I would use an enum with a value for the multiplier like this.
Code:
public enum ExperienceMode {
EASY(100),
MEDIUM(50),
HARD(25),
EXTREME(5);
private int multiplier;
public ExperienceMode(int multiplier) {
this.multiplier = multiplier;
}
private int getMultiplier() {
return this.multiplier;
}
}
You would add a variable in the client class with getter and setter methods to obtain the correct ExperienceMode. In your addExperience method apply the multplier.
Code:
int amount = c.getExperienceMode().getMultiplier();
Applying the multiplier might be a little different, just make the math make sense. I did this in quick reply but it should be pretty easy to set up. If you don't understand i can elaborate, just post the appropriate methods.