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Java Java Objects Harnessing the Power of Objects Handling Exceptions

William Smith
William Smith
3,840 Points

help, I'm not really sure what to do next.

Protect the call to kart.drive by handling the IllegalArgumentException that is thrown when not enough battery remains. Print out the message from the exception to the screen as you catch the exception.

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");
    }
    kart.drive(42);
  }

}
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

Seth Kroger
Seth Kroger
56,406 Points

Even if fully charged the battery won't have the capacity to drive 42 laps, so that line in Example.java will definitely cause an error. You're asked to catch it by surrounding it with a try/catch block.