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Java Java Objects Harnessing the Power of Objects Handling Exceptions

David King
David King
683 Points

I don't know how to solve this java objects question

please help me, thanks!

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);
  }

}
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

Mihai Craciun
Mihai Craciun
13,520 Points

The challenge ask you to protect the drive method in a try..catch block. If you look in the method drive from the GoKart object it throw an IllegalArgumentException inside the method. So when you appeal the method from the Main class it has to be protected. In the end the main should look like this:

  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 iae){
     System.out.println(iae.getMessage()); 
    }
  }