Question

public class GameManager {
    private static GameManager INSTANCE;

    private final int INITIAL_SCORE = 0;

    private int mCurrentScore;

    GameManager(){
    }

    public static GameManager getInstance(){
        if(INSTANCE == null){
            INSTANCE = new GameManager();
        }
        return INSTANCE;
    }

    public int getCurrentScore(){
        return mCurrentScore;
    }

    public void incrementScore(int pIncrementBy){
        mCurrentScore += pIncrementBy;
    }

    public void resetGame(){
        mCurrentScore = GameManager.INITIAL_SCORE;
    }
}

I run the above code in eclipse.
I’d like to know why eclipse told me “Cannot make a static reference to the non-static field GameManager.INITIAL_SCORE” when assigning the value of GameManager.INITIAL_SCORE to that of mCurrentScore. mCurrentScore is not static, is it? If mCurrentScore is not static, why should I declare INITIAL_SCORE as static?

Answer 1

When you prefix a variable with a class name you are telling Java the variable is static. Since the variable is not static it is giving you an error. The code should read:

public void resetGame(){
    mCurrentScore = INITIAL_SCORE;
}