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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Amir Tamim
Amir Tamim
8,597 Points
Posted by Amir Tamim
Amir Tamim
8,597 Points

Truly at a loss on this one:

Could someone guide me and point in the right direction?

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.

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) {

    if (laps>8){
      throw new IllegalArgumentException(); 
     }

    }
    lapsDriven += laps;
    barCount -= laps;
  }
}

2 Answers

Timothy Hilley
Timothy Hilley
2,292 Points
Timothy Hilley
Timothy Hilley
2,292 Points

lets look at it in a //psuedo code 

public void drive(int laps) {                             //the method is taking in the amount of desired laps to drive
if(laps > barCount) {                                        //since it takes one bar of fuel to do one lap, if theres not enough fuel
   throw new IllegalArgumentException();      //say WOAH thats too much to ask for. I'm only at half a tank.
}
lapsDriven += laps;                                           //if you have enough fuel, drive the laps
barCount -= laps;                                             //the laps used up fuel
}

you also have one too many } in there between your ifthrow and the rest of the content of the method This is my first try at helping so let me know if that works lol.

Pablo Villegas
Pablo Villegas
2,922 Points
Pablo Villegas
Pablo Villegas
2,922 Points

The problem lies in your conditional laps > 8. Think about what would happen if barCount is 2 after driving some laps. Would you condition laps > 8 work?