How is an observable object subclassed in java?

It can be subclassed to represent an object that the application wants to have observed. An observable object can have one or more observers. An observer may be any object that implements interface Observer.
Just so, what is the definition of an observable object in Java?
Class Observable. public class Observable extends Object This class represents an observable object, or "data" in the model-view paradigm. It can be subclassed to represent an object that the application wants to have observed. An observable object can have one or more observers. An observer may be any object that implements interface Observer.
Thereof, is the observable class deprecated in Java 11? Deprecated. This class and the Observer interface have been deprecated. The event model supported by Observer and Observable is quite limited, the order of notifications delivered by Observable is unspecified, and state changes are not in one-for-one correspondence with notifications.
Accordingly, is there support for observable as an abstract class in Java?
Java provides support for Observable as an abstract class and not an interface (Observable). It has the following methods These are very similar to the methods in the Subject interface we created when implementing Observer pattern in the last post. There is another important method called setChanged which I’ll explain in a moment.
Furthermore, can you add observable behavior to another class in Java?
Since there is no multiple inheritance in Java, we cannot add Observable behavior to an existing class that subclasses some other class. The setChanged method is protected. This means that to call this we have to subclass Observable. If we have composed Observable, we cannot call this method.

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