4.2 创建客户端

package com.atguigu.zk;

import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;

public class ZKClientDemo {

    private String conn = "hadoop201:2181,hadoop202:2181,hadoop203:2181";
    private int sessionTime = 2000;
    private ZooKeeper zkClient;

    @Test
    public void init() throws IOException {
        /*
        参数1: 连接字符串.  是由zookeeper服务器组成格式. 多个服务器之间用逗号隔开
            host1:port,host2:port, ....
        参数2: session超时时间, 用毫秒值来表示
        参数3: 监听器对象. 监听zookeeper状态的变化.
         */
        zkClient = new ZooKeeper(conn, sessionTime, new Watcher() {
            // 收到事件之后的回调函数.(用户的业务逻辑)
            @Override
            public void process(WatchedEvent watchedEvent) {
                System.out.println(watchedEvent.getPath()
                        + " --- " + watchedEvent.getType()
                        + " --- " + watchedEvent.getState());

            }
        });
    }
}