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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

shu Chan
shu Chan
2,951 Points

Stuck on this challenge says " Make sure you throw the exception before you change the barCount and lapsDriven fields."

What am I doing wrong here?

GoKart.java
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 totalLaps = lapsDriven += laps; 
    barCount -= totalLaps; 
    if (totalLaps > MAX_BARS) {
    throw new IllegalArgumentException("Not enough Energy!!!"); }
    if (barCount < 0) {
    throw new IllegalArgumentException("Not enough Energy!!!"); }
    totalLaps = totalLaps;
  }
}

1 Answer

Hi there,

Yes, the purpose of throwing the error is to stop the user calling for more laps than bars. If this request happens, the kart should not drive, but the error should be thrown.

So, test if the value held by barCount is less than the number of requested laps. If it is, throw the exception else deduct laps from barCount. Also, add laps to lapsDriven

I hope that helps,

Steve.