Java实现与ZooKeeper的连接
序言
续上一篇的 /** * AbstractZooKeeper.java * 版权所有(C) 2013 * 创建:cuiran 2013-01-16 14:59:44 */package com.zoo.demo;import java.io.IOException;import java.util.concurrent.CountDownLatch;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;import org.apache.zookeeper.Watcher.Event.KeeperState;/** * TODO * @author cuiran * @version TODO */public class AbstractZooKeeper implements Watcher {private static Log log = LogFactory.getLog(AbstractZooKeeper.class.getName());//缓存时间 private static final int SESSION_TIME = 2000; protected ZooKeeper zooKeeper; protected CountDownLatch countDownLatch=new CountDownLatch(1); public void connect(String hosts) throws IOException, InterruptedException{ zooKeeper = new ZooKeeper(hosts,SESSION_TIME,this); countDownLatch.await(); } /* (non-Javadoc) * @see org.apache.zookeeper.Watcher#process(org.apache.zookeeper.WatchedEvent) */@Overridepublic void process(WatchedEvent event) {// TODO Auto-generated method stubif(event.getState()==KeeperState.SyncConnected){countDownLatch.countDown();}}public void close() throws InterruptedException{ zooKeeper.close(); } }
然后写一些操作和main方法
/** * ZooKeeperOperator.java * 版权所有(C) 2013 * 创建:cuiran 2013-01-16 15:03:40 */package com.zoo.demo;import java.util.Arrays;import java.util.List;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.apache.zookeeper.CreateMode;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.ZooDefs.Ids;/** * TODO * @author cuiran * @version TODO */public class ZooKeeperOperator extends AbstractZooKeeper {private static Log log = LogFactory.getLog(ZooKeeperOperator.class.getName());/** * *<b>function:</b>创建持久态的znode,比支持多层创建.比如在创建/parent/child的情况下,无/parent.无法通过 *@author cuiran *@createDate 2013-01-16 15:08:38 *@param path *@param data *@throws KeeperException *@throws InterruptedException */public void create(String path,byte[] data)throws KeeperException, InterruptedException{/** * 此处采用的是CreateMode是PERSISTENT 表示The znode will not be automatically deleted upon client's disconnect. * EPHEMERAL 表示The znode will be deleted upon the client's disconnect. */ this.zooKeeper.create(path, data, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);}/** * *<b>function:</b>获取节点信息 *@author cuiran *@createDate 2013-01-16 15:17:22 *@param path *@throws KeeperException *@throws InterruptedException */public void getChild(String path) throws KeeperException, InterruptedException{ try{List<String> list=this.zooKeeper.getChildren(path, false);if(list.isEmpty()){log.debug(path+"中没有节点");}else{log.debug(path+"中存在节点");for(String child:list){log.debug("节点为："+child);}}}catch (KeeperException.NoNodeException e) {// TODO: handle exception throw e; }}public byte[] getData(String path) throws KeeperException, InterruptedException { return this.zooKeeper.getData(path, false,null); } public static void main(String[] args) { try { ZooKeeperOperator zkoperator = new ZooKeeperOperator(); zkoperator.connect("192.168.0.138"); byte[] data = new byte[]{'a','b','c','d'}; // zkoperator.create("/root",null); // System.out.println(Arrays.toString(zkoperator.getData("/root"))); // // zkoperator.create("/root/child1",data); // System.out.println(Arrays.toString(zkoperator.getData("/root/child1"))); // // zkoperator.create("/root/child2",data); // System.out.println(Arrays.toString(zkoperator.getData("/root/child2"))); String zktest="ZooKeeper的Java API测试"; zkoperator.create("/root/child3", zktest.getBytes()); log.debug("获取设置的信息："+new String(zkoperator.getData("/root/child3"))); System.out.println("节点孩子信息:"); zkoperator.getChild("/root"); zkoperator.close(); } catch (Exception e) { e.printStackTrace(); } }}
最后运行结果：
2013-01-16 15:26:04:INFO org.apache.zookeeper.ZooKeeper - Client environment:user.name=Administrator2013-01-16 15:26:04:INFO org.apache.zookeeper.ZooKeeper - Client environment:user.home=C:\Documents and Settings\Administrator2013-01-16 15:26:04:INFO org.apache.zookeeper.ZooKeeper - Client environment:user.dir=D:\workspace\stormdemo12013-01-16 15:26:04:INFO org.apache.zookeeper.ZooKeeper - Initiating client connection, connectString=192.168.0.138 sessionTimeout=2000 watcher=com.zoo.demo.ZooKeeperOperator@ca83272013-01-16 15:26:04:INFO org.apache.zookeeper.ClientCnxn - Opening socket connection to server /192.168.0.138:21812013-01-16 15:26:13:INFO org.apache.zookeeper.ClientCnxn - Socket connection established to 192.168.0.138/192.168.0.138:2181, initiating session2013-01-16 15:26:13:INFO org.apache.zookeeper.ClientCnxn - Session establishment complete on server 192.168.0.138/192.168.0.138:2181, sessionid = 0x13c3c5224cc0003, negotiated timeout = 40002013-01-16 15:26:13:DEBUG com.zoo.demo.ZooKeeperOperator - 获取设置的信息：ZooKeeper的Java API测试节点孩子信息:2013-01-16 15:26:13:DEBUG com.zoo.demo.ZooKeeperOperator - /root中存在节点2013-01-16 15:26:13:DEBUG com.zoo.demo.ZooKeeperOperator - 节点为：child12013-01-16 15:26:13:DEBUG com.zoo.demo.ZooKeeperOperator - 节点为：child32013-01-16 15:26:13:DEBUG com.zoo.demo.ZooKeeperOperator - 节点为：child22013-01-16 15:26:13:INFO org.apache.zookeeper.ZooKeeper - Session: 0x13c3c5224cc0003 closed2013-01-16 15:26:13:INFO org.apache.zookeeper.ClientCnxn - EventThread shut down
针对出现的中文乱码看采用下面的处理即可：
String zktest="ZooKeeper的Java API测试"; zkoperator.create("/root/child5", zktest.getBytes("utf-8")); log.debug("获取设置的信息："+new String(zkoperator.getData("/root/child5"),"utf-8"));