MYSPOTFRAGMENT: ///////////////////////////////////////////////////////////////////////////

	View.OnClickListener leaveClickListener = view -> {
        user = SpotsManager.INSTANCE.getCurrentUser();

        try {
            DialogUtil.createOkNoThanksDialog(view.getContext(), getString(R.string.rate_spot),
                    new DialogUtil.InputDialogSubmitListenerForRating() {

                        @Override
                        public void onSubmit(int spotRating) {
                            user.addRating(parkingSpot.getId(), spotRating);

                            SpotsManager.INSTANCE.updateCurrentUser(user, new FirebaseEventResultListener() {
                                @Override
                                public void onSuccessful() {
                                    actionListener.onLeaveSpotButtonClicked();
                                }

                                @Override
                                public void onFailure(Exception e) {
                                    showMessage(Integer.parseInt(e.getMessage()));
                                }
                            });
                        }

                        @Override
                        public void onCancel() {
                            actionListener.onLeaveSpotButtonClicked();
                        }
                    }).show();
        } catch (NullPointerException e) {
            showMessage(R.string.default_errormessage);
            LogUtil.LogD(view.getContext(), R.string.default_errormessage);
        }
    };


USER: ///////////////////////////////////////////////////////////////////////////////

	private HashMap<String, Integer> ratings;

    public User() {
        this.ratings = new HashMap<>();
    }

    public User(String name, String email, String password, Boolean disabled) {
        this.name = name;
        this.email = email;
        this.password = password;
        this.disabled = disabled;
        this.ratings = new HashMap<>();
    }

    public HashMap<String, Integer> getRatings() {
        return ratings;
    }

    public User setRatings(HashMap<String, Integer> ratings) {
        this.ratings = ratings;
        return this;
    }

   public void addRating(String spotId, Integer ratingValue) {
        ratings.put(spotId, ratingValue);
    }