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

Posted by Mark John
Mark John
Courses Plus Student 771 Points

i got some problems with this java challenge question

okay, so lets throw an IllegalArgumentException from the drive method if the requested number of laps cannot be completed on the current battery level.make the exception massage "Not enough battery remains"..... plz every one i av been trying with this for a while now. i need help with it.

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

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

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

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

}

2 Answers

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

Hi Mark,

 public void drive(int laps) {
     if (laps > mBarsCount) {
     throw new IllegalArgumentException (" Not enough battery remains"); // word "remains" added
     } 
// mBarsCount = laps; code deleted (makes no sense :))
     mBarsCount -= laps;
// mBarsCount should be reduced if no exception is thrown
// the compiler checks the condition (laps > mBarsCount) first and if laps < mBarsCount the mBarsCount will be reduced
  }

Makes sense?

Grigorij

Mark John
PLUS
Mark John
Courses Plus Student 771 Points
Mark John
Mark John
Courses Plus Student 771 Points

thanks!! i did not take notice of that.. thanks!

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

Hey Mark,

glad I could help :)

Grigorij