What is the Observer Pattern in Java?

What is the Observer Pattern in Java?

The Observer Pattern is a behavioral design pattern that allows an object, known as the subject, to maintain a list of its dependents, called observers, and notify them of any state changes.

Can you give me an example of how to implement it?

Sure! In Java, you can create a Subject class that maintains a list of observers and has methods to attach, detach, and notify them. Each observer implements an interface with an update method.

What are some use cases for the Observer Pattern?

Common use cases include implementing event handling systems, such as in GUI frameworks, and in scenarios where a change in one object requires updates in others.

Are there any drawbacks to using the Observer Pattern?

Yes, one drawback is that it can lead to memory leaks if observers are not properly removed, as they may hold references to the subject.