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Java Java Objects Harnessing the Power of Objects Increment and Decrement

In your created drive method, increment the new lapsDriven variable by 1.

} private int lapsDriven; lapsDriven++; }

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

  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;
  }
  private int lapsDriven;
  lapsDriven++;
}

I don't know what to do to fix it. I tried a couple of times and I even restarted the challenge to see if it was my internet connection, but I'm still getting it wrong.

2 Answers

Hi Carla, you're almost there, there are a few things that you have missed though.

Not so much an error but it is considered good practice to put your variables at the top of your class

Problem

You set a private variable correctly and you also incremented correctly, all you need to do now is put that incrementation in a method.

I'll step through that below:

There are 4 parts to the structure of a basic method from left to right.

  1. Modifier
  2. Return type
  3. method name
  4. the value passed to the method (parameter)

The Challenge

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.

So we know from the description the modifier is public, it does not return anything and there are no values passed to the method.

public void drive() {

}

Solution

I hope this makes more sense now, Good Luck!

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() {
    this.lapsDriven++;
    this.barCount--;
  }
}

Thank you!