Develop Reference

Organizing XSDs in a JAR

I have the following structure in a JAR:
Products.xsd
ProductCommonTypes.xsd
/com
/foo
Products.class
When I do
schemaURL = Products.class.getClassLoader().getResource(schemaFile);
I see "Using schemaURL: jar:file:/C:/my.jar!/Products.xsd". I think this is good.
Later, I try to create a Schema and get an exception stating "Cannot resolve the name 'common:nonEmptyString' to a(n) 'type definition' component."
I believe that the problem is that it is unable to find common:nonEmptyString (which is in ProductCommonTypes.xsd) but can not figure out how to fix it.
Products.xsd
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:p="http://www.foo.com/Products"
targetNamespace="http://www.foo.com/Products"
xmlns:common="http://www.foo.com/ProductsCommonTypes"
elementFormDefault="qualified">
<xs:import schemaLocation="ProductsCommonTypes.xsd"
namespace="http://www.foo.com/ProductsCommonTypes"/>
<xs:element name="products">
<xs:complexType>
<xs:sequence>
<xs:element name="name" type="common:nonEmptyString" minOccurs="1" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
ProductCommonTypes.xsd
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.foo.com/ProductsCommonTypes"
xmlns="http://www.foo.com/ProductsCommonTypes"
elementFormDefault="qualified" >
<xs:simpleType name="nonEmptyString">
<xs:annotation>
<xs:documentation>A type that will require a non-empty string value be present
</xs:documentation>
</xs:annotation>
<xs:restriction base="xs:string">
<xs:pattern value="(\s*[^\s]\s*)+"></xs:pattern>
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="url">
<xs:annotation>
<xs:documentation>A HTTP URL</xs:documentation>
</xs:annotation>
<xs:restriction base="xs:anyURI">
<xs:pattern value="https?://.+"></xs:pattern>
</xs:restriction>
</xs:simpleType>
</xs:schema>
[jaxb - Unable to unmarshall from XSD which included other xsd
suggests adding all schema references, but I am working with many schemas that all import several other schemas. Seems like it could get ugly quick!
Is there a generic/dynamic solution that does not require me to identify and hardcode all schemas everytime I plan on working with one that might import others?
I plan to move all XSDs to a MyXSDs folder within the jar at some point. After moving them, will I have to do anything differently due to the location change?

Solution
I was able to solve this using an XMLCatalogResolver and creating an XML catalog file.
I moved all of my XSDs into a single folder and have the following structure in my JAR:
MyXSDs
Products.xsd
ProductCommonTypes.xsd
/com
/foo
Products.class
First, I created the catalog file and identified the schema that was being referenced.
<!DOCTYPE catalog
PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<public
publicId="http://www.foo.com/ProductCommonTypes"
uri="ProductCommonTypes.xsd"/>
</catalog>
Then, I created an XMLCatalogResolver that uses my catalog file and used it as the ResourceResolver for my SchemaFactory. It is important to note that the catalogs must be specified as an ordered array of absolute URIs as per the constructor's documentation.
// The catalogs must be an ordered array list of *ABSOLUTE* URIs
String[] catalogs = new String[] { xmlCatalogAbsPath };
XMLCatalogResolver resourceResolver = new XMLCatalogResolver(catalogs);
schemaFactory.setResourceResolver(resourceResolver);
You must specify the relative path to the XSD file. Therefore, because I put all of mine into a folder, I set relatativeSchemaPath="MyXSDs/Products.xsd" for use with ClassLoader.getSystemResource.
StreamSource streamSource = new StreamSource(ClassLoader.getSystemResource(relatativeSchemaPath).toString());
Schema schema = schemaFactory.newSchema(streamSource);

specify type for multiple IDREF attributes in JAXB bindings

Apologies if this is a duplicate question, but I could not find anything for my situation. So here goes:
I have the following in an xsd file:
<xs:complexType name="Allocation">
<xs:annotation>
<xs:documentation>Links its owner to an xs:id.</xs:documentation>
</xs:annotation>
<xs:attribute name="idRef" type="xs:IDREF"/>
</xs:complexType>
<xs:complexType name="XYZ">
<xs:sequence>
<xs:element name="SomeAllocation" type="Allocation"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="ABC">
<xs:sequence>
<xs:element name="SomeAllocation" type="Allocation"/>
</xs:sequence>
</xs:complexType>
I am try to generate fields/getters and setters in java that are of specific types for example XYZ.getSomeAllocation() should return type Object1 and ABC.getSomeAllocation() should return type Object2. The problem I am facing is that xjc is generating one Allocation class and the XYZ and ABC classes with the methods mentioned below returning java.lang.Object types.
Obviously creating to different Allocation types which are then used in the different objects solves the problem but I would like to reuse the object holding the xs:IDREF.
Your help is highly appreciated!
Thanks!

