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Java Java Objects Harnessing the Power of Objects Overload Methods

Jack Cummins
Jack Cummins
17,417 Points

How can I do this?

The task is “Modify the drive method to define a parameter of how many laps should be driven. Update the method body to handle the new method”

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

1 Answer

Yanuar Prakoso
Yanuar Prakoso
15,196 Points

Hi Jack

Your current answer is enough to pass the first part of the challenge. However, to pass the second (final) part of the challenge you need to modify one of your drive method to apply for polymorphism a little bit deeper. The drive method which does not required you to pass anything must call the newly created drive method and pass an integer of 1:. This is how I will do:

public void drive() {
    /*you do not need these codes:
    lapsDriven++;
    barCount--;*/
    //you only need to call the newly created drive(int laps) method and pass an int = 1:
    drive(1);
  }
}
public void drive(int laps){
  lapsDriven += laps;
  barCount -=laps;
}

I hope this can help a little