code: protected <OBJ> OBJ filterIfSimpleText(OBJ value, FormMappingOption option, String propertyName, Class<?> propertyType) {
          if (value == null) {
              return null;
          }
          if (value instanceof String) {
              final String str = (String) value;
              if (option.getSimpleTextParameterFilter().isPresent()) { // basically false
                  // not use map() to avoid many new instances at main route (not here)
                  final FormSimpleTextParameterFilter filter = option.getSimpleTextParameterFilter().get();
                  final FormSimpleTextParameterMeta meta = createFormSimpleTextParameterMeta(propertyName, propertyType);
                  @SuppressWarnings("unchecked")
                  final OBJ filtered = (OBJ) filter.filter(str, meta);
                  return filtered;
              } else { // mainly here
                  return value;
              }
          } else if (value instanceof String[]) {
              final String[] ary = (String[]) value;
              option.getSimpleTextParameterFilter().ifPresent(filter -> {
                  final FormSimpleTextParameterMeta meta = createFormSimpleTextParameterMeta(propertyName, propertyType);
                  int index = 0;
                  for (String element : ary) {
                      if (element != null) { // just in case
                          ary[index] = filter.filter(element, meta);
                      }
                      ++index;
                  }
              });
              @SuppressWarnings("unchecked")
              final OBJ resultObj = (OBJ) ary;
              return resultObj;
          } else {
              return value;
          }
      }
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