java连接ZK的基本操作

package com;

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{

private ZooKeeper zookeeper;
/**
* 超时时间
*/
private static final int SESSION_TIME_OUT = 2000;
private CountDownLatch countDownLatch = new CountDownLatch(1);
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
System.out.println("Watch received event");
countDownLatch.countDown();
}
}




/**连接zookeeper
* @param host
* @throws Exception
*/
public void connectZookeeper(String host) throws Exception{
zookeeper = new ZooKeeper(host, SESSION_TIME_OUT, this);
countDownLatch.await();
System.out.println("zookeeper connection success");
}

/**
* 创建节点
* @param path
* @param data
* @throws Exception
*/
public String createNode(String path,String data) throws Exception{
return this.zookeeper.create(path, data.getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
}

/**
* 获取路径下所有子节点
* @param path
* @return
* @throws KeeperException
* @throws InterruptedException
*/
public List<String> getChildren(String path) throws KeeperException, InterruptedException{
List<String> children = zookeeper.getChildren(path, false);
return children;
}

/**
* 获取节点上面的数据
* @param path 路径
* @return
* @throws KeeperException
* @throws InterruptedException
*/
public String getData(String path) throws KeeperException, InterruptedException{
byte[] data = zookeeper.getData(path, false, null);
if (data == null) {
return "";
}
return new String(data);
}

/**
* 设置节点信息
* @param path 路径
* @param data 数据
* @return
* @throws KeeperException
* @throws InterruptedException
*/
public Stat setData(String path,String data) throws KeeperException, InterruptedException{
Stat stat = zookeeper.setData(path, data.getBytes(), -1);
return stat;
}

/**
* 删除节点
* @param path
* @throws InterruptedException
* @throws KeeperException
*/
public void deleteNode(String path) throws InterruptedException, KeeperException{
zookeeper.delete(path, -1);
}

/**
* 获取创建时间
* @param path
* @return
* @throws KeeperException
* @throws InterruptedException
*/
public String getCTime(String path) throws KeeperException, InterruptedException{
Stat stat = zookeeper.exists(path, false);
return String.valueOf(stat.getCtime());
}

/**
* 获取某个路径下孩子的数量
* @param path
* @return
* @throws KeeperException
* @throws InterruptedException
*/
public Integer getChildrenNum(String path) throws KeeperException, InterruptedException{
int childenNum = zookeeper.getChildren(path, false).size();
return childenNum;
}
/**
* 关闭连接
* @throws InterruptedException
*/
public void closeConnection() throws InterruptedException{
if (zookeeper != null) {
zookeeper.close();
}
}

}

测试代码：

public class Demo {

public static void main(String[] args) throws Exception {
BaseZookeeper zookeeper = new BaseZookeeper();
zookeeper.connectZookeeper("192.168.0.1:2181");

List<String> children = zookeeper.getChildren("/");
System.out.println(children);
}

}