Schema and ANY questions

[Jean-Louis Vila <jl...@cosmosbay.com>]

Hi,
I work since severals weeks on Schema structure&datatypes.

Many interrogations raise when I read WD 4/7 about "any" element.

1 - I found rules about any & namespaces very vague !
2 - When I define an ANY element in my Schema,
    in the instance document,how can we specify
    the encoding of the input fragment XML ?
3 - I guess that validating a schema instance with no targetNamespace
    and an any element with namespace="##local" will be
    impossible to realized!!
    I don't find any rule about this case.
4 - Case of schema defined with a targetNamespace and an "any"
    element defined with namespace="##targetNamespace"
    In an instance document, how can we detect that an element come from
    "any" element or an element explicitly defined in the schema ?
    Ex:
	----Here the schema----
    <schema ... targetNamespace="URI_TNS" xmlns:tns="URI_TNS">
    <element name="A" type="string"/>
    <element name="B">
      <complexType>
        <element ref="tns:A" minOccurs="0" maxOccurs="1"/>
        <any namespace="##targetNamespace" minOccurs="1" maxOccurs="1"
             processContents="strict"/>
     </complexType>
    </element>
    </schema>
	----Here an instance schema----
     <A>
       <B/> <!-- B is come from "any" or is it the first element of "A"
? -->
     </A>

	Results:
	 . if B is the first element of "A", this instance is non-valid.
	 . if B is the root element of "any", this instance is valid.
     Here is the problem !
     The only way to solve this problem, is to consider the "any" XML
document as
     self-supporting XML document. In this way, the "B" element will contain
     the definition of namespace in it (xmlns attribute).
     ----Ex1----
     <A>
       <B/> <!-- Here B is the first element of "A"
     </A>
	----Ex2----
     <A>
       <B xmlns="URI_TNS"/> <!-- Here B is the root element of "any"
element -->
     </A>

    So we can say:
	 Ex1 --> non-valid
	 Ex2 --> valid

Any opinions will be appreciated,
Jean-Louis Vila

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Re: Schema and ANY questions

[Eric Ye <er...@locus.apache.org>]

> Hi,
> I work since severals weeks on Schema structure&datatypes.
>
> Many interrogations raise when I read WD 4/7 about "any" element.
>
> 1 - I found rules about any & namespaces very vague !
> 2 - When I define an ANY element in my Schema,
>     in the instance document,how can we specify
>     the encoding of the input fragment XML ?

Why do you need to do that? the element from another namespace is just a
elment with
different namespace prefix, has to be physically appears in the same
instance document including
all its content.

> 3 - I guess that validating a schema instance with no targetNamespace
>     and an any element with namespace="##local" will be
>     impossible to realized!!
>     I don't find any rule about this case.
I didn't either,

> 4 - Case of schema defined with a targetNamespace and an "any"
>     element defined with namespace="##targetNamespace"
>     In an instance document, how can we detect that an element come from
>     "any" element or an element explicitly defined in the schema ?
>     Ex:
> ----Here the schema----
>     <schema ... targetNamespace="URI_TNS" xmlns:tns="URI_TNS">
>     <element name="A" type="string"/>
>     <element name="B">
>       <complexType>
>         <element ref="tns:A" minOccurs="0" maxOccurs="1"/>
>         <any namespace="##targetNamespace" minOccurs="1" maxOccurs="1"
>              processContents="strict"/>
>      </complexType>
>     </element>
>     </schema>
> ----Here an instance schema----
>      <A>
>        <B/> <!-- B is come from "any" or is it the first element of "A"
> ? -->
>      </A>
>

This not not valid since A's content is of type "string", which can't have
element content at all.
Perhaps you meant:
      <B>
        <A/> <!-- A is come from "any" or is it the first element of "B"
 ? -->
      </B>

in this case, the ACTUAL children of B element , which contains just a A
element,  matches the content model of  declared B , which is (A?,
any##targetNamespace?). It should match the first A? as far as I can rember.
Furthermore, it seems doesn't matter which one is actually matched.

> Results:
> . if B is the first element of "A", this instance is non-valid.
> . if B is the root element of "any", this instance is valid.
>      Here is the problem !
>      The only way to solve this problem, is to consider the "any" XML
> document as
>      self-supporting XML document. In this way, the "B" element will
contain
>      the definition of namespace in it (xmlns attribute).
>      ----Ex1----
>      <A>
>        <B/> <!-- Here B is the first element of "A"
>      </A>
> ----Ex2----
>      <A>
>        <B xmlns="URI_TNS"/> <!-- Here B is the root element of "any"
> element -->
>      </A>
>

Totally confused.....

_____


Eric Ye * IBM, JTC - Silicon Valley * ericye@locus.apache.org