Interface Watcher

All Known Implementing Classes:
ControllableConnection, DumbWatcher, InstanceContainer, InstanceManager, NettyServerCnxn, NIOServerCnxn, ServerCnxn, SimpleClient, SimpleSysTest, ZooInspectorManagerImpl.NodeWatcher

@Public public interface Watcher
This interface specifies the public interface an event handler class must implement. A ZooKeeper client will get various events from the ZooKeeper server it connects to. An application using such a client handles these events by registering a callback object with the client. The callback object is expected to be an instance of a class that implements Watcher interface. When process(org.apache.zookeeper.WatchedEvent) is triggered by a watch firing, such as Watcher.Event.EventType.NodeDataChanged, WatchedEvent.getZxid() will return the zxid of the transaction that caused said watch to fire. If -1L is returned then the server must be updated to support this feature.
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    This interface defines the possible states an Event may represent
    static enum 
    Enumeration of types of watchers
  • Method Summary

    Modifier and Type
    Method
    Description
    void