code: public void setPreviousElement(String element, String value) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, InstantiationException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException {
          Reflections reflections = new Reflections("com.stratio");
          Set classes = reflections.getSubTypesOf(CommonG.class);
  
          Object pp = (classes.toArray())[0];
          String qq = (pp.toString().split(" "))[1];
          Class<?> c = Class.forName(qq.toString());
  
          Field ff = c.getDeclaredField(element);
          ff.setAccessible(true);
          ff.set(null, value);
      }
docs: Saves the value in the attribute in class extending CommonG.
  
  @param element attribute in class where to store the value
  @param value   value to be stored
  @throws NoSuchFieldException      exception
  @throws SecurityException         exception
  @throws IllegalArgumentException  exception
  @throws IllegalAccessException    exception
  @throws InstantiationException    exception
  @throws ClassNotFoundException    exception
  @throws NoSuchMethodException     exception
  @throws InvocationTargetException exception