6 Matching Annotations
  1. Feb 2021
    1. I think a better, more immediately understandable name for this concept would be command object, because it lets you pass around commands (or a list of commands) as objects.

      That's the only thing you really need to know abut this pattern. The rest seems like boring implementation details that aren't that important, and that naturally follow from the primary definition above.

    1. In object-oriented programming, information hiding (by way of nesting of types) reduces software development risk by shifting the code's dependency on an uncertain implementation (design decision) onto a well-defined interface. Clients of the interface perform operations purely through it so if the implementation changes, the clients do not have to change.
  2. Oct 2020
  3. Feb 2019
  4. Jan 2019
    1. If one object is part of another object, then we use a diamond at the start of the arrow (next to the containing object), and a normal arrow at the end.

      Another way of thinking of this is, if the original owner (source) object and the owned (target) object share the same life cycle -- that is, the owned exists only when the owner does -- we say that the owner aggregates owned object(s). They share a whole-part relationship.

      What I did like very much about the video, was when the instructor pointed out that there's a small fallacy: aggregation, in OOD, does not really imply that owned object(s) must be a list.

  5. Sep 2015