code: protected String[] prepareStringArray(Object value, String propertyName, Class<?> proeprtyType, FormMappingOption option) { // not null (empty if null)
          final String[] result;
          if (value != null && value instanceof String[]) {
              result = (String[]) value;
          } else {
              result = value != null ? new String[] { value.toString() } : EMPTY_STRING_ARRAY;
          }
          return filterIfSimpleText(result, option, propertyName, proeprtyType);
      }
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