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

I totally do not understand what I need to do so may I please see the code for this question

java objects

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 void charge() {
    mBarsCount = MAX_ENERGY_BARS;

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

  public boolean isFullyCharged() {

    if (isBatteryEmpty())
    return mBarsCount == MAX_ENERGY_BARS;


1 Answer

The challenge is basically wanting us to make the charge() method a little more realistic; right now it goes from empty to charged instantly. They want us to use a while loop that checks to see if the isFullyCharged() method returns true if it doesn't then it will increment the mBarsCount variable until it does return true. This challenge is basically wanting us to be able to call a method within another method; if you are still feeling lost then here is the code:

public void charge() {
    //mBarsCount = MAX_ENERGY_BARS;  This isn't needed anymore so I commented it out.