code: public BoxRequestsShare.AddCollaboration getAddToFileRequest(String fileId, BoxCollaboration.Role role, BoxCollaborator collaborator) {
          return new BoxRequestsShare.AddCollaboration(getCollaborationsUrl(),
                  BoxFile.createFromId(fileId), role, collaborator, mSession);
      }
docs: A request that adds a {@link com.box.androidsdk.content.models.BoxUser user} or {@link com.box.androidsdk.content.models.BoxGroup group} as a collaborator to a file.
  @param fileId id of the file to be collaborated.
  @param role role of the collaboration
  @param collaborator the {@link com.box.androidsdk.content.models.BoxUser user} or {@link com.box.androidsdk.content.models.BoxGroup group} to add as a collaborator
  @return request to add/create a collaboration