code: public static Object[] getEncoding(JspInputSource inputSource)
          throws IOException, JspCoreException
      {
      	InputStream inStream = XMLEncodingDetector.getInputStream(inputSource);
      	//InputStream inStream = JspUtil.getInputStream(fname, jarFile, ctxt,
          //                                              err);
          XMLEncodingDetector detector = new XMLEncodingDetector();
          Object[] ret = detector.getEncoding(inStream);
          inStream.close();
  
          return ret;
      }
docs: Autodetects the encoding of the XML document supplied by the given
  input stream.
  
  Encoding autodetection is done according to the XML 1.0 specification,
  Appendix F.1: Detection Without External Encoding Information.
  
  @return Two-element array, where the first element (of type
  java.lang.String) contains the name of the (auto)detected encoding, and
  the second element (of type java.lang.Boolean) specifies whether the
  encoding was specified using the 'encoding' attribute of an XML prolog
  (TRUE) or autodetected (FALSE).