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Java Java Objects Harnessing the Power of Objects Increment and Decrement

Caleb Austin
Caleb Austin
1,408 Points

Trouble in this objective

I am struggling with figuring out how to successfully approach this objective. Any help would be much appreciated. Thanks!

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 isFullyCharged() {
    return MAX_BARS == barCount;

  public void drive() {
    lapsDriven == 0;


1 Answer

John Anselmo
John Anselmo
Courses Plus Student 2,281 Points

I noticed you finished task 1/3 based on you already having your drive() method.

For task 2/3 : Great! Now let's write a simple drive method. It should be public and not return anything. We'll start out basic, calling the drive method will make the GoKart drive a single lap.

In your newly created drive method, increment the new lapsDriven variable by 1. Use the incrementing shorthand to increase lapsDriven.

What you want to do is take away the lapsDriven == 0; that you have in your drive() method because whenever you call drive() it resets the lapsDriven variable to 0, and you don't want that. So just having:

public void drive(){

is fine for task 2/3.

Now for task 3/3: Each lap around the track takes exactly 1 energy bar from the battery.

For this final task, in your drive method, decrement the battery's status that we maintain in the private field barCount.

Take your newly fixed code from task 2/3 and add barCount--; to the drive() method because the task wants you to subtract 1 from barCount whenever you complete a lap. So your drive method should now look like this:

public void drive(){

i'm following along here! My 1st task passes, then when i enter this data:

public void drive(){ lapsDriven++; }

it gives me a fail: "Oops! It looks like Task 1 is no longer passing."