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Java Java Objects (Retired) Harnessing the Power of Objects Incrementing

Elijah Parkhurst
Elijah Parkhurst
4,776 Points

I keep getting Bummer "Use ++ to increment the mBarsCount member field" when I am using ++ to increment.

I keep failing on this challenge. To the best of my knowledge I am close. For this challenge I didn't touch the method isFullyCharged but only changed the charge method. Do I need to do more or is there some kind of syntax problem that I am over looking?

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

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

  public String getColor() {
    return mColor;

  public void charge() {
    while (!isFullyCharged()) {
    mBarsCount ++;


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

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

Elijah Parkhurst
Elijah Parkhurst
4,776 Points

So I redid this challenge after posting this question and it passed!! I didn't type anything vastly different. I think the problem may have been in the space between mBarsCount and ++ but I'm not certain

1 Answer

Rob Bridges
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points

Hey Elijah,

Your code is great, there's just one small error, when incrementing try


No space between, when I copied your code in and tried to run it this fixed the problem, looks like a small error.

Thanks, let me know if this doesn't help.