zookeeper基本操作

package os.zk.demo;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.util.List;import org.apache.hadoop.ha.protocolPB.ZKFCProtocolClientSideTranslatorPB;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 ZooKeeper zkCli = null;    @Before    public void init() throws IOException {        zkCli = new ZooKeeper("os-1:2181,os-2:2181,os-3:2181", 2000, new Watcher() {            @Override            public void process(WatchedEvent event) {                // TODO Auto-generated method stub                System.out.println("节点:"+event.getPath()+"发生了事件"+event.getType());            }        });    }    /*     * 在zookeeper中创建znode节点(临时/永久)     */    @Test    public void create() throws UnsupportedEncodingException, KeeperException, InterruptedException {        //PERSISTENT永久节点        String node1 = zkCli.create("/book", "读书".getBytes("utf-8"),Ids.OPEN_ACL_UNSAFE ,CreateMode.PERSISTENT);        //临时节点EPHEMERAL        String node2 = zkCli.create("/library", "图书馆".getBytes("utf-8"),Ids.OPEN_ACL_UNSAFE ,CreateMode.EPHEMERAL);        System.out.println("创建了一个永久节点:"+node1);        System.out.println("创建了一个临时节点:"+node2);    }    /*     * 活动znode节点数据     */    public void getData() throws KeeperException, InterruptedException, UnsupportedEncodingException {        byte[] data = zkCli.getData("/book", true,null );        System.out.println(new String(data,"utf-8"));    }    /*     * 修改节点数据     */    @Test    public void testModifyNodeData() throws UnsupportedEncodingException, KeeperException, InterruptedException {        // 修改数据时的版本号用 -1表示所有版本        Stat setData = zkCli.setData("/book", "美女".getBytes("utf-8"), -1);        byte [] data = zkCli.getData("/book", true, null);        System.out.println("修改之后的值为:"+new String(data,"utf-8"));    }    /*     * 删除数据节点     */    @Test    public void testDelZnode() throws InterruptedException, KeeperException {         Stat exists = zkCli.exists("/book", true);        if(exists!=null) {            zkCli.delete("/book", -1);        }    }    public static void main(String[] args) throws IOException, KeeperException, InterruptedException {        ZooKeeper zkCli = new ZooKeeper("os-1:2181,os-2:2181,os-3:2181", 2000, new Watcher() {            @Override            public void process(WatchedEvent event) {                System.out.println("节点:"+event.getPath()+"发生了事件;" + event.getState());            }        });        //获取 "/"根节点下的字节列表,并对"/"节点注册监听器        List<String> children = zkCli.getChildren("/", true);        for(String child:children) {            System.out.println(child);        }    }}