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Java Java Objects Harnessing the Power of Objects Handling Exceptions

Throwing excepctions in java

Ok, im a little stuck here. Im wrapping my drive method in a try block and I think I have the syntax right (it compiles in my local IDE). Can anybody spot the mistake?

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.printf("There is not enough charge in the battery to go that many laps: ", iae.getMessage() ); 

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

28,538 Points

You have forgotten to place a %s placeholder inside of the string you print out. Which means that you don't actually print out the message you get from the exception.

If you add the %s placeholder like this:

System.out.printf("There is not enough charge in the battery to go that many laps: %s", iae.getMessage() ); 

Then your solution will be accepted.

Yep, that's what it was. Thanks bunches!