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Java Java Objects Harnessing the Power of Objects Handling Exceptions

Protect the call to kart.drive by handling the IllegalArgumentException. Why there is a compile err?

The code looks exactly as in a lesson.

Example.java
class Example {

  public static void main(String[] args) {
    GoKart kart = new GoKart("purple");
    if (kart.isBatteryEmpty()) {
      System.out.println("The battery is empty");
                               }
    try {
      kart.drive(42);
      }

    catch (IllegalArgumentException iae) {
      System.out.println("Not enough power %s", iae.getMessage());
      }
    }

}
GoKart.java
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() {
    drive(1);
  }

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

}

2 Answers

Hi Andrei,

If you want to do in-place substitution you should use printf instead of println in your catch block.

I got it. Just before loosing all my patience :) Thank you, anyway!