ZooKeeper之java客户端访问-入门介绍(一)

2014-11-24 00:44:48 · 作者: · 浏览: 0

上篇简单的介绍了单点部署ZooKeeper及节点管理。


这里介绍下如何通过java客户端进行各个节点的管理。


具体就不一一介绍,相信从代码的注释中就可以看明白

首先创建一个zookeeper的基础类,里面包含了基本的节点管理方法,如下:

package com.zktest.newtest;

import java.io.IOException;
import java.util.List;
import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;

public class BaseZookeeper implements Watcher
{

	public ZooKeeper zooKeeper;

	private static final int SESSION_TIME_OUT = 2000;

	private CountDownLatch countDownLatch = new CountDownLatch(1);

	/**
	 * 连接zookeeper
	 * 
	 * @param host
	 * @throws IOException
	 * @throws InterruptedException
	 */
	public void connectZookeeper(String host) throws IOException,
			InterruptedException
	{
		zooKeeper = new ZooKeeper(host, SESSION_TIME_OUT, this);
		countDownLatch.await();
		System.out.println("zookeeper connect ok");

	}

	/**
	 * 实现watcher的接口方法,当连接zookeeper成功后,zookeeper会通过此方法通知watcher
* 此处为如果接受到连接成功的event,则countDown,让当前线程继续其他事情。 */ @Override public void process(WatchedEvent event) { if (event.getState() == KeeperState.SyncConnected) { System.out.println("watcher received event"); countDownLatch.countDown(); } } /** * 根据路径创建节点,并且设置节点数据 * @param path * @param data * @return * @throws KeeperException * @throws InterruptedException */ public String createNode(String path, byte[] data) throws KeeperException, InterruptedException { return this.zooKeeper.create(path, data, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); } /** * 根据路径获取所有孩子节点 * * @param path * @return * @throws KeeperException * @throws InterruptedException */ public List getChildren(String path) throws KeeperException, InterruptedException { return this.zooKeeper.getChildren(path, false); } public Stat setData(String path, byte [] data, int version) throws KeeperException, InterruptedException { return this.zooKeeper.setData(path, data, version); } /** * 根据路径获取节点数据 * * @param path * @return * @throws KeeperException * @throws InterruptedException */ public byte[] getData(String path) throws KeeperException, InterruptedException { return this.zooKeeper.getData(path, false, null); } /** * 删除节点 * * @param path * @param version * @throws InterruptedException * @throws KeeperException */ public void deletNode(String path, int version) throws InterruptedException, KeeperException { this.zooKeeper.delete(path, version); } /** * 关闭zookeeper连接 * * @throws InterruptedException */ public void closeConnect() throws InterruptedException { if (null != zooKeeper) { zooKeeper.close(); } } }

创建客户端进行测试,代码如下:

package com.spg.zktest.newtest;

import java.io.IOException;
import java.util.Arrays;
import java.util.List;

import org.apache.zookeeper.KeeperException;

public class Client
{

	/**
	 * @param args
	 * @throws InterruptedException 
	 * @throws IOException 
	 * @throws KeeperExceptio