package CreateGroup;import java.io.IOException;import java.util.List;import java.util.concurrent.CountDownLatch;import org.apache.zookeeper.AsyncCallback;import org.apache.zookeeper.AsyncCallback.Children2Callback;import org.apache.zookeeper.AsyncCallback.ChildrenCallback;import org.apache.zookeeper.AsyncCallback.StatCallback;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;import org.apache.zookeeper.server.ConnectionBean;public class TestZkGroup implements Watcher {	private static final int SESSION_TIMEOUT = 5000;		private ZooKeeper zk;	private CountDownLatch connectedSignal = new CountDownLatch(2);	Childwatcher childwatcher = new Childwatcher(); 		private void getthreadname(String funname){		Thread current = Thread.currentThread();  		System.out.println(funname + " is call in  " + current.getName());	}		@Override	// 运行在另外一个线程 main-EventThread	public void process(WatchedEvent event) {		getthreadname("process");		System.out.println((event.getType()));  // 打印状态				if (event.getState() == KeeperState.SyncConnected){			connectedSignal.countDown();		}	}		// 测试自定义监听	public Watcher wh = new Watcher() {		public void process(WatchedEvent event) {			getthreadname("Watcher::process");			System.out.println("回调watcher实例： 路径" + event.getPath() + " 类型："			+ event.getType());		}	};		public void connect(String hosts) throws IOException, InterruptedException{		getthreadname("connect");		zk = new ZooKeeper(hosts, SESSION_TIMEOUT, wh); // 最后一个参数用this会调用自身的监听  wh 代表？		//connectedSignal.await(); // 主线程挂起	}		// 加入组(可以理解成一个创建本次连接的一个组)	public void join(String groupname, String meberName) throws KeeperException, InterruptedException{		 String path = "/" + groupname + "/" + meberName ;                		// EPHEMERAL断开将被删除		String createdpath = zk.create(path, null, Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL);		System.out.println("join : " + createdpath);	}	    public List<String> getChilds(String path) throws KeeperException, InterruptedException {          // TODO Auto-generated method stub          if (zk != null) {              // return zk.getChildren(path, false); // false表示没有设置观察         	//zk.getChildren(path, true, childwatcher.processResult, null);        	zk.getChildren( path, true, new AsyncCallback.Children2Callback() {				@Override				public void processResult(int rc, String path, Object ctx,						List<String> children, Stat stat) { // stat参数代表元数据					// TODO Auto-generated method stub					System.out.println("****");				  	for (int i = 0; i < children.size() - 1; i ++){		        		System.out.println("mempath = " + children.get(i) + stat);		        	}					}    }, null);        	        }          return null;      }  		public void create(String path) throws KeeperException, InterruptedException, IOException{		// Ids.OPEN_ACL_UNSAFE 开放式ACL，允许任何客户端对znode进行读写		// CreateMode.PERSISTENT 持久的znode，本次连接断开后还会存在，应该有持久化操作.		// PERSISTENT_SEQUENTIAL 持久化顺序，这个由zookeeper来保证				String createdpath = zk.create(path, null, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);		System.out.println("crateed : " + createdpath);    	}		private void close() throws InterruptedException{		if  (zk != null){			zk.close();		}	}		public static class Childwatcher implements Children2Callback{		public ChildrenCallback processResult;		@Override		public void processResult(int rc, String path, Object ctx,				List<String> children, Stat stat) {			// TODO Auto-generated method stub			System.out.println("**** path " + stat);		}	}		public void delete(String groupname) throws InterruptedException, KeeperException{				zk.delete(groupname, -1);	}		public Stat isexist(String groupname) throws InterruptedException, KeeperException{				return zk.exists(groupname, true); // this	}		 public void write(String path, String value)throws Exception{           Stat stat=zk.exists(path, false);           if(stat==null){               zk.create(path, value.getBytes("UTF-8"), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);           }else{                              zk.setData(path, value.getBytes("UTF-8"), -1);           }           }  	 	 public String read(String path,Watcher watch)throws Exception{           byte[] data=http://www.mamicode.com/zk.getData(path, watch, null);             "UTF-8");       }  	public static void main(String[] args) throws Exception {			String hosts = "localhost";		String groupname = "zktest" ;		String meberName = String.valueOf(System.currentTimeMillis());		String path = "/" + groupname;				// create		TestZkGroup test = new TestZkGroup();		//  连接		test.connect(hosts);		// 	    if (null != test.isexist(path)){	    	test.delete(path);	    }				test.isexist(path);        test.create(path);                test.isexist(path);        test.write(path, "test");                test.isexist(path);        String result = test.read(path, test.wh);        System.out.println(path + " value = "http://www.mamicode.com/+ result);"/" + "zktest" );        if (memlist != null){        	for (int i = 0; i < memlist.size() - 1; i ++){        		System.out.println("mempath = " + memlist.get(i));        	}        }	}}