@Override
    public void startElement(String uri, String localName, String qName,
            Attributes atts) throws SAXException {

        if ("http://www.w3.org/1999/xhtml" != uri) {
            return;
        }

        int len = atts.getLength();
        for (int i = 0; i < len; i++) {
            String att = atts.getLocalName(i);
            if ("datatype" == att || "about" == att || "inlist" == att
                    || "rev" == att) {
                warn("RDFa Core attribute \u201C" + att
                        + "\u201D is not allowed in HTML5 + RDFa 1.1 Lite documents."
                        + GUIDANCE);
            } else if ("content" == att && "meta" != localName) {
                warnNonRDFaLite(localName, att);
            } else if (("rel" == att) && "a" != localName && "area" != localName
                    && "link" != localName) {
                warnNonRDFaLite(localName, att);
            }
        }
    }
@see nu.validator.checker.Checker#startElement(java.lang.String,
     java.lang.String, java.lang.String, org.xml.sax.Attributes)
src/nu/validator/checker/RdfaLiteChecker.java