Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Kendhall Lebron Ruiz
Kendhall Lebron Ruiz
Pro Student 1,143 Points

I am stuck with the drive method

"Modify the drive method to define a parameter of how many laps should be driven. Update the method body to handle the new parameter." I've been stuck on this question for like 20 minutes and don't know what to do.
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() {

  public void drive(int laps) {
    lapsDriven += laps;
    barCount = laps-- ;
    if(barCount < 0){
    throw new IllegalArgumentException("Not enough batteries");

1 Answer

adrian miranda
adrian miranda
13,191 Points

First off, don't you want to check and throw the exception before you change anything? Move the check to the beginning.

Also, examine how you modify barCount closely. Don't you want to subtract from barCount?