In client-server object-oriented programs, every object performs operations on data. The data may come from 2 directions:
- from client code through method arguments
- from storage (or service representing storage)
Operation data must not come to the object as a dependency through the class constructor.
Only the dependency services that help perform operations on the data must be retrieved as constructor dependencies.
Client-server framework Request objects are application arguments. They contain operation data. They must not be requested as dependencies in constructors.