Free Low-level design lessonsLow-level design · Stage 1 · Case studies · Step 3
Case study: elevator system
A state machine and a scheduling policy: how an elevator decides where to go next, and how requests are modelled. About 14 minutes.
Which two things should be modelled as swappable, separate from the elevator's state machine?
- AThe scheduling policy for the next stop, and the dispatch policy across elevators
- BThe colour of the buttons and the door speed
- CThe number of floors only
Show the answer
The scheduling policy for the next stop, and the dispatch policy across elevators. Both are strategies that will change.
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