code: @JsonIgnore
      @Override
      public Collection<Object> getValues() {
          List<Object> result = new ArrayList<Object>();
          groovyShell.setProperty("result", result);
          groovyShell.setProperty("extra", extra);
          groovyShell.evaluate(groovy);
          return result;
      }
docs: Runs the groovy and returns the values when serialized.
  {@inheritDoc}