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Java Java Objects (Retired) Harnessing the Power of Objects Method Signatures

Something seems to be wrong with my method

whats wrong with my method?

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

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

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

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


1 Answer


For this you need to create another method called drive that takes no parameters and makes the kart drive 1 lap. You can use the existing drive method for that second part.

public void drive() {

This can be called with drive() and will use the drive(int laps) method to just do one lap.

I hope that makes sense.