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Java Java Objects Harnessing the Power of Objects Handling Exceptions

why does this not work

public class Example { public static void main(String[] args) { GoKart kart = new GoKart("yellow"); if (kart.isBatteryEmpty()) { System.out.println("The battery is empty"); } try { kart.drive(2); }

  catch (IllegalArgumentException e) {
    System.out.println(e.getMessage());
  }
}

}

Example.java
public class Example {
    public static void main(String[] args) {
        GoKart kart = new GoKart("yellow");
        if (kart.isBatteryEmpty()) {
          System.out.println("The battery is empty");
        }
      try { 
        kart.drive(2);

      } 

      catch (IllegalArgumentException e) {
        System.out.println(e.getMessage());
      }
    }
}
GoKart.java
class GoKart {
  public static final int MAX_BARS = 8;
  private int barCount;
  private String color;
  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 (laps > barCount) {
      throw new IllegalArgumentException("Not enough battery remains");
    }
    lapsDriven += laps;
    barCount -= laps;
  }

}

1 Answer

andren
andren
28,558 Points

It does not work because you (accidentally?) changed the value that gets passed to the drive method. When the challenge loads the argument supplied to it is 42, you have changed that to 2.

Changing any code you are not explicitly asked to change during a challenge will often lead to the code checker getting confused which will prevent you from completing the challenge.

If you simply change it back to 42 like this:

public class Example {
    public static void main(String[] args) {
        GoKart kart = new GoKart("yellow");
        if (kart.isBatteryEmpty()) {
          System.out.println("The battery is empty");
        }
      try { 
        kart.drive(42);

      } 

      catch (IllegalArgumentException e) {
        System.out.println(e.getMessage());
      }
    }
}

Then you will be able to pass the challenge as the rest of your code is fine.