Illegal argument exception

Question

how to code throwing IllegalArgumentException "Not enough battery remains"

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
    mBarsCount -= laps;
  }

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

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

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

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

}

Answer 1 · 2016-07-11T05:38:21Z

July 11, 2016 5:38am

You're definitely on the right track here. In fact, it look likes there are just a few simple errors related to following the directions more closely and thinking about what you're trying to accomplish - the main exception throwing code looks good!

Checkout my hints for the drive(int lapsNumber) method:

public void drive(int lapsNumber) {
    if (lapsNumber < MAX_BARS) {        // the goal here is to check if we're trying to drive *more* laps than battery
      throw new IllegalArgumentException ("Not enough battery remains");     // check directions: the message needs punctuation, right?
    }
    mBarsCount = lapsNumber;  // this should decrease the bars by the number of laps (leave it as it originally was "-=")
  }

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Aldrich Alviar

Aldrich Alviar

Illegal argument exception

1 Answer

J.D. Sandifer

J.D. Sandifer