code: protected FileWrapper handleAddFileWithMultipartFile(Class<? extends FileEntity> type, Integer entityId, MultipartFile multipartFile,
                                                         String externalId, FileParams params, boolean deleteFile) {
  
          MultiValueMap<String, Object> multiValueMap = null;
          try {
              multiValueMap = restFileManager.addFileToMultiValueMap(multipartFile);
          } catch (IOException e) {
              log.error("Error creating temp file", e);
          }
          Map<String, String> uriVariables = restUriVariablesFactory.getUriVariablesForAddFile(BullhornEntityInfo.getTypesRestEntityName(type),
                  entityId, externalId, params);
          String url = restUrlFactory.assembleAddFileUrl(params);
  
          return this.handleAddFile(type, entityId, multiValueMap, url, uriVariables, multipartFile.getOriginalFilename(), deleteFile);
  
      }
docs: Makes the api call to add files to an entity. Takes a MultipartFile.
  
  @param type
  @param entityId
  @param multipartFile
  @param externalId
  @param params
  @param deleteFile
  @return