xjc: XML Validation issue

I am trying to generate java code using xjc.
My xsd is having following element
<xs:element name="DataRate">
<xs:attribute name="Limit" type="xs:decimal" use="optional" />
</xs:element>
and xjc is complaining with
[ERROR] s4s-elt-must-match.1: The content of 'DataRate' must match (annotation?, (simpleType | complexType)?, (unique | key | keyref)*)). A problem was found starting at: attribute.
After little investigation, i got to know that the attribute element is not wrapped with complexType and hence xjc is complaining. If I modify the xsd as
<xs:element name="DataRate">
<xs:complexType>
<xs:attribute name="Limit" type="xs:decimal" use="optional" />
</xs:complexType>
</xs:element>
it is working fine. But, as the xsd I am getting from 3rd party, I want to avoid the modification.
Is there any other way to do that?

Xml schema interfaces

I'm attempting to write an XML schema to define some model classes to be used in jaxb in java.
I would like to be able to define an interface in the xsd but I've no idea how to do this.
For example a lot of my classes will have an attribute called id which is type xs:ID. They will have an attribute called ref which is type xs:IDREF and they will have an attribute called extRef which means that there is a refrence but the element is not specified in the given xml file.
Ideally this would be an interface when converted to java for two reasons.
The classes that implement this are not necessarily connected.
I would like to specify a different inheritance tree for some of these objects.
Example:
<!-- Utility type to be externally referenceable this is too keep all the
externally refrencable attributes in check -->
<xs:complexType name="ExternallyReferenceable" abstract="true">
<xs:attribute name="extRef" type="externalReference" />
<xs:attribute name="id" type="xs:ID" />
<xs:attribute name="ref" type="xs:IDREF" />
</xs:complexType>
<xs:complexType name="ExternalCarPart">
<xs:extension base ="ExternallyReferenceable" />
</xs:complexType>
<xs:complexType name="CarPart">
<xs:extension base ="ExternalCarPart">
<xs:sequence>
<xs:element type="xs:string" name="partName" />
</xs:sequence>
</xs:extension>
</xs:complexType>
<xs:complexType name="CarLamp">
<xs:extension base ="ExternalCarPart">
<xs:sequence>
<xs:element type="xs:string" name="glassPurity" />
</xs:sequence>
</xs:extension>
</xs:complexType>
So in the above example it would be better if exteranllyRefrencable was an interface, and if carpart was an interface.
This would allow CarLamp to inherit from lamp rather than external car part. BicycleLamp could also implement the externallyRefrencable interface and extend lamp also.
Please ask me for clarification if the question isn't clear.

IIRC, JAXB doesn't generate interfaces from XSD.
JAXB also supports generating XSD from Java classes. I'm not sure what it does with interfaces in that regard, but perhaps you need to go at it in the opposite direction - begin with Java and generate XSD, though I'm not sure that will help you.

Java/XSD parsing

I doubt if there is something like this but I thought to ask though:
Does anyone know if there is a library in Java that reads an xsd file and "creates" the defined elements e.g. in a String format to use in the code?
E.g. read in the following schema:
<?xml version="1.0" encoding="utf-8"?>
<xs:schema elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="Address">
<xs:complexType>
<xs:sequence>
<xs:element name="Street" type="xs:string" />
<xs:element name="Town" type="xs:string" />
<xs:element name="Country" type="xs:string" minOccurs="0" />
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
And have a String in the following format:
<Address>
<Street></Street>
<Town></Town>
<Country></Country>
</Address>
Automatic tools do something similar, i.e. parse a WSDL and from the types section create for example JAXB classes that can be instances of the elements defined in schema.
Is there any library to do this?
UPDATE:
For example in Eclipse when creating an xml descriptor for a web application it presents a tree table with all the required elements for the users to fill in according to schema. How do they do it? I imagine they parse the xsds included in the jars
Any input is very welcome.
Thank you!

If its a WSDL file with which you want to generate Java classes, then Axis WSDL2Java (based on JAXB) can be used to get classes based on the schema defined in the WSDL.
JAXB also offers binding framework which you might want to look up.
http://publib.boulder.ibm.com/infocenter/wasinfo/v7r0/index.jsp?topic=/com.ibm.websphere.express.doc/info/exp/ae/twbs_jaxbschema2java.html
Above link should be useful.

oXygen has an XML instance generator that can generate a set of XML document samples based on a given XML Schema.
You can also invoke it from the commandline.