In SOLID, what is the distinction between SRP and ISP? (Single Responsibility Principle and Interface Segregation Principle)

Question

How does the SOLID \"Interface Segregation Principle\" differ from \"Single Responsibility Principle\"?

The Wikipedia entry for SOLID says that

IS

Answer 1

SRP is concerned with what a module does, and how it is done, disallowing any mix of abstraction levels. Basically, as long as a component can be extensively defined with a single sentence, it will not break SRP.

On the other hand ISP is concerned with how a module should be consumed, whether it makes sense to consume just part of the module, while ignoring some aspect.

As an example of a code that keeps the spirit or SRP, but can break ISP is the Facade pattern. It has a single responsibility, "providing simplified access to a larger subsystem", but if the underlying subsystem needs to expose wildly different thinks, it does break ISP.

That said, usually when a piece of code breaks a SOLID principle, it often breaks the whole lot. Concrete examples that break a specific principle, while preserving the rest are rare in the wild.