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Java Java Objects Harnessing the Power of Objects Handling Exceptions

Enyang Mercy
PLUS
Enyang Mercy
Courses Plus Student 2,339 Points

Exception handling protect the call the method by handling iae print out the message

how do i protect the call to kart.drive by handling the iae thrown?

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);
      System.out.println("Not enough battery remains");
    } catch (IllegalArgumentException iae) {
      System.out.println("Oh no!");
      System.out.println("The error was %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;
  }

}

1 Answer

Hi Enyang,

You have 3 problems in your catch block:

  1. The letter m in getmessage() should be capitalised: getMessage()
  2. You are missing a semicolon after getMessage());
  3. If you want to do string substitution you should use printf instead of println