zookeeper 客户端操作

代码

/**
 * 创建zk客户端
 * 实现循环监听的两个必要条件:1.程序不能结束2.递归调用监听器
 * @author tele
 *
 */
public class Demo {
    private int sessionTimeout = 2000;
    //多个节点用逗号隔开
    private String connectString="hadoop002:2181,hadoop003:2181";
    private ZooKeeper zkClient;
    
    /**
     * 初始化
     * @throws IOException
     */
    @Before
    public void init() throws IOException {
        zkClient = new ZooKeeper(connectString, sessionTimeout,new Watcher(){
            @Override
            public void process(WatchedEvent event) {
                try {
                    //实现循环监听
                    List<String> list = zkClient.getChildren("/",true);
                } catch (KeeperException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println(event.getType() + "	" + "path:" + event.getPath());
                
            }
        });
    }
    
    
    /**
     * 创建节点
     * @throws InterruptedException 
     * @throws KeeperException 
     */
    @Test
    public void createNode() throws KeeperException, InterruptedException {
        String nodeName = zkClient.create("/wycrencaiss","ok".getBytes(),Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT_SEQUENTIAL);
        System.out.println("创建的节点名称是-----" + nodeName);
    }
    
    
    
    /**
     * 获取节点
     * @throws InterruptedException 
     * @throws KeeperException 
     */
    @Test
    public void getNode() throws KeeperException, InterruptedException {
        List<String> list = zkClient.getChildren("/",true);
        for (String string : list) {
            System.out.println(string);
        }
        
        Thread.sleep(Long.MAX_VALUE);
    }
    
    
    /**
     * 判断节点是否存在
     * @throws InterruptedException 
     * @throws KeeperException 
     */
    @Test
    public void isExist() throws KeeperException, InterruptedException {
        
        Stat stat = zkClient.exists("/wyc",true);
        System.out.println(stat==null?"not exist":"exist");
        Thread.sleep(Long.MAX_VALUE);
    }
}

maven

<dependency>
      <groupId>org.apache.zookeeper</groupId>
      <artifactId>zookeeper</artifactId>
      <version>3.4.10</version>
</dependency>
<dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
</dependency>