code: public static List<Annotation> getMetaDataDoc(String toplevelCorpusName,
      String documentName)
    {
      List<Annotation> result = new ArrayList<Annotation>();
      WebResource res = Helper.getAnnisWebResource();
      try
      {
        res = res.path("meta").path("doc")
          .path(urlPathEscape.escape(toplevelCorpusName));
        res = res.path(urlPathEscape.escape(documentName));
  
        result = res.get(new GenericType<List<Annotation>>()
        {
        });
      }
      catch (UniformInterfaceException | ClientHandlerException ex)
      {
        log.error(null, ex);
        if(!AnnisBaseUI.handleCommonError(ex, "retrieve metadata"))
        {
          Notification.show(
            "Remote exception: " + ex.getLocalizedMessage(),
            Notification.Type.WARNING_MESSAGE);
        }
      }
      return result;
    }
docs: Retrieve the meta data for a given document of a corpus.
  
  @param toplevelCorpusName specifies the toplevel corpus
  @param documentName specifies the document.
  @return returns only the meta data for a single document.