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Java Java Objects Harnessing the Power of Objects Handling Exceptions

Yu Ito
Yu Ito
12,711 Points
Posted by Yu Ito
Yu Ito
12,711 Points

I'm stuck on this task. Please help.

I have no idea how to code.

Example.java 
class Example {

  public static void main(String[] args) {
    GoKart kart = new GoKart("purple");
    if (kart.isBatteryEmpty()) {
      System.out.println("The battery is empty");
    }
    kart.drive(42);
  }
  catch (IllegalArgumentException iae) {
    System.out.printLn ("");
    System.out.printf ("", iae.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

codebyamir
codebyamir
12,108 Points

Hi Yu,

The challenge is asking you to handle the exception thrown when the number of laps passed to the drive method is greater than the bars remaining.

So if we look at the drive method, we can see it throws an exception of type IllegalArgumentException.

We can go back to Example.java and wrap the call to the drive method with a try-catch clause like below:

class Example {

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

    try {
      kart.drive(42);
    } catch (IllegalArgumentException e) {
      System.out.println(e.getMessage()); 
    }
  }
}
Yu Ito
Yu Ito
12,711 Points
Yu Ito
Yu Ito
12,711 Points

That works!! Thank you very much for your help Amir-san.