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David Dooley
3,028 PointsDon't understand the question.
Add logic to the drive method so that it throws an IllegalArgumentException if there aren't enough bars to support the laps request. Remember it takes 1 bar of energy to go around a lap.
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) {
int newAmount = laps;
if(newAmount < ){
throw new IllegalArgumentException("Too many bars");
}
lapsDriven+=laps;
barCount-=laps;
}
}
2 Answers

andren
28,538 PointsYou have to compare the amount of laps that is requested against the current battery bar count which is stored in the barCount
variable. Your current code is not too far of from correct, though I'd like to point out that the newAmount
variable you have created is entirely pointless as it is just a copy of the laps
variable that already exists within the method.
So to summarize compare barCount
against laps
. If the requested amount of laps is higher than the bars stored in the battery (barCount
) then you should throw the exception.

David Dooley
3,028 Pointsperfect gotcha thanks