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Java Java Objects (Retired) Harnessing the Power of Objects Incrementing

Charging the GoKart

Help how to solve this please.

Bummer! Use ++ to increment mBarsCount

By the way, is it just me or is the workspace console and objectives console really buggy?

public class GoKart {
  public static final int MAX_ENERGY_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;

  public String getColor() {
    return mColor;

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

  public boolean isFullyCharged() {
    return mBarsCount == MAX_ENERGY_BARS;

  public void charge(){
      mBarsCount ++;


1 Answer

Stone Preston
Stone Preston
42,016 Points

the postfix ++ operator conventionally goes directly after the name of the variable. you have a space between them

 public void charge(){

Thank you very much that works. Seems inconsistent though. Sometimes we can write

aVariable = 0 


aVariable ++
aVariable +=1

are not allowed.

Anyway thanks very much I will be more careful in future