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

Shubham Modi
Shubham Modi
5,799 Points

I dont know what to do

Are you sure you threw the IllegalArgumentException if the requested amount of laps would make the battery less than zero?

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(MAX_BARS);
  }

  public void drive(int laps) {
    // Other driving code omitted for clarity purposes
     int newLaps = laps  - mBarsCount;
    if(newLaps < mBarsCount)
    {
      throw new IllegalArgumentException("Not Enough battery remains");
    }
    mBarsCount = newLaps;
    laps -=mBarsCount;
  }

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

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

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

}

1 Answer

Allan Clark
Allan Clark
10,810 Points

When we drive a number of laps we want to take the number of bars left and subtract the laps from it. It looks like you have the reverse operation, also subtracting again at the bottom. As a suggestion we can simplify your code by first comparing the number of laps we want to drive, if it is too many then we throw the exception, else do the subtraction. Something like this:

'''java

if(laps > mBarsCount) { //throw your exception }

mBarsCount -= laps;

'''