#Srp single responsibility principle code

Separation of Concerns (SoC) is a more versatile term - it can be applied at the system level or at lower levels such as classes (or even the methods within a class) After applying each of these principles, your context becomes more reusable, maintainable, robust, readable.As, a way to know that a class has more than one responsibility is if you can extract another responsibility(concern) from that class. SoC is a good design principle to cope complexity, such as abstraction whereas to reach single responsible classes you can use SoC principle as a great solution. The concept of SRP is based on the cohesion (high cohesion), whereas SoC is close to Molecularity, divide and conquer (D&C). In other side, SoC is a design principle for separating a context into distinct sections, such that each section addresses a separate concern(what not how), as there are a lot of tools (for example classes, functions, modules, packages. The SRP is about the quality of (how not what) dividing your domain into cohesive classes which have just one responsibility (one reason to change). The SRP is at the class level, but SoC is in each computer program, abstraction. I tried to draw a comparison between Separation of concerns(SoC) and Single Responsibility Principle(SRP). To the original question, the minor difference between the SRP and SoC is that Martin refined the term concerns to refer to people.

#Srp single responsibility principle code

And you don’t want to confuse those people, or yourself, by mixing together the code that many different people care about for different reasons. However, as you think about this principle, remember that the reasons for change are people. We want to increase the cohesion between things that change for the same reasons, and we want to decrease the coupling between those things that change for different reasons. If you think about this you’ll realize that this is just another way to define cohesion and coupling. Separate those things that change for different reasons. Gather together the things that change for the same reasons. Martin consolidated their ideas into the SRP.Īnother wording for the Single Responsibility Principle is: Martin's inspiration for the SRP was drawn from David Parnas, Edsger Dijkstra (who coined the term Separation of Concerns) and Larry Constantine (who coined the terms Coupling and Cohesion).

Since none of the previous answers quote Robert Martin, who created the Single Responsibility Principle, I think a more authoritative answer is needed here. The point is it will lead to a better codebase and more stable software. It just means a general principle of splitting out code into isolated parts. It doesn't mean going too far and having only one seven line method in each class, for example. SRP is a principle, not a rule, so you don't have to (read: can't/shouldn't) follow it religiously to the extreme. For the same reasons.Īlso, even at a method level, split large methods out into smaller methods. Instead of putting dozens of methods in a single class, split the code out into several. The two aren't horrifically intertwined.Īt a lower level, this should be applied to classes too. That way, the modification of a view can be done independently of a model. The codebase is split out into isolated models, views and controllers. MVC is an architectural pattern promoting SRP and SoC. This is applied at the module level, e.g. This allows multiple developers to work on different parts without affecting each other, it also allows a single developer to modify one isolated part without breaking another. That idea is simply to split your codebase into loosely coupled, isolated parts. The biggest problem is people get so caught up in wanting to know exactly what a 'concern' and 'responsibility' are, that they perhaps miss the important idea behind SRP and SoC. Sure, you can get bogged down in an academic discussion trying to tease out some kind of difference between the two, but why? For all intents and purposes, they describe the same thing. The Single Responsibility Principle and Separation of Concerns are really the same thing.