Hi, thank you all for these interesting thoughts!
Gareth (now Chair of of Apache Xerces Project Management Committee) stated that Xerces does not claim to validate Schemas and that I should hence try another tool. (http://blog.parthenoncomputing.com/xerces/archives/2005/04/can_i_validate.html) Jeff had the idea of using the grammar preparsing mechanism to validate schemas. I like the idea from the point of view that I want to benchmark Xerces validation performance in a B2B scenario. Therefore precaching is imho required anyway for increased performance in message validation. The benchmark however relies on the XML Schema test collection available here (http://www.w3.org/2001/05/xmlschema-test-collection.html). In the past, xerces (2.0.0_beta4) was only tested in test cases that involved a schema and an instance. Please share with me your thoughts on: 1. ) Did anybody try to run the W3C schema-only test cases on Xerces (using the precaching framework)? 2. ) Is the precaching framework suitable for running the above benchmark? 3. ) Will Schema validation be added to Xerces (the last question is interesting for the "outlook"-part of my paper since I want to compare Xerces with an OpenSource Tool developed by my company). Thank you Gareth, Jeff and Bob for your previous answers. Kind Regards, Gregor @Gareth: This is how I came up with the idea of using the Schema for Schema with Xerces (it was silly, but I gave it a try :-) >From XSV homepage (http://www.w3.org/2001/03/webdata/xsv) ...This means that if the only input is a schema document, XSV normally just validates that document against the Schema for Schema Documents (XMLSchema.xsd), but does not also check the Schema REC's constraints on the corresponding schema... > Xerces will validate your schema if you cause it to be parsed with the > appropriate parser features set. The necessary features are discussed > on the Features page of the documentation and the XML Schema FAQ. You > can force the schema to be read > 1. by parsing an instance document whose root element is in the > namespace of your schema (and one of the typical means is specified for > the parser to find the schema for that namespace) or > 2. by using the grammar preparsing mechanism (see the Caching and > Preparsing Grammars FAQ) > > The validation features set in the parser determine which constratints > on the schema are checked. You should almost certainly provide a custom > error handler to the parser to get good error reporting. > > You don't need to worry about the schema-for-schemas. Xerces treats > that as a built-in. > > All the doc pages mentioned can be accessed from the root of the xerces > documentation tree. > > Jeff > > Bob Schloss wrote: > > >Be aware that not all the constraints which XML Schemas must follow can > be > >syntactically checked only using the Schema for XML Schema. > > > >You may want to process your schema with some very complete Schema > checking > >tool. See, for example, the XML Schema Quality Checker located on IBM > >alphaWorks [1] or XSV [2]. > > > >Bob > > > >[1] http://www.alphaworks.ibm.com/tech/xmlsqc > >[2] http://www.w3.org/2001/03/webdata/xsv > > > > > > > > > > > > > "Gregor" > > > <[EMAIL PROTECTED] > > > an.com> > To > > [EMAIL PROTECTED] > > > 04/14/2005 01:49 > cc > > AM > > > > Subject > > How to validate an XSD File > > > Please respond to (validating a (not against a) > > > xerces-j-user Schema) > > > > > > > > > > > > > > > > > > > > > > > > > > > > >Hello, > > > >I am trying to validate Schema files using Xerces. > > > >The problem is, that I only got one XML Schema file e.g. attA001.xsd > (some > >will now, this is the W3Cs Schema-test-collection > >http://www.w3.org/2001/05/xmlschema-test-collection.html) and want to > tell > >whether it is a valid XML Schema according to XML Schema recommendation > or > >an invalid one. > > > >I tried the following approaches: > > > >1.) Download the Schema-for-Schemas from the W3Cs Website > >("http://www.w3.org/2001/XMLSchema.xsd";) and validating attA001.xsd > against > >this file as if attA001.xsd was an instance (which technically in my > >understanding it is) of XMLSchema.xsd > >(Please see code snippet below) > >(Before doing that I validated the XMLSchema.xsd against its own internal > >dtd which worked just fine) > > > >2.) Validate an empty file specifing attA001.xsd as Schema file for it > >(hope > >it would appart from empty file err also point to errors in the schema > >(..schema-full-checking", true); but it did not. > > > >I ran out of ideas at some point yesterday night. > > > >I am very thankfull for any suggestions. > > > >Kind Regards, > > > >Gregor > > > >1.) Code Snippet > >This is the setup: (try/catch omitted for legibility) > > > >SAXParserFactory factory = SAXParserFactory.newInstance(); > > > >SAXParser parser = factory.newSAXParser(); > > > >XMLReader reader = parser.getXMLReader(); > > > >reader.setFeature("http://xml.org/sax/features/namespaces";, true); > > reader.setFeature(" > >http://xml.org/sax/features/namespace-prefixes";, > >true); > > > >reader.setFeature("http://xml.org/sax/features/validation";, true); > > > >reader.setFeature("http://apache.org/xml/features/validation/schema";, > >true); > > > >reader.setFeature(" > >http://apache.org/xml/features/validation/schema-full-checking";, > >true); > > > >Validator handler=new Validator(); > >reader.setErrorHandler(handler); > > > >parser.setProperty > >("http://java.sun.com/xml/jaxp/properties/schemaLanguage";, > > "http://www.w3.org/2001/XMLSchema";); > > > >parser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaSource";, > > "C:/test/XMLSchema.xsd"); > > > >parser.parse(SchemaUri, handler); > >//SchemaUri = "C:/test/attA001.xsd" > > > >This is the errorMsg: > > > > s4s-elt-invalid-content.1: The content of '#AnonType_documentation' is > >invalid. Element 'attribute' is invalid, misplaced, or occurs too often. > > > >Line Number:1277 > > > >I can not find the specified element and I get the same error for many > xsds > >I am trying to validate (even the ones supposed to be valid according to > >W3Cs XML Schema test collection) > > > >--------------------------------------------------------------------- > >To unsubscribe, e-mail: [EMAIL PROTECTED] > >For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > > > >--------------------------------------------------------------------- > >To unsubscribe, e-mail: [EMAIL PROTECTED] > >For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
