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

Java Objects Challenge

I need help. The editor says I have 1 error but I don't where.

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 wasCharged = false;

    if (!isFullyCharged()) {
      while (isFullyCharged()) {
      wasCharged = true;

2 Answers

Nicholas Kotsiantos
Nicholas Kotsiantos
8,827 Points

I believe you need a return statement in the isFullyCharged() method. Can you copy and paste what is in the preview tab?

You're going to have to rewrite the isFullyCharged method. Return the result of a boolean test in that method to see if the MAX_BARS_COUNT is equal to mBarsCount. I think I see what you're trying to do in the if loop in order to increment the charge, but that has to be in a separate method from the isFullyCharged method. Also, you might want to use a do/while loop for the incremental charging of the go-cart, there no if/while loop, I think.