code: @Override
      public void close() throws IOException {
          try {
              if (inPart)
                  out.write(__CRLF);
              out.write(__DASHDASH);
              out.write(boundary);
              out.write(__DASHDASH);
              out.write(__CRLF);
              inPart = false;
          } finally {
              super.close();
          }
      }
docs: End the current part.
  
  @throws IOException IOException