Understanding Xerces Schema object model...

["P. Ramesh" <pr...@quark.co.in>]

Greetings group,

How can I use the Schema parsing API(XS API) to retrieve the components of a
Schema given a element so that:  
1) To get Global element constructs in a given schema file.
2) To get either a element declaration to get its further child constructs.
3) To know whether an element construct is of type SimpleType or
ComplexType.
4) To know an elements construct's informatin like (name, datatype, its
value if textnode, enumeration values if any, default     if any, content
model like required or not?, min and max occrances, attributes info).
5) To know an attribute construct's informatin like (name, datatype, its
value, enumeration values if any, default if any,  content model like
required or not?, derived from restriction/union/list).

I was using XPath API in Xerces previously but considering the complications
in the incude/import constructs I have started exploring Xerces API (API of
ASModel , XS and PSVI). I could not find any examples that tell how to
process(Not parse plz!!!) a schema using XSSchemaGrammar retrieved from a
XSSchemaLoader.loadGrammar(...). I could not explore beyond XSSchemaGrammar
as at every place in
XSElementDeclaration/XSTypeDefinition/XSSimpleTypeDefinition/XSComplexTypeDe
finition, etc classes there are references to PSVI Interfaces/classes. It
would be very nice if you can throw some light on the dependencies of these
packages.  

******************************** 
*The Use Case is detailed below* 
********************************

The user supplies an XML Schema file as listed below:

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema targetNamespace="http://my-company.com/namespace"
xmlns="http://my-company.com/namespace"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified"
attributeFormDefault="unqualified">
	<xsd:element name="Person">
		<xsd:complexType>
			<xsd:sequence>
				<xsd:element name="First"
type="xsd:string"/>
				<xsd:element name="Last" type="xsd:string"/>
				<xsd:element name="Title" type="xsd:string"
minOccurs="0"/>
				<xsd:element name="PhoneExt">
					<xsd:simpleType>
						<xsd:restriction
base="xsd:int">
							<xsd:maxInclusive
value="999"/>
						</xsd:restriction>
					</xsd:simpleType>
				</xsd:element>
				<xsd:element name="EMail"
type="xsd:string"/>
			</xsd:sequence>
			<xsd:attribute name="Manager" type="xsd:boolean"
use="required"/>
			<xsd:attribute name="Programmer" type="xsd:boolean"
use="optional"/>
			<xsd:attribute name="Degree">
				<xsd:simpleType>
					<xsd:restriction base="xsd:string">
						<xsd:enumeration
value="BA"/>
						<xsd:enumeration
value="MA"/>
						<xsd:enumeration
value="Ph.D"/>
					</xsd:restriction>
				</xsd:simpleType>
			</xsd:attribute>
		</xsd:complexType>
	</xsd:element>
</xsd:schema>

************
*End Result*
************
The schema is shown visually in a java tree(JTree object).
Then I would like to show it something like

	-- Person
	   -- <at>Manager
	   -- <at>Programmer
	   -- <at>Degree
	   -- <,>                               <-- represents a sequence
		   -- <el>First
		   -- <el>Last
		   -- <el>Title
		   -- <el>PhoneExt
		   -- <el>EMail

When the User selects a schema node in JTree. The properties of the node
would be shown to user 
Eg :
 When the user selects the Programmer node in the tree.
 The Properties :- 
 Data Type : boolean
 Use : Mandatory  
 
Thanks in Advance,
--Ramesh

---------------------------------------------------------------------
To unsubscribe, e-mail: xerces-j-user-unsubscribe@xml.apache.org
For additional commands, e-mail: xerces-j-user-help@xml.apache.org