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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Can someone please help me figure out what's wrong?

This is what I have to do: You probably already spotted the error in the drive method that accepts laps. You can drive way more laps than our battery can handle. Let's fix it.

Add logic to the drive method so that it throws an IllegalArgumentException if there aren't enough bars to support the laps request. Remember it takes 1 bar of energy to go around a lap.

Please try to help me out with this! I await anyone's response!

My code so far:

class GoKart { public static final int MAX_BARS = 8; private String color; private int barCount; 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) { int totalLaps = lapsDriven += laps; if (totalLaps > MAX_BARS) { throw new IllegalArgumentException("You cannot drive this much!"); } barCount = laps; } }

GoKart.java
class GoKart {
  public static final int MAX_BARS = 8;
  private String color;
  private int barCount;
  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) {
    int totalLaps = lapsDriven += laps;
    if (totalLaps > MAX_BARS) {
      throw new IllegalArgumentException("You cannot drive this much!");
    }
    barCount = laps;
  }
}

2 Answers

Tonnie Fanadez
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.a{fill-rule:evenodd;}techdegree seal-36
Tonnie Fanadez
UX Design Techdegree Graduate 22,796 Points

Hello Tianerad 999

Thanks for sharing your code.

All you need to do is to make sure the ride is not available when there is less than 1 bar count using if-statement then throw the Exception.

Please see how I did it on the below code snippet inside drive() method.

public void drive(int laps) {
    lapsDriven += laps;

    if (barCount<1){
    throw new IllegalArgumentException("You cannot drive this much!");
    }
    barCount -= laps;
  }

Cheers Man, keep going..

Oh! Ok, thanks for making things clearer!