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

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Posted by Grigorij Schleifer
Grigorij Schleifer
10,365 Points

non-static method cannot be referenced from a static context

i dont understand this :(

Can someone help me ... ?

GoKart.java 
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;

    while (mBarsCount != MAX_ENERGY_BARS) {
      GoKart.charge();
    } 
  }

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

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

}

2 Answers

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

This line seems to be the problem.

GoKart.charge();

Can you try incrementing mBarsCount in that while loop?

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Thanks Craig !

I have done it by my own:

public void charge() { mBarsCount = MAX_ENERGY_BARS;

 while (mBarsCount != MAX_ENERGY_BARS) {
       mBarsCount++ ;

                if ( mBarsCount == MAX_ENERGY_BARS) {
                            isFullyCharged();
                   } 
           }

}

But i dont understand the whole static vs non-static consept ;(