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Java Java Objects Harnessing the Power of Objects Handling Exceptions

Mee Her
Mee Her
2,877 Points

IllegalArgumentException Help!!!

Hello. I am having trouble understanding the IllegalArgumentException method. I thought I understood it until I had to execute it in this problem and I keep getting the error

java.lang.IllegalArgumentException: Not enough battery remains! (Look around GoKart.java line 33)

I have the try and the catch but I can't seem to find out what I'm missing. I would appreciate the help if anyone has the slightest clue what I am doing wrong.

class Example {

  public static void main(String[] args) {
    GoKart kart = new GoKart("purple");
    if (kart.isBatteryEmpty()) {
      System.out.println("The battery is empty");
    try { 
  } catch (IllegalArgumentException iae) { 
    System.out.println("Not enough battery remains"); 
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() {

  public void drive(int laps) {
    if (laps > barCount) {
      throw new IllegalArgumentException("Not enough battery remains!");
    lapsDriven += laps;
    barCount -= laps;


1 Answer

Carlos Vallejo
Carlos Vallejo
11,821 Points

Hi Mee

Seem to be that is something missing in your drive method. You have to control that the number of laps. It can not be exceeded, for that is the MAX_BARS constant. See below my code and try again :).

public void drive(int laps) { int lapsAmount = lapsDriven + laps; if (lapsAmount > MAX_BARS){ throw new IllegalArgumentException("It was exceed the number of laps"); } lapsDriven = lapsAmount; barCount -= laps; }