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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Anders Pedersen
Anders Pedersen
734 Points
Posted by Anders Pedersen
Anders Pedersen
734 Points

I need help solving this.

Add logic to the drive methid so that it throws an IllegalArgumentException if there aren't enough bars to support the laps request. Remeber it takes 1 bar of energy to go around a lap.

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;
    barCount -= laps;
}

1 Answer

P J
P J
1,568 Points
P J
P J
1,568 Points

Hi Anders,

You want to throw an IllegalArgumentException if there aren't enough bars to support the laps. This means that if the battery doesn't have the right barCount you will need to throw the exception.

public void drive(int laps) {
    lapsDriven += laps;
    barCount -= laps;
}

is the method that you will need to change.

Again, you are trying to determine if the barCount is enough to handle the proposed laps

public void drive(int laps) {
    if (laps > barCount) {
    throw new IllegalArgumentException("Too many laps!");
 }
    lapsDriven += laps;
    barCount -= laps;
}