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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Jessie Burton
Jessie Burton
5,198 Points
Posted by Jessie Burton
Jessie Burton
5,198 Points

Ive tried everything but the exact thing it wants but not specifing

Ive tried barCount < 0, etc still nothing

GoKart.java 
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() {
    drive(1);
  }

  public void drive(int laps) {
    if (barCount < 0) {
      throw new IllegalArgumentException();
    } 
    lapsDriven += laps;
    barCount -= laps;
  }
}

2 Answers

jailanihar
PLUS
jailanihar
Courses Plus Student 3,773 Points
jailanihar
jailanihar
Courses Plus Student 3,773 Points 
public void drive(int laps) {
  if (barCount < 0) {
    throw new IllegalArgumentException();
  } 
  lapsDriven += laps;
  barCount -= laps;
}

From what I understand from your code is that you don't want to have negative barCount before incrementing lapsDriven and decementing barCount. So if the laps is more than the barCount it should throw an Exception.

Currently when it drive, it just check if the barCount is less than 0. Eventhough the number of laps passed is more than the barCount (assuming the current barCount is still positive or zero), it will not throw an Exception. Then it will increment the lapsDriven with the number of laps and it is possible to decrement barCount to negative value.

My suggestion is to fix the if statement to check if the subtraction of barCount and laps is less than zero then throw an Exception.

I hope that helps.

Edit: Apologies, I am quite new to the community discussion. I just realise that the code is from a course challenge. I was assuming it was your own code. But the suggestion I gave should work.

travis dumont
travis dumont
4,898 Points
travis dumont
travis dumont
4,898 Points

HI there,

I just did the challenge on there. The challenge is asking you to throw the exception when the bars are less then or equal to 0 for a start. Also, you need to include an else case in your method. Hope this helps :).