### Question:
GeoJsonLineString extends LineString { public List<LatLng> getCoordinates() { return getGeometryObject(); } GeoJsonLineString(List<LatLng> coordinates);  GeoJsonLineString(List<LatLng> coordinates, List<Double> altitudes); String getType(); List<LatLng> getCoordinates(); List<Double> getAltitudes();  }### Answer:
@Test public void testGetCoordinates() { List<LatLng> coordinates = new ArrayList<>(); coordinates.add(new LatLng(0, 0)); coordinates.add(new LatLng(50, 50)); coordinates.add(new LatLng(100, 100)); ls = new GeoJsonLineString(coordinates); assertEquals(coordinates, ls.getCoordinates()); try { ls = new GeoJsonLineString(null); fail(); } catch (IllegalArgumentException e) { assertEquals("Coordinates cannot be null", e.getMessage()); } }