org.apache.zookeeper

Interface Watcher

All Known Subinterfaces:

ServerWatcher

All Known Implementing Classes:

ControllableConnection, DumbWatcher, NettyServerCnxn, NIOServerCnxn, ServerCnxn

@InterfaceAudience.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 is returned then the server must be updated to support this feature.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Watcher.Event This interface defines the possible states an Event may represent
static class	Watcher.WatcherType Enumeration of types of watchers

Method Summary

Modifier and Type	Method and Description
void	process(WatchedEvent event)

Method Detail

process

void process(WatchedEvent event)