code: public InputStream find(String id, String rev) {
          assertNotEmpty(id, "id");
          assertNotEmpty(rev, "rev");
          final URI uri = new DatabaseURIHelper(dbUri).documentUri(id, "rev", rev);
          return couchDbClient.get(uri);
      }
docs: Finds a document given id and revision and returns the result as {@link InputStream}.
  <p><b>Note</b>: The stream must be closed after use to release the connection.
  
  @param id  The document _id field.
  @param rev The document _rev field.
  @return The result as {@link InputStream}
  @throws NoDocumentException If the document is not found in the database.