docs: public boolean skipPreamble () throws IOException
    {
      // First delimiter may be not preceeded with a CRLF.
      System.arraycopy (m_aBoundary, 2, m_aBoundary, 0, m_aBoundary.length - 2);
      m_nBoundaryLength = m_aBoundary.length - 2;
      try
      {
        // Discard all data up to the delimiter.
        discardBodyData ();
  
        // Read boundary - if succeded, the stream contains an
        // encapsulation.
        return readBoundary ();
      }
      catch (final MultipartMalformedStreamException e)
      {
        return false;
      }
      finally
      {
        // Restore delimiter.
        System.arraycopy (m_aBoundary, 0, m_aBoundary, 2, m_aBoundary.length - 2);
        m_nBoundaryLength = m_aBoundary.length;
        m_aBoundary[0] = CR;
        m_aBoundary[1] = LF;
      }
    }