I will try the redefine. I was actually hoping xsd's could behave almost like an object-oriented language in a way. I was hoping I could read in a car and validate it is a car, even though it was of type CompanyXCar. I can do that with Java API's left and right. Would be really nice to do it with XML api's too. Maybe I will repost again on the w3c lists and find my confusion that I had there. In the meantime I will try to find time and try the redefine element.
thanks,
dean
Sandy Gao wrote:
4 If there is an attribute information item among the element informationitem's [attributes] whose[namespace name] is identical tohttp://www.w3.org/2001/XMLSchema-instance and whose [local name] is type,then all of the following must be true: My namespace "is not" http://www.w3.org/2001/XMLSchema-instance,therefore 4.2 "does not apply" Note that the "whose" refers to the attribute ("xsi:type"), not its value. When there is an "xsi:type", a schema processor has to, required by the schema spec, resolve its value to a type definition. There is nothing Xerces (or any other schema processors) can do here. In the scenario you described, it seems to me that you shouldn't have used xsi:type in the first place, for the above reason. Have you considered my suggestion about using <redefine> at all? Sandy Gao Software Developer, IBM Canada (1-905) 413-3255 [EMAIL PROTECTED] Dean Hiller <[EMAIL PROTECTED] To: [EMAIL PROTECTED] m> cc: Subject: Re: dynamic validation, is this a bug 11/20/2003 02:18 PM Please respond to xerces-j-user thanks much sandy, but I am not exactly clear on that part of the spec. To make sure we are looking at the same part of the spec. Here is what I read and my interpertation below.... 4 If there is an attribute information item among the element information item's [attributes] whose [namespace name] is identical to http://www.w3.org/2001/XMLSchema-instance and whose [local name] is type, then all of the following must be true: 4.1 The ·normalized value· of that attribute information item must be ·valid· with respect to the built-in QName simple type, as defined by String Valid (§3.14.4); 4.2 The ·local name· and ·namespace name· (as defined in QName Interpretation (§3.15.3)), of the ·actual value· of that attribute information item must resolve to a type definition, as defined in QName resolution (Instance) (§3.15.4) -- [Definition:] call this type definition the local type definition; Notice #4....the namespace is identical to http://www.w3.org/2001/XMLSchema-instance and the end saying "all of the following must be true" referring to 4.1, 4.2...etc. My namespace "is not" http://www.w3.org/2001/XMLSchema-instance, therefore 4.2 "does not apply" I actually had this conversation with someone who was on the schema standards body and I got the impression that this was possible. Am I mistaken? I could not find anywhere in the spec that states a contradictory statement, neither have I found a supporting one yet. thanks, dean Sandy Gao wrote: ie. if it only knew about a car, it would process the car and ignore the Ford specific data, or Honda specific data depending on what type of car it actually received. But if your Honda car claims that "I'm a Honda, and you have to treat me as a Honda" (via xsi:type), then the schema processor has no choice but to tell you I'm sorry. The schema spec is very clear on this. When there is an xsi:type in the instance document, its value "must resolve to a type definition", which indicates that if such resolution fails, there is an error. You might want to consider <redefine>ing the "standard" schema, instead of extending it. This way, you don't need to specify "xsi:type" in your instance. And you can switch between the "standard" and the "redefined" schemas using an entity resolver (or grammar pool in Xerces). Hope this helps, Sandy Gao Software Developer, IBM Canada (1-905) 413-3255 [EMAIL PROTECTED] Dean Hiller <[EMAIL PROTECTED] To: [EMAIL PROTECTED] m> cc: Subject: Re: dynamic validation, is this a bug 11/20/2003 10:06 AM Please respond to xerces-j-user yeah, can't really do that seeing as how the protocol is a standard(ie. The whole xsd down below is the standard and we want to extend it and add a proprietary feature the protocol doesn't have due to customer requests), and you know how slow standards change. I really need to accomplish it by extension. Should I ask the xerces developers then???? I personally don't like the any element and much prefer the object oriented-ness of schemas where you can extend other base types and add data to them though I haven't gotten them to work yet. ideally, an application would just ignore extra data. ie. if it only knew about a car, it would process the car and ignore the Ford specific data, or Honda specific data depending on what type of car it actually received. thanks, dean Mike Rawlins wrote: At 05:27 PM 11/19/2003 -0700, Dean Hiller wrote: good question. did a quick grep...processContents is not found in the entire schema(schema is 300 pages). Root element looks like so <xsd:element name="Root" type="RootType/> <xsd:complexType name="RootType"> <xsd:sequence> <xsd:element name="Element" type="ElementType"/> </xsd:sequence> </xsd:complexType> <xsd:complexType name="ElementType"> <xsd:sequence> <xsd:element name="data1" type="xsd:string"/> </xsd:sequence> </xsd:complexType> Hmm, not quite what I was expecting. If you want to play around with another approach, you might instead do something like: <xsd:complexType name="ElementType"> <xsd:sequence> <xsd:element name="data1" type="xsd:string"/> <xsd:any namespace="##any" processContents="skip"> </xsd:sequence> </xsd:complexType> Then, in your instance document try: <Element> <data1>some data</:data1> <ava:data2>more data</ava:data2> </Element> I'm not sure I've got the syntax exactly correct, but this may be closer to what you want and at least get you started. This is approach, of course, just deals with the instance document and schema. I've had a few problems with a similar approach with Xerces, but didn't have time to track them down to closure. However, this or something similar *should* work. Mike --------------------------------------------------------------- Michael C. Rawlins, Rawlins EC Consulting www.rawlinsecconsulting.com Using XML with Legacy Business Applications (Addison-Wesley, 2003) www.awprofessional.com/titles/0321154940 --------------------------------------------------------------------- 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]
