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

Benneth Paredis
Benneth Paredis
4,597 Points
Posted by Benneth Paredis
Benneth Paredis
4,597 Points

need help with the go kart excercise

It seems like im doing this excercise wrong but i dont know what im doing wrong can somebody please help me ?

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

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

    if ( mBarsCount < 0) {
      throw new IllegalArgumentException ("Not enough battery remains");
    }
     mBarsCount -= laps;
  }

  public void charge() {
    while (!isFullyCharged()) {
      mBarsCount++;
    }
  }

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

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

}

1 Answer

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Benneth,

your code syntax is fine, but the logic can be improved :)

So the only thing you need to change is replacing 0 with laps, because you are comparing mBarsCount with laps. If you want to drive more laps as the bars inside mBarsCount, the exception will be thrown.

 public void drive(int laps) {
    if (mBarsCount<laps) {
      throw new IllegalArgumentException ("Not enough battery remains");
    }
    mBarsCount -= laps;
  }

Does it make sense?

Grigorij

Benneth Paredis
Benneth Paredis
4,597 Points
Benneth Paredis
Benneth Paredis
4,597 Points

Thank you very much now it makes sense.