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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Posted by Jahmal Blanchard
Jahmal Blanchard
5,054 Points

IllegalArgumentException practice

I'm trying to create logic for my drive method w/ parameters but I keep get an error. Its telling me to add IAE before I change my variables. I went through the tutorial and I get the example but struggling on this.

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) {
    lapsDriven += laps;
    int newBarCount = barCount -= laps;
    if (newBarCount < 0 ) {
         throw new IllegalArgumentException("No Gas");
    }


    barCount = newBarCount;
  }
}

2 Answers

Tim Betz
Tim Betz
15,146 Points
Tim Betz
Tim Betz
15,146 Points

I think the problem is, you need to throw the exception if the barCount reached zero, so use <= 0. Here is my code for reference.

  public void drive(int laps) {
    if (barCount <= 0) {
      throw new IllegalArgumentException("Error Message!");
    }
    lapsDriven += laps;
    barCount -= laps;
  }
Jahmal Blanchard
Jahmal Blanchard
5,054 Points
Jahmal Blanchard
Jahmal Blanchard
5,054 Points

Thank you!! I got it now.