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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

I just can't understand the question.

where should I put IllegalArgumentException and how I will give condition to this.

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;

      throw new IllegalArgumentException();

1 Answer

Steven Parker
Steven Parker
229,920 Points

The challenge error message contains a clue: "Bummer: Make sure you throw the exception before you change the barCount and lapsDriven fields."

Right now, the code here is changing the fields, and then testing the result. But the instructions say to check first.

not working

Steven Parker
Steven Parker
229,920 Points

Clearly, you have to implement it a different way from above. If you're still having trouble after changing it, show what the new code looks like.