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Java Java Objects (Retired) Harnessing the Power of Objects Throwing Exceptions

jatinder kumar
jatinder kumar
Courses Plus Student 4,886 Points

whats wrong with this code, its not getting passed

if(laps>mBarsCount) { throw new IllegalArgumentException("Not enough battery remains"); }

public class GoKart {
  public static final int MAX_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;

  public String getColor() {
    return mColor;

  public void drive() {

  public void drive(int laps) {
    // Other driving code omitted for clarity purposes
    mBarsCount -= laps;

      throw new IllegalArgumentException("Not enough battery remains");

  public void charge() {
    while (!isFullyCharged()) {

  public boolean isBatteryEmpty() {
    return mBarsCount == 0;

  public boolean isFullyCharged() {
    return mBarsCount == MAX_BARS;


1 Answer

Jennifer Nordell
Jennifer Nordell
Treehouse Teacher

Hi there! It's not so much that the code is wrong but rather that it's a little out of order. In fact, you're so close here I'm not even going to give the direct answer. I'm just going to tell you how the logic of that is working. Right now when the function executes the first thing it does is reduce the mBarsCount. It does this before it even checks if there's enough battery :smiley: Try putting that reduction to mBarsCount in the proper place. You've got this! :sparkles: