code: @Deprecated
      public String getContentType() {
          if (extraElements != null && extraElements.containsKey("contentType")) {
              return extraElements.getString("contentType");
          } else {
              throw new MongoGridFSException("No contentType data for this GridFS file");
          }
      }
docs: The content type of the file
  
  @return the content type of the file
  @deprecated content type information should be stored the metadata document instead.