public ObjectProperty<LocalTime> durationProperty() {
        if (null == duration) {
            duration = new ObjectPropertyBase<LocalTime>(_duration) {
                @Override public Object getBean() { return Tile.this; }
                @Override public String getName() { return "duration"; }
            };
            _duration = null;
        }
        return duration;
    }
Defines a duration that is used in the TimeTileSkin
@param DURATION
src/main/java/eu/hansolo/tilesfx/Tile.java