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Start your free trialJames Kane
Front End Web Development Techdegree Student 3,070 PointsHELP. Well past the 20 minute rule been at this for almost 90 minutes, can someone please tell me what im doing wrong :(
Any advice much appreciated
class GoKart {
public static final int MAX_BARS = 8;
private String color;
private int barCount;
private int lapsDriven;
public GoKart(String color) {
this.color = color;
}
public String getColor() {
return color;
}
public void charge() {
barCount = MAX_BARS;
}
public boolean isBatteryEmpty() {
return barCount == 0;
}
public boolean isFullyCharged() {
return MAX_BARS == barCount;
}
public void drive() {
drive(1);
}
public void drive(int laps) {
lapsDriven += laps;
barCount -= laps;
int fuelRemaining = barCount - lapsDriven;
if (fuelRemaining < laps) {
throw new IllegalArgumentException("Not enough fuel");
}
}
}
2 Answers
Steve Hunter
57,712 PointsHi James,
You're nearly there!
You wan't to check if the number of laps
being requested is greater than the value held in barCount
. if
it is, throw the exception, as you have done else
do the maths piece.
Your method is "doing the maths" irrespective, so it'll allow barCount
to become negative if laps
is greater than it. That's what we're trying to protect against.
So, test whether laps
is greater than barCount
and if
it is, throw
the IllegalArgumentException
- else
deduct laps
from barCount
and increase lapsDriven
by laps
.
That all looks something like:
public void drive(int laps) {
if(laps > barCount){
throw new IllegalArgumentException("Not enough bars!");
} else {
lapsDriven += laps;
barCount -= laps;
}
}
Make sense?
Steve.
Suleyman Orazgulyyev
Courses Plus Student 5,798 PointsHey! So basically you have to check if the number of laps inputted is greater than the number of batteries. If it is, it means that there is not enough battery so you throw an exception. Here it is:
public void drive(int laps) {
if(barCount >= laps){
lapsDriven += laps;
barCount -= laps;
}else{
throw new IllegalArgumentException("Error!");
}
}
Steve Hunter
57,712 PointsSteve Hunter
57,712 PointsYou can omit the
else
part as the method will exit if the exception is thrown so it'll not run if that's the case. But, personally, I prefer it being there for improved readability. The code below is fine but it doesn't highlight the binary nature of the code as either the exception will be thrown or the maths bit will happen; never both. I think the addition of theelse
clause makes that far more obvious.James Kane
Front End Web Development Techdegree Student 3,070 PointsJames Kane
Front End Web Development Techdegree Student 3,070 PointsYes Steve thanks a lot man!