public ObjectProperty<NumberFormat> numberFormatProperty() {
        if (null == numberFormat) {
            numberFormat  = new ObjectPropertyBase<NumberFormat>(_numberFormat) {
                @Override protected void invalidated() {
                    if (null == get()) set(NumberFormat.getInstance(getLocale()));
                    fireTileEvent(RESIZE_EVENT);
                }
                @Override public Object getBean() { return Tile.this; }
                @Override public String getName() { return "numberFormat"; }
            };
            _numberFormat = null;
        }
        return numberFormat;
    }
Defines the number format that will be used to format the value
in the tile (NOT USED AT THE MOMENT)

@param FORMAT
src/main/java/eu/hansolo/tilesfx/Tile.java