|Due at Friday, June 26th, 23:59|
Due to legal reasons, only movies rated suitable for persons under the age of 18 are allowed to be viewed publicly on the MMM web portal. Because of this, we want a way to establish an access control proxy for the list of movies.
For this task, you will need to install RAP1) into Eclipse.
We've created a simple chat application called “Chatter” with RAP.
Check out the “Chatter” project from your repository.
The application has a certain problem: Once a client starts it, the messages are loaded from the shared MessageHistory, but afterwards, nothing is updated. You can't even see your own messages!
Your task is to implement an Observer Pattern to solve this problem.
In this task you will learn how to use the Abstractness-Stability-Diagram to decide whether a certain design pattern is appropriate or not. As the pattern wasn't covered in the lecture we quickly introduce it here: