interfacesintended

Interfacesintended is a term used in software engineering to describe a design approach that emphasizes creating interfaces whose members reveal and constrain the intended use by clients. The goal is to produce clear, predictable contracts that align with how the software is meant to be used, reducing ambiguity and the likelihood of misuse or leakage of implementation details. It is not a formal standard or widely codified methodology, but rather a guiding principle encountered in discussions about API and library design.

Key ideas include naming methods after concrete tasks, exposing only operations that clients need, and avoiding methods that reflect the internal structure or construction of the implementation. Interfaces should express intent, not implementation. This leads to more stable, readable code and easier testing, as clients interact with well-defined capabilities rather than low-level mechanisms.

Practical guidelines involve identifying the primary tasks clients must perform, splitting large interfaces into smaller task-specific ones, and favoring narrow, cohesive interfaces in the spirit of the Interface Segregation Principle. Documentation should accompany interfaces to clarify intended behavior and invariants. For example, a data repository interface might declare addItem, removeItem, findById, and listAll, with no access to internal storage details or assumptions about how data is indexed, unless required by clients.

Relation to broader topics includes alignment with API design, consumer-driven contracts, and design by contract. Some criticisms note that overemphasizing intent can lead to excessive fragmentation or under-specification if not balanced with actual use cases. See also interface design, API design, and the Interface Segregation Principle.