Summary

In this chapter, we discussed the behavioral design patterns.

First, we covered the Chain of Responsibility pattern, which simplifies the management of complex processing flows, making it a valuable tool for enhancing flexibility and maintainability in software design.

Second, we went over the Command pattern, which encapsulates a request as an object, thereby allowing us to parameterize clients with queues, requests, and operations. It also allows us to support undoable operations. Although the most advertised feature of command by far is undo, it has more uses. In general, any operation that can be executed at the user’s will at runtime is a good candidate for using the Command pattern.

We looked at the Observer pattern, which helps with the separation of concerns, increasing decoupling between the publisher and subscribers. We have seen that observers are loosely coupled with the subject and can be added or removed dynamically.

Then, we went over the State...