Validate