Interface Design

What is the Interface Segregation Principle?

The Interface Segregation Principle (the 'I' in SOLID) states that no client should be forced to depend on methods it does not use, so large interfaces should…

What is a Tightly Coupled System?

A tightly coupled system is one where classes or modules depend heavily on each other’s concrete internal details, so a change in one nearly always forces a ch…

What is a Loosely Coupled System?

A loosely coupled system is one where classes interact through stable abstractions like interfaces rather than concrete implementations, so a class can be swap…

Adapter vs Bridge Pattern

The Adapter pattern converts an existing incompatible interface into one a client expects, applied after the fact to make unrelated classes work together, whil…

What is a Fat Interface in OOP?

A fat interface is an interface that declares too many unrelated methods, forcing implementing classes to provide (or stub out) behavior they don’t actually ne…

What is Interface Pollution in OOP?

Interface pollution is the ongoing design mistake of adding methods to an existing shared interface that are only relevant to some implementers, gradually turn…

What is a Role Interface in OOP?

A role interface is a small, focused interface that describes one specific behavior or capability a client depends on, rather than the full public surface of a…

What is Nominal Typing?

Nominal typing is a type-compatibility rule where two types are considered compatible only if one explicitly declares itself to be, or to extend/implement, the…

What is Structural Typing?

Structural typing is a type-compatibility rule where two types are considered compatible if they expose the same shape — the same members with compatible signa…

What is a Hollow Abstraction in OOP?

A hollow abstraction is an interface or abstract class that exists in a codebase without providing any real behavioral contract or design value, typically beca…