code: public int getRecordSize() {
          if (this.tarIn != null) {
              return this.tarIn.getRecordSize();
          } else if (this.tarOut != null) {
              return this.tarOut.getRecordSize();
          }
  
          return TarBuffer.DEFAULT_RCDSIZE;
      }
docs: Get the archive's record size. Because of its history, tar supports the concept of buffered IO consisting of
  BLOCKS of RECORDS. This allowed tar to match the IO characteristics of the physical device being used. Of course,
  in the Java world, this makes no sense, WITH ONE EXCEPTION - archives are expected to be propertly "blocked".
  Thus, all of the horrible TarBuffer support boils down to simply getting the "boundaries" correct.
  
  @return The record size this archive is using.