Behavioral OOP Patterns In Dart

A continuation of examining OOP patterns in Dart. I previously covered, Creational OOP:

Dart Beginning OOP Patterns, Creational

And I covered Structural:

Dart Structural OOP Patterns

This time around, let’s talk about behavioral OOP patterns.

Chain Of Responsibility

In object-oriented design, the chain-of-responsibility pattern is a design pattern consisting of a source of command objects and a series of processing objects. Each processing object contains logic that defines the types of command objects that it can handle; the rest are passed to the next processing object in the chain. A mechanism also exists for adding new processing objects to the end of this chain. Thus, the chain of responsibility is an object-oriented version of the if … else if … else if ……. else … endif idiom, with the benefit that the condition-action blocks can be…