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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Simon Feuster
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Simon Feuster
Full Stack JavaScript Techdegree Graduate 28,036 Points

IllegalArgumentException

Hi, can someone help me with this. I don't understand why the code isn't working. Thanks

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) {
    int newAmount = lapsDriven + laps;
    if(newAmount > MAX_BARS) {
     throw new IllegalArgumentException ("To many laps");
    }
    lapsDriven = newAmount;
    barCount -= laps;
  }
}

2 Answers

Hi Simon,

The error that the compiler reports with your code is Make sure you throw a new IllegalArgumentException if the requested amount of laps would make the battery less than zero.

The aim of the revised drive method is to make sure that the received parameter value, laps is not greater than the number of bars held in barCount. So, if laps is greater than barCount throw the exception, if not, add laps to lapsDriven and deduct laps from barCount.

Make sense?

Steve.

P.S. You don't need any new variables for this challenge.

No problem. Did you get it solved?

:+1: :smile: