zookeeper实现HA入门案例

package com.zhileiedu.zk;

import java.util.Random;

import javax.net.ssl.SSLEngineResult.Status;

import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.ZooDefs.Ids;

public class T {

static String status = "ACTIVE";

public static void main(String[] args) throws Exception {
	String connectString = "192.168.23.157:2181,192.168.23.157:2182,192.168.23.157:2183";
	ZooKeeper zk = new ZooKeeper(connectString, 5000, null);
	String IP = "202.106.29.138";
	String port = new Random().nextInt(500)+"";
	if(zk.exists("/zk01", new MasterWatcher()) != null) { // 节点已经创建
		status = "STANDBY";
	} else {
		zk.create("/zk01", (IP + ":"+port).getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL);
		status = "ACTIVE";
		System.out.println("启动active");
	}
	
	Thread.sleep(Integer.MAX_VALUE);
	
}


static class MasterWatcher implements Watcher {

	public void process(WatchedEvent e ) {
		// TODO Auto-generated method stub
		if (e.getType() == EventType.NodeDeleted) {
			status = "ACTIVE";
			System.out.println("切换为active");
		}
	}
	
}

}