Examination of the statechart diagram for the microwave oven reveals that the model fails to answer certain important questions:
What happens if we press the button when cooking is complete?
What happens if we press the button while cooking?
What happens if we press the button when the door is open?
Can we close the door when the door is already closed? (Put another way: What happens if we detect the doorClosed event when the door is already closed?)
The statechart diagram shows a set of states, events, and transitions, but the diagram cannot cover all possible combinations. In this section, we'll use an alternative representation of a state machine—the state transition table (STT)—to ensure completeness of the underlying ...