java链接zookeeper

服务器通信以及跨平台通信中会遇到zookeeper这个东西，至于什么是zookeeper，google it！

为了测试这块的东西，必须要懂zookeeper工作原理，因此，本人整理了一下zookeeper的一般用法便于理解，以及更好的测试~~

package com.kiven.test;import java.io.IOException;import java.util.concurrent.CountDownLatch;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;import org.apache.zookeeper.Watcher.Event.KeeperState;public class Demo implements Watcher {          //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)    */     public void process(WatchedEvent event) {       // TODO Auto-generated method stub       if(event.getState()==KeeperState. SyncConnected){              countDownLatch.countDown();         }     }    public void close() throws InterruptedException{      zooKeeper.close();        }}=================================================================================================================================package com.kiven.test;import java.util.List;import org.apache.log4j.PropertyConfigurator;import org.apache.zookeeper.CreateMode;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.ZooDefs.Ids;public class MyTest extends Demo{         /**       *        *<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()){                   System. out.println(path+ "中没有节点" );              } else{                   System. out.println(path+ "中存在节点" );                   for(String child:list){                        System. out.println( "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[]){            PropertyConfigurator. configure("log4j.properties");             try {                      MyTest zkoperator = new MyTest();                zkoperator.connect( "172.16.3.9");              //          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( "/test", zktest.getBytes());            zkoperator.create( "/test/test1", zktest.getBytes());            System. out.println( "获取设置的信息：" +new String(zkoperator.getData("/test" )));                          System. out.println( "节点孩子信息:" );            zkoperator.getChild( "/test");                                zkoperator.close();            } catch (Exception e) {                e.printStackTrace();            }       }}