Observable (Pravega API)

Type Parameters:

T - The type of event that is to be observed.

All Known Implementing Classes:

AbstractNotifier, AbstractPollingNotifier, EndOfDataNotifier, SegmentNotifier
```
public interface Observable<T>
```
This represents an observable notification.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`java.lang.String`	`getType()`	Get the notification type.
`void`	`registerListener(Listener<T> listener)`	Register listener for notification type T.
`void`	`unregisterAllListeners()`	Remove all listeners for a given type.
`void`	`unregisterListener(Listener<T> listener)`	Remove a listener.

- Method Detail
  - registerListener
```
void registerListener(Listener<T> listener)
```
    Register listener for notification type T. Multiple listeners can be added for the same type.
    
    Parameters:
    
    listener - This is the listener which will be invoked incase of an Notification.
  - unregisterListener
```
void unregisterListener(Listener<T> listener)
```
    Remove a listener.
    
    Parameters:
    
    listener - the listener which needs to be removed.
  - unregisterAllListeners
```
void unregisterAllListeners()
```
    Remove all listeners for a given type.
  - getType
```
java.lang.String getType()
```
    Get the notification type.
    
    Returns:
    
    Notification type.