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Java Java Objects (Retired) Harnessing the Power of Objects Method Signatures

Tuan Zen
Tuan Zen
6,882 Points

Pass in parameter of 1 after overload method?

I called the original method but i cant understand why/how to pass in that parameter 1. I thought mBarsCount-- would automatically subtract 1?

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(int laps) {
    // Other driving code omitted for clarity purposes
    mBarsCount -= laps;
  }

  public void drive() {
    mBarsCount--;
  }

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

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

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

}

2 Answers

Florian Tönjes
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Florian Tönjes
Full Stack JavaScript Techdegree Graduate 50,856 Points

Hey Tuan,

the challenge wants you to call the existing drive method that takes the int laps as a parameter.

    public void drive() {
        // Call the existing "drive(int laps)" method here and pass in the parameter for it to drive 1 lap.
    }

Try this:

  public void drive() {
    drive(1);
  }

Yes, the code "mBarsCount--" would automatically substract and therefor work, but the goal of this exercise is to learn to reuse function/methods instead of implementing similiar logic in different places (makes for example later refactoring easier, ...)