### Question:
GeoJsonFeature extends Feature implements Observer { public void setGeometry(Geometry geometry) { super.setGeometry(geometry); setChanged(); notifyObservers(); } GeoJsonFeature(Geometry geometry, String id,
                          HashMap<String, String> properties, LatLngBounds boundingBox); String setProperty(String property, String propertyValue); String removeProperty(String property); GeoJsonPointStyle getPointStyle(); void setPointStyle(GeoJsonPointStyle pointStyle); GeoJsonLineStringStyle getLineStringStyle(); void setLineStringStyle(GeoJsonLineStringStyle lineStringStyle); GeoJsonPolygonStyle getPolygonStyle(); void setPolygonStyle(GeoJsonPolygonStyle polygonStyle); PolygonOptions getPolygonOptions(); MarkerOptions getMarkerOptions(); PolylineOptions getPolylineOptions(); void setGeometry(Geometry geometry); LatLngBounds getBoundingBox(); @Override String toString(); @Override void update(Observable observable, Object data);  }### Answer:
@Test public void testGeometry() { GeoJsonFeature feature = new GeoJsonFeature(null, null, null, null); assertNull(feature.getGeometry()); GeoJsonPoint point = new GeoJsonPoint(new LatLng(0, 0)); feature.setGeometry(point); assertEquals(point, feature.getGeometry()); feature.setGeometry(null); assertNull(feature.getGeometry()); GeoJsonLineString lineString = new GeoJsonLineString( new ArrayList<>(Arrays.asList(new LatLng(0, 0), new LatLng(50, 50)))); feature = new GeoJsonFeature(lineString, null, null, null); assertEquals(lineString, feature.getGeometry()); feature.setGeometry(point); assertEquals(point, feature.getGeometry()); feature.setGeometry(null); assertNull(feature.getGeometry()); feature.setGeometry(lineString); assertEquals(lineString, feature.getGeometry()); }