code: public void startPart(String contentType)
           throws IOException
      {
          if (inPart)
              out.write(__CRLF);
          inPart=true;
          out.write(__DASHDASH);
          out.write(boundaryBytes);
          out.write(__CRLF);
          out.write(("Content-Type: "+contentType).getBytes(StringUtil.__ISO_8859_1));
          out.write(__CRLF);
          out.write(__CRLF);
      }
docs: Start creation of the next Content.