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Java Java Objects Harnessing the Power of Objects Throwing Exceptions

Tafseer Khan
Tafseer Khan
1,107 Points

Unable to complete objective

Can someone tell me what is wrong with my code? it is not executing. This is the objective question: 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.

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 newCount=lapsDriven + laps;
    if(newCount>MAX_BARS){
      throw new IllegalArgumentException("TOO many laps");
    }

    barCount -= laps;
  }
}

I think you don't need newCount. You need to check if the laps the user wants to drive is greater than the current barCount.

2 Answers

Jethro Ocean
Jethro Ocean
2,458 Points

I think you just need to subtract the number of laps to the current barCount to check whether the barCount is enough for the number of laps inputted.

Tafseer Khan
Tafseer Khan
1,107 Points

I have updated my question with the actual question in the objective. the question specifically asks to use "throw".

Tafseer Khan
Tafseer Khan
1,107 Points

solved the problem. hope it helps others who find any difficulty in this challenge. here's the code- class GoKart { public static final int MAX_BARS = 8; private int barCount; private String color; 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 > barCount) { throw new IllegalArgumentException("Not enough battery remains"); } lapsDriven += laps; barCount -= laps; }

}