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Java Java Objects (Retired) Harnessing the Power of Objects Throwing Exceptions

Aaron Williams
Aaron Williams
1,702 Points

I am not sure how to do this!

throw an IllegalArgumentException from the drive method if the requested number of laps cannot be completed on the current battery level. Make the exception message "Not enough battery remains".

public class GoKart {
  public static final int MAX_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;

  public String getColor() {
    return mColor;

  public void drive() {

  public void drive(int laps) {
    // Other driving code omitted for clarity purposes
    mBarsCount -= laps;

  public void charge() {
    while (!isFullyCharged()) {

  public boolean isBatteryEmpty() {
    return mBarsCount == 0;

  public boolean isFullyCharged() {
    return mBarsCount == MAX_BARS;


2 Answers

Lee Reynolds Jr.
Lee Reynolds Jr.
5,160 Points

Inside the drive method, you are supposed to add the exception for when the battery isn't enough. Try using an if statement that goes into an Exception throw. I hope this helps. Happy coding :)

  public void load(int pezAmount) {
    int newAmount = mPezCount + pezAmount;
    if (newAmount > MAX_PEZ) {
      throw new IllegalArgumentException("Too many pez!");

Follow the above example to modify the drive method that takes an argument (int laps).