code: InputStream getInputStream() throws IOException {
          switch (filetype) {
              case GZ:
                  LOG.debug("Decompressing .gz file");
                  return new GzipCompressorInputStream(new FileInputStream(compressedFile));
              case BZ2:
                  LOG.debug("Decompressing .bz2 file");
                  return new BZip2CompressorInputStream(new FileInputStream(compressedFile));
          }
          return null;
      }
docs: Get an InputStream for the decompressed file.
  
  @return An InputStream, the type could be BZip2CompressorInputStream, or GzipCompressorInputStream depending on what type of file was initially supplied
  @throws IOException IOException