IObserver (CMS API 15.5.0 API)

All Superinterfaces:

EventListener, org.apache.wicket.util.io.IClusterable, Serializable

All Known Implementing Classes:

AbstractListingPlugin, AbstractRenderService, BreadcrumbPlugin, BrowserPlugin, CompatibilityWorkflowPlugin, ExpandCollapseListingPlugin, JcrTreeModel, ListRenderService, ListViewPlugin, ListViewService, Observer, PanelPluginPerspective, Perspective, RenderPlugin, RenderService, TabsContainerService, TabsPlugin, TabsPlugin.Tab
```
public interface IObserver<T extends IObservable>
extends EventListener, org.apache.wicket.util.io.IClusterable
```
This interface defines the contract for a service that updates its internal state in response to changes in an observable object (IObservable). Instances should be registered as a service (IPluginContext.registerService(IClusterable, String)) with name IObserver.class.getName(). The observer registry will notify the observer of any events sent by the observable.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`T`	`getObservable()`	The observable that the observer is interested in.
`void`	`onEvent(Iterator<? extends IEvent<T>> events)`	Callback that is invoked when the observable sends events.

- Method Detail
  - getObservable
```
T getObservable()
```
    The observable that the observer is interested in. This observable may not change, w.r.t. the IObservable.equals(java.lang.Object) method, while the observer is registered.
  - onEvent
```
void onEvent(Iterator<? extends IEvent<T>> events)
```
    Callback that is invoked when the observable sends events. The iterator is guaranteed to be non-empty.