SAX.setDocumentLocator()
SAX.startDocument()
SAX.internalSubset(doc, , )
SAX.elementDecl(doc, 3, ...)
SAX.elementDecl(a, 3, ...)
SAX.elementDecl(b, 3, ...)
SAX.externalSubset(doc, , )
SAX.startElement(doc)
SAX.startElement(a)
SAX.characters(This, 4)
SAX.endElement(a)
SAX.characters( is a , 6)
SAX.startElement(b)
SAX.characters(valid, 5)
SAX.endElement(b)
SAX.characters( document, 9)
SAX.endElement(doc)
SAX.endDocument()