Not understanding why this throw exception isn't working?

Question

I just need help figuring out why this doesn't work and what I can do to, to make it work. When I run this I just get "Are you sure you threw the IllegalArgumentException if the requested amount of laps would make the battery less than zero?"

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(10);
  }

  public void drive(int laps) {
    // Other driving code omitted for clarity purposes
    //mBarsCount -= laps;
    int newAmount = mBarsCount + laps;
    if (newAmount > MAX_BARS) {
      throw new IllegalArgumentException("Not enough battery remains");
    }
    mBarsCount = newAmount;
  }

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

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

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

}

Answer 1 · 2016-02-02T01:40:23Z

February 2, 2016 1:40am

Hey Richard, your exception is fine you just need to clean the logic up to check and see if the number passed in for laps is higher is great than the current mBarsCount, next the only thing you need to do next is decrements the mBarsCount by the number of laps.

It would look something like below:

public void drive(int laps) {


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

Answer 2 · 2016-02-02T01:45:05Z

February 2, 2016 1:45am

Thank you so much, I understand why it needs to be done this way. Thanks again.

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Richard Groot

Richard Groot

Not understanding why this throw exception isn't working?

2 Answers

Rob Bridges

Rob Bridges

Richard Groot

Richard Groot