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Java Java Objects Harnessing the Power of Objects Increment and Decrement

Megan Worswick
Megan Worswick
Courses Plus Student 359 Points

Increase lapsDriven by 1?

Hello, i'm trying to understand how to increase my laps by 1 for this question. can anyone explain where i'm going wrong?

class GoKart {
  public static final int MAX_BARS = 8;
  private String color;
  private int barCount;
  private int lapsDriven; 

  public GoKart(String color) {
    this.color = color;

  public String getColor() {
    return color;

  public void charge() {
    barCount = MAX_BARS;

  public boolean isBatteryEmpty() {
    return barCount == 0;
  public boolean Drive(){
    boolean lapsDriven = true;
    if (lapsDriven)){
      lapsDriven = LapsDriven + 1;

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

1 Answer

Ronald Williams
.a{fill-rule:evenodd;}techdegree seal-36
Ronald Williams
Java Web Development Techdegree Graduate 25,021 Points

Think of your drive method as what do you want to happen when the go kart is told to drive?

You probably want the laps to go up and the battery level to go down. If this is the case you could simply say:

public void drive() {

This says when drive is called on a go kart, add one to lapsDriven and take one away from barCount.

You make the method void because you are not looking for the method to RETURN something (for example: getColor which would return to you the color of the go kart as a String) you are looking for the method to just DO something, like decrease the go karts battery and increase the lap count.