Hi Adrian, There's lots you haven't said about what work you're actually measuring (e.g. what your SAX ContentHandler does) or how you're doing it (e.g. are you running warm-up iterations to let the JIT do its optimizations before starting to do your timing?), though I suspect at least a good chunk of what you're seeing is due to the cost of processing the 68 KB schema and not the actual validation time with it. You should take a look at the grammar caching capabilities which Xerces has (i.e. load the schema once; use it many times), in particular the JAXP 1.3 Validation API. See the FAQ here [1] on how to use the JAXP Validation API as well as this one [2] on general performance.
Thanks. [1] http://xerces.apache.org/xerces2-j/faq-pcfp.html#faq-4 [2] http://xerces.apache.org/xerces2-j/faq-performance.html Michael Glavassevich XML Parser Development IBM Toronto Lab E-mail: mrgla...@ca.ibm.com E-mail: mrgla...@apache.org Adrian Crum <adrian.c...@yahoo.com> wrote on 04/28/2009 10:56:32 PM: > Hello all. > > I'm trying to convert from DOM parsing to SAX parsing. The basic > code I'm using is: > > DocumentBuilderFactory factory = new org.apache.xerces.jaxp. > DocumentBuilderFactoryImpl(); > factory.setValidating(validate); > factory.setNamespaceAware(true); > factory.setAttribute("http://xml.org/sax/features/validation > ", validate); > factory.setAttribute("http://apache.org/xml/features/validation/schema > ", validate); > DocumentBuilder builder = factory.newDocumentBuilder(); > Document document = builder.parse(inputStream); > > for DOM parsing, and > > SAXParserFactory spf = new org.apache.xerces.jaxp.SAXParserFactoryImpl(); > spf.setValidating(validate); > spf.setNamespaceAware(true); > spf.setFeature("http://apache.org/xml/features/validation/schema > ", validating); > SAXParser parser = spf.newSAXParser(); > parser.parse(inputStream, handler); > > for SAX parsing. > > Using the same source XML file (that references an XSD, and is about > 68 KB), the SAX parsing runs 10 times slower than the DOM parsing. > If I disable the schema validation, the SAX parsing runs faster than > the DOM parsing - but the objects that are created are missing > default attributes specified in the XSD. (By the way, the same Java > objects are created in both scenarios - they have two constructors: > one for DOM and one for SAX.) > > Ideally, I would like to configure the SAX parser to just use the > XSD to supply default attribute values, and not use it for validation. > > I've Googled and searched the Xerces website for an answer, but I > didn't find one. I need the SAX parsing to run as fast or faster > than the DOM parsing with validation turned on. > > Can anyone help me? > > -Adrian > > --------------------------------------------------------------------- > To unsubscribe, e-mail: j-users-unsubscr...@xerces.apache.org > For additional commands, e-mail: j-users-h...@xerces.apache.org
