code: public Class getRootDeclarationClass() {
          ConfigPath res = this;
          while (res.getRoot() != null) {
              res = res.getRoot();
          }
          return res.getDeclarationClass();
      }
docs: Useful to filter out core dropwizard properties (where root type would be {@link io.dropwizard.Configuration}.
  
  @return root configuration class where entire path started