code: public String uploadFile(UploadFileRequest request) throws AbstractCosException {
  		request.check_param();
  
  		String localPath = request.getLocalPath();
  		long fileSize = 0;
  		try {
  			fileSize = CommonFileUtils.getFileLength(localPath);
  		} catch (Exception e) {
  			throw new UnknownException(e.toString());
  		}
  
  		long suitSingleFileSize = 8 * 1024 * 1024;
  		if (fileSize < suitSingleFileSize) {
  			return uploadSingleFile(request);
  		} else {
  			UploadSliceFileRequest sliceRequest = new UploadSliceFileRequest(request);
  			sliceRequest.setInsertOnly(request.getInsertOnly());
  			return uploadSliceFile(sliceRequest);
  		}
  	}
docs: 上传文件请求, 对小文件(8MB以下使用单文件上传接口）, 大文件使用分片上传接口
  
  @param request
  上传文件请求
  @return JSON格式的字符串, 格式为{"code":$code, "message":"$mess"}, code为0表示成功,
  其他为失败, message为success或者失败原因
  @throws AbstractCosException
  SDK定义的COS异常, 通常是输入参数有误或者环境问题(如网络不通)