{"id":"decoupling-topology-composition-based","text":"The four sender-receiver decoupling patterns (Command, Observer, Mediator, Chain of Responsibility) all achieve decoupling through object composition rather than inheritance, confirming that behavioral flexibility in communication requires composition as its assembly mechanism — each pattern reifies a different communication topology (request, broadcast, hub, chain) as a composed object.","truth_value":"IN","source":"","source_url":"","source_hash":"","justifications":[{"type":"SL","antecedents":["four-decoupling-patterns-topology","behavioral-patterns-favor-composition"],"outlist":[],"label":"The decoupling topology (depth-1) is enabled by composition preference (depth-1) — topology and mechanism unify"}],"dependents":["behavioral-modification-bifurcates-wrapping-and-decoupling","complete-decoupling-via-composition","composition-centric-design-paradigm","coupling-management-complete-two-dimensions","coupling-management-covers-boundary-and-behavioral","observer-mediator-complete-communication","srp-resolves-decoupling-topology-choice"],"metadata":{"source_type":"derived","review_result":"invalid"},"created_at":"2026-06-17T17:55:06+00:00","updated_at":"2026-06-18T06:15:08+00:00","reviewed_at":"2026-06-18T06:15:08+00:00","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"decoupling-topology-composition-based","truth_value":"IN","reason":"SL justification valid","antecedents":["four-decoupling-patterns-topology","behavioral-patterns-favor-composition"],"label":"The decoupling topology (depth-1) is enabled by composition preference (depth-1) — topology and mechanism unify"},{"node":"four-decoupling-patterns-topology","truth_value":"IN","reason":"SL justification valid","antecedents":["four-patterns-decouple-senders-receivers","command-decouples-invoker-from-receiver","gof-mediator-replaces-many-to-many-with-one-to-many","chain-of-responsibility-implicit-receiver","gof-observer-intent-one-to-many-dependency"],"label":"Decoupling patterns span a topology from reified request to implicit broadcast"},{"node":"four-patterns-decouple-senders-receivers","truth_value":"IN","reason":"premise"},{"node":"command-decouples-invoker-from-receiver","truth_value":"IN","reason":"premise"},{"node":"gof-mediator-replaces-many-to-many-with-one-to-many","truth_value":"IN","reason":"premise"},{"node":"chain-of-responsibility-implicit-receiver","truth_value":"IN","reason":"premise"},{"node":"gof-observer-intent-one-to-many-dependency","truth_value":"IN","reason":"premise"},{"node":"behavioral-patterns-favor-composition","truth_value":"IN","reason":"SL justification valid","antecedents":["behavioral-patterns-class-vs-object","behavioral-patterns-encapsulate-variation","favor-composition-over-inheritance"],"label":"Behavioral object patterns are composition-over-inheritance put into practice"},{"node":"behavioral-patterns-class-vs-object","truth_value":"IN","reason":"premise"},{"node":"behavioral-patterns-encapsulate-variation","truth_value":"IN","reason":"premise"},{"node":"favor-composition-over-inheritance","truth_value":"IN","reason":"premise"}]}}