code: public Property copy() throws IOException, URISyntaxException, ParseException {
          if (factory == null) {
              throw new UnsupportedOperationException("No factory specified");
          }
          // Deep copy parameter list..
          final ParameterList params = new ParameterList(getParameters(), false);
          return factory.createProperty(params, getValue());
      }
docs: Create a (deep) copy of this property.
  
  @return the copy of the property
  @throws IOException        where an error occurs reading property data
  @throws URISyntaxException where the property contains an invalid URI value
  @throws ParseException     where the property contains an invalid date value