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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Please help what wrong with my exception

I dont unterstand why it doesnt work

if lapsDriven bigger than the barCount then we cant drive anymore. Thats what my code does or not

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() {


  public void drive(int laps) {
    lapsDriven += laps;
    barCount -= laps;

    if(lapsDriven > barCount){
    throw new IllegalArgumentException(" Your Batterie is to low to continue");

2 Answers

Michelle Bramlett
Michelle Bramlett
1,253 Points

Hello Nikolai,

I'm new at responding so hope I can help!

When I worked this challenge, this is how I laid out the last portion

public void drive(int laps) { if (laps > barsCount) { throw new IllegalArgumentException("Not enough battery remains"); } barsCount -= laps; }

Hope this helps!


Craig Dennis
Craig Dennis
Treehouse Teacher

You don't want to change things before you check do you? Then you'll get things in a weird state.

Let me know if that hint did it for ya.