Curator Framework判断Zookeeper节点是临时节点还是持久化节点

待我称王封你为后i 2022-05-25 01:58 266阅读 0赞

Curator Framework客户端使用，请看上一篇博客《[Zookeeper客户端Curator Framework使用][Zookeeper_Curator Framework]》。

CuratorFramework类有一个判断节点是否存在的接口checkExists()，该接口返回一个org.apache.zookeeper.data.Stat对象，对象中有一个ephemeralOwner属性。

*  如果该节点是持久化节点，ephemeralOwner的值为0
 *  如果该节点是临时节点，ephemeralOwner的值大于0

示例，现在Zookeeper上有一个持久化节点(/chijiu )和一个临时节点(/linshi)。

**1、获取持久化节点(/chijiu )节点Stat对象**

**![20180506100128418][]**

**2、获取临时节点(/linshi )节点Stat对象**

**![20180506100032607][]**

**完整代码如下：**

引入jar包

![20180506100752728][]

测试代码

import org.apache.curator.RetryPolicy;
    import org.apache.curator.framework.CuratorFramework;
    import org.apache.curator.framework.CuratorFrameworkFactory;
    import org.apache.curator.retry.ExponentialBackoffRetry;
    import org.apache.zookeeper.CreateMode;
    import org.apache.zookeeper.data.Stat;
    
    /**
     * Created by wzj on 2018/5/3.
     */
    public class ZKTest
    {
    
        public static void main(String[] args) throws Exception
        {
            RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
    
            CuratorFramework client = CuratorFrameworkFactory.newClient("192.168.3.45:2181", retryPolicy);
    
            client.start();
    
    
            crateNode(client,"/linshi",CreateMode.EPHEMERAL,"");
            crateNode(client,"/chijiu",CreateMode.PERSISTENT,"");
    
            System.out.println(getNodeType(client,"/linshi"));
    
            System.out.println(getNodeType(client,"/chijiu"));
        }
    
        /**
         * 创建节点
         * @param client 客户端
         * @param path       路径
         * @param createMode 节点类型
         * @param data       节点数据
         * @return 是否创建成功
         */
        public static boolean crateNode(CuratorFramework client,String path, CreateMode createMode, String data)
        {
            try
            {
                client.create().withMode(createMode).forPath(path, data.getBytes());
            }
            catch (Exception e)
            {
                e.printStackTrace();
                return false;
            }
    
            return true;
        }
    
        /**
         * 判断节点是否是持久化节点
         * @param client 客户端
         * @param path 路径
         * @return null-节点不存在  | CreateMode.PERSISTENT-是持久化 | CreateMode.EPHEMERAL-临时节点
         */
        public static CreateMode getNodeType(CuratorFramework client,String path)
        {
            try
            {
                Stat stat = client.checkExists().forPath(path);
    
                if (stat == null)
                {
                    return null;
                }
    
                if (stat.getEphemeralOwner() > 0)
                {
                    return CreateMode.EPHEMERAL;
                }
    
                return CreateMode.PERSISTENT;
            }
            catch (Exception e)
            {
                e.printStackTrace();
    
                return null;
            }
        }
    
    }

[Zookeeper_Curator Framework]: https://blog.csdn.net/u010889616/article/details/80209629
[20180506100128418]: /images/20220525/0118e26a2218439287753ee7135d1f07.png
[20180506100032607]: /images/20220525/e7080e57486d47b098664d389da104e3.png
[20180506100752728]: /images/20220525/5eebcb4dd9c54f868f777ce4704f05be.png