public Object callSensorMethod(String methodname) {
   if (methodname.lastIndexOf('.') == -1) {
     Log.d("SeattleSensor", "Invalid XMLRPC method call");
     return null;
   }
   String classname = methodname.substring(0, methodname.lastIndexOf('.'));
   methodname = methodname.substring(methodname.lastIndexOf('.') + 1);
   SensorValue val = invokeMethod(classname, methodname);
   if (val != null) {
     AbstractSensor sensor = getSensorWithName(classname);
     return Privacy.anonymize(val, sensor.getPrivacylevel()).getValue();
   }
   return null;
 }