Observer (Java Platform SE 7 b138)

```
public interface Observer
```
A class can implement the Observer interface when it wants to be informed of changes in observable objects.

Since:

JDK1.0

See Also:
Observable

- Method Summary
  
  Methods
  Modifier and Type Method and Description
  
  void update(Observable o, Object arg)
  This method is called whenever the observed object is changed.

Methods
Modifier and Type	Method and Description
`void`	`update(Observable o, Object arg)` This method is called whenever the observed object is changed.

- Method Detail
  - update
```
void update(Observable o,
          Object arg)
```
    This method is called whenever the observed object is changed. An application calls an Observable object's notifyObservers method to have all the object's observers notified of the change.
    
    Parameters:
    o - the observable object.
    arg - an argument passed to the notifyObservers method.

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DRAFT ea-b138

Interface Observer

Method Summary

Method Detail

update