是我们自己的事件处理逻辑）System.out.println(event.getType() + "---" + event.getPath());try {zkClient.getChildren("/", true);} catch (Exception e) {}}});}/*** 数据的增删改查* * @throws InterruptedException* @throws KeeperException*/// 创建数据节点到zk中public void testCreate() throws KeeperException, InterruptedException {// 参数1：要创建的节点的路径 参数2：节点大数据 参数3：节点的权限 参数4：节点的类型String nodeCreated = zkClient.create("/eclipse", "hellozk".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);//上传的数据可以是任何类型，但都要转成byte[]}//判断znode是否存在@Test	public void testExist() throws Exception{Stat stat = zkClient.exists("/eclipse", false);System.out.println(stat==null?"not exist":"exist");}// 获取子节点@Testpublic void getChildren() throws Exception {List<String> children = zkClient.getChildren("/", true);for (String child : children) {System.out.println(child);}Thread.sleep(Long.MAX_VALUE);}//获取znode的数据@Testpublic void getData() throws Exception {byte[] data = zkClient.getData("/eclipse", false, null);System.out.println(new String(data));}//删除znode@Testpublic void deleteZnode() throws Exception {//参数2：指定要删除的版本，-1表示删除所有版本zkClient.delete("/eclipse", -1);}//删除znode@Testpublic void setData() throws Exception {zkClient.setData("/app1", "imissyou angelababy".getBytes(), -1);byte[] data = zkClient.getData("/app1", false, null);System.out.println(new String(data));}}