Feat: Implement selection via buffer in database

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/database/DatabaseHandler.java

@@ -121,13 +121,22 @@ public class DatabaseHandler {
 
     public static List<? extends CityObject> getBufferIntersectingObjects(CityObject co, Double buffersize) {
         ResultSet rs = null;
+    public static List<CityObject> getBufferIntersectingObjects(CityObject co, Double buffersize) {
+        List<CityObject> intersectingObjects = new ArrayList<>();
         try (Connection con = new ConnectionWrapper(H2GISDBFactory.openSpatialDataBase(DB_NAME))) {
-
+            try (PreparedStatement ps = con.prepareStatement("SELECT gmlid, bbox, data, type FROM features AS tab1" +
+                    " WHERE ST_INTERSECTS(ST_BUFFER(tab1.geom,?), (SELECT GEOM FROM features WHERE gmlid = ?)) AND tab1.gmlid <> ?")) {
+                ps.setDouble(1, buffersize);
+                ps.setString(2, co.getGmlId().toString());
+                ps.setString(3, co.getGmlId().toString());
+                ResultSet rs = ps.executeQuery();
+                intersectingObjects.addAll(retrieveCityObjects(rs));
+            }
         } catch (SQLException e) {
             logger.error("Connection to database failed while trying to get buffer intersecting objects!");
             logger.debug(e.getMessage());
         }
-        return Collections.emptyList();
+        return intersectingObjects;
     }
 
     public static List<CityObject> getBBoxIntersectingObjects(CityObject co) {