| 이름 | 설명 |
|---|---|
| SwitchGreen | SwitchGreen command switches the traffic light to green. |
| SwitchOrange | SwitchOrange command switches the traffic light to orange. |
| SwitchRed | SwitchRed command switches the traffic light to red. |
| Switcher | Switcher functions as a superclass for all our traffic light switcher classes and accepts a traffic light via dependency injection in the constructor. |