Code Review Time!

Here is the logic for Warmer:

public class Warmer {
  private PotSensor myPotSensor;
  private Heater myHeater;
  public Warmer() { ... }
  public void trigger() {
    if (myPotSensor.isCoffeePresent()) {
      myHeater.on();
    }
    else {
      myHeater.off();
    }
  }
}