十九curator recipes之PathChildrenCache

Posted 2021-02-03 lay2017

简介

curator可以监听路径下子节点的变更操作，如创建节点，删除节点

官方文档：http://curator.apache.org/curator-recipes/path-cache.html

javaDoc：http://curator.apache.org/apidocs/org/apache/curator/framework/recipes/cache/PathChildrenCache.html

代码示例

import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.cache.PathChildrenCache;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheEvent;
import org.apache.curator.framework.recipes.cache.PathChildrenCacheListener;
import org.apache.curator.retry.ExponentialBackoffRetry;

public class PathChildrenCacheDemo {
    private static CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181", new ExponentialBackoffRetry(3000, 1));
    private static String path = "/path/test/0001";
    static {
        client.start();
    }

    public static void main(String[] args) throws Exception {
        PathChildrenCache pathChildrenCache = new PathChildrenCache(client, path, true);
        pathChildrenCache.getListenable().addListener(new PathChildrenCacheListener() {
            @Override
            public void childEvent(CuratorFramework curatorFramework, PathChildrenCacheEvent pathChildrenCacheEvent) throws Exception {
                System.out.println(pathChildrenCacheEvent.toString());
            }
        });
        pathChildrenCache.start();
        System.out.println("started");
        Thread.sleep(2000);
        System.out.println("sleep end");
        client.create().forPath(path + "/000002");
        client.delete().forPath(path + "/000002");
        System.out.println("updated");
        pathChildrenCache.close();
        System.out.println("close");
        Thread.sleep(50000);
        client.close();
    }
}