Design Patterns in 1 minute: Chain of Responsibility #5
Classification: Behavioral
The Chain of Responsibility design pattern allows decoupling control flow from the receiver (entrypoint) by passing the responsibility to a chain of handlers that can decide how to handle the request and whether to pass it to the next handler in the chain.
The Problem
Imagine you have a sequence of steps and complex conditions to execute, and these steps evolve weekly with new instructions and behaviors.
For example, consider form validation: depending on certain fields, we must perform different types of behavior and checks. You can see how this sequence of steps can quickly become complex and lead to "spaghetti code."
How can we solve this problem?
The Solution
The idea here is to create a common interface for all steps, allowing the input data to be passed through one of its methods.
With the interface in place, each step should be divided into a specific class that receives the next step (if it exists).
After implementation, simply connect all classes in the expected order and run your code.