SAX.setDocumentLocator()
SAX.startDocument()
SAX.internalSubset(doc, (null), (null))
SAX.elementDecl(doc, 4, ...)
SAX.elementDecl(a, 3, ...)
SAX.elementDecl(b, 3, ...)
SAX.startElement(doc)
SAX.startElement(a)
SAX.characters(This</a><b> is a valid</b><a> , 4)
SAX.endElement(a)
SAX.startElement(b)
SAX.characters( is a valid</b><a> document</a, 11)
SAX.endElement(b)
SAX.startElement(a)
SAX.characters( document</a></doc>
, 9)
SAX.endElement(a)
SAX.endElement(doc)
SAX.endDocument()