code: @Override
      public int getId() {
          if (mId != 0) {
              return mId;
          }
  
          if (!TextUtils.isEmpty(mPath) && !TextUtils.isEmpty(mUrl)) {
              return mId = FileDownloadUtils.generateId(mUrl, mPath, mPathAsDirectory);
          }
  
          return 0;
      }
docs: ------------------- Get -----------------------