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

Challenge Task - Harnessing the Power of Objects

I am honestly stuck on this task, am I being silly or blind?

I've used both the "!" and "while" but still get back "Bummer! Try again!" when I check my work.

Its frustrating at times but I do want to figure out what I am not doing correctly.

Thanks guys.

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() {
    mBarsCount = MAX_ENERGY_BARS;

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

  public boolean isFullyCharged() {
    boolean isMaxCharge = false;
    while (!isFullyCharged()) {
      isMaxCharge = true; 
    return mBarsCount == MAX_ENERGY_BARS;


1 Answer

Dan Johnson
Dan Johnson
40,532 Points

The charge method is what needs to be modified in order to make use of the isFullyCharged method:

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

Calling isFullyCharged from itself as you have posted will result in infinite recursion, as it has no edge case to terminate. No modification to isFullyCharged is needed for this challenge.

Ah! I understand now.

Thank you very much, this was bugging me for hours. Much appreciated Dan.