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Java Java Objects Harnessing the Power of Objects Overload Methods

Posted by Ryan White
Ryan White
8,160 Points

Modify the drive method to define a parameter of how many laps should be driven. Cant figure out what's wrong?

I've run into an issue trying to use short hand as seen below to modify laps driven. Help please.

GoKart.java 
class GoKart {
  public static final int MAX_BARS = 8;
  private String color;
  private int barCount;
  private int lapsDriven;
  private int laps;

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

1 Answer

Brennen Green
Brennen Green
923 Points

Hi, you made a very simple mistake, when using shorthand you need to add what will be added to the variable.

Here is an example of proper shorthand

  public void drive(int laps) {
    lapsDriven += laps; //Takes the lapsDriven variable and adds the parameter passed with the method to the value
    barCount -= laps; //Takes the barCount variable and subtracts the parameter passed with the method to the value
  }

Only when incrementing do you just write out the variable then the two operators

variable++; //Takes the value of the increment and increments it by one
variable--; //Takes the value of the variable and decrements it by one