code: public Timestamp getTimestamp(String attributeName) {
          Object value = getRaw(attributeName);
          Converter<Object, Timestamp> converter = modelRegistryLocal.converterForValue(
                  attributeName, value, Timestamp.class);
          return converter != null ? converter.convert(value) : Convert.toTimestamp(value);
      }
docs: Gets attribute value as <code>java.sql.Timestamp</code>.
  If there is a {@link Converter} registered for the attribute that converts from Class <code>S</code> to Class
  <code>java.sql.Timestamp</code>, given the attribute value is an instance of <code>S</code>, then it will be
  used, otherwise performs a conversion using {@link Convert#toTimestamp(Object)}.
  
  @param attributeName name of attribute to convert
  @return instance of <code>Timestamp</code>