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

Why does this not work ?

It should work I dont understand

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 boolean charge() {
    mBarsCount = MAX_ENERGY_BARS;
    while (!isFullyCharged) {

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

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


1 Answer

Hey Lorcan,

Did you change the charge method to be a boolean method? You'll want to switch that back to return nothing (void). Secondly, you'll want to remove the current assignment of mBarsCount (It's assigned to MAX_ENERGY_BARS by default). Finally, don't forget your parentheses inside of your while condition when using isFullyCharged.

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