Component Cohesion/CCP

• is the component form of the Single Responsability Principle

• separate classes into different components if they change for different reasons

  Gather together those things that change at the same times and for the same reasons. Separate those things that change at different times or for different reasons.

Relation to cohesion metrics

The CCP reflects the spirit of high cohesion: modules that change together belong together. It operationalises temporal and communicational cohesion at the component level — grouping code that responds to the same change forces, rather than just code that is structurally similar.

In the modularity framework of Fundamentals of Software Architecture, CCP is a design-level expression of the same principle captured by component cohesion metrics: high cohesion (code that belongs together stays together) and low coupling (code that changes independently stays separate).

Resources

• 2026-06-16 ◦ Fundamentals of Software Architecture, 2E — Richards & Ford — Ch. 3: cohesion as a modularity metric; the CCP principle is implicitly applied in the discussion of why splitting cohesive modules increases coupling; cross-linked to FSA’s cohesion types (especially temporal and communicational cohesion)