向Zookeeper中注册内容以及从zookeeper中发现内容

一、向Zookeeper中注册内容

新建项目ZookeeperClient

1 创建/demo

使用zookeeper的客户端命令工具创建/demo

./zkCli.sh
create /demos

2 添加依赖

    
        org.apache.zookeeper
        zookeeper
        3.5.5
    

3 编写代码

创建类com.msb.MyApp。

ZooDefs.Ids.OPEN_ACL_UNSAFE 表示权限。

CreateMode.PERSISTENT_SEQUENTIAL 永久存储，文件内容编号递增。

public static void main(String [] args){
    try {
        ZooKeeper zookeeper = new ZooKeeper("192.168.32.128:2181", 10000, new Watcher() {
            @Override
            public void process(WatchedEvent watchedEvent) {
                System.out.println("获取连接");
            }
        });
        String content = zookeeper.create("/demo/nn", "content".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT_SEQUENTIAL);
        System.out.println("content"+content);
    } catch (IOException e) {
        e.printStackTrace();
    } catch (KeeperException e) {
        e.printStackTrace();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}

4 查看上传数据

ls -R / :查看列表

get /demo/nn0000000002 :查看内容

二、 从zookeeper中发现内容

在原有项目中新建一个类，类中编写主方法。

public static void main(String[] args) {
    try {
        ZooKeeper zookeeper = new ZooKeeper("192.168.32.128:2181", 10000, new Watcher() {
            @Override
            public void process(WatchedEvent watchedEvent) {
                System.out.println("获取连接");
            }
        });
        //获取列表
        List list = zookeeper.getChildren("/demo", false);
        for (String child : list) {
            byte[] result = zookeeper.getData("/demo/" + child, false, null);
            System.out.println(new String(result));
        }
    } catch (IOException e) {
        e.printStackTrace();
    } catch (KeeperException e) {
        e.printStackTrace();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}