ZooKeeper_6_Java操作ZK_删除节点

删除节点

同步删除节点

void org.apache.zookeeper.ZooKeeper.delete(String path, int version)

异步删除节点

void org.apache.zookeeper.ZooKeeper.delete(String path, int version, VoidCallback cb, Object ctx)

参数说明：

path	执行数据节点的节点路径
version	指定节点的版本数据，表明本次删除是针对该数据版本进行的
cb	注册一个异步回调函数
ctx	用于传递上下文信息的对象

同步删除节点Demo

public class TestDelete implements Watcher {

// 屏障，计数器
private static CountDownLatch downLatch = new CountDownLatch(1);

public static void main(String[] args) throws Exception {

ZooKeeper zookeeper = new ZooKeeper("10.0.227.66:2181", 5000, new TestDelete());

System.out.println("zookeeper.getState()1 : " + zookeeper.getState());

try {
downLatch.await();// 在计数器未归零之前，所有线程等待
} catch (Exception e) {
e.printStackTrace();
}

System.out.println("zookeeper.getState()2 : " + zookeeper.getState());

zookeeper.delete("/cyx", -1);
System.out.println("删除完成");

}

@Override
public void process(WatchedEvent event) {

System.out.println("receive watched event : " + event);

if (KeeperState.SyncConnected == event.getState()) {
downLatch.countDown();// 计数器-1
}

}

}
输出结果：
zookeeper.getState()1 : CONNECTING
receive watched event : WatchedEvent state:SyncConnected type:None path:null
zookeeper.getState()2 : CONNECTED
删除完成
这里就不贴ZooKeeper服务端的结果了..反正就是删掉了..

异步删除节点：

public class TestDelete implements Watcher {

// 屏障，计数器
private static CountDownLatch downLatch = new CountDownLatch(1);

public static void main(String[] args) throws Exception {

ZooKeeper zookeeper = new ZooKeeper("10.0.227.66:2181", 5000, new TestDelete());

System.out.println("zookeeper.getState()1 : " + zookeeper.getState());

try {
downLatch.await();// 在计数器未归零之前，所有线程等待
} catch (Exception e) {
e.printStackTrace();
}

System.out.println("zookeeper.getState()2 : " + zookeeper.getState());

zookeeper.delete("/cyx", -1, new myCallBack(), "123");
System.out.println("删除完成");

Thread.sleep(Integer.MAX_VALUE);

}

static class myCallBack implements VoidCallback {

@Override
public void processResult(int arg0, String arg1, Object arg2) {
System.out.println(arg0);
System.out.println(arg1);
System.out.println(arg2);
}

}

@Override
public void process(WatchedEvent event) {

System.out.println("receive watched event : " + event);

if (KeeperState.SyncConnected == event.getState()) {
downLatch.countDown();// 计数器-1
}

}

}
输出结果：
zookeeper.getState()1 : CONNECTING
receive watched event : WatchedEvent state:SyncConnected type:None path:null
zookeeper.getState()2 : CONNECTED
删除完成
0
/cyx
123

这个回调和上面创建节点的使用方式差不多耶...

不多说了...

自己体会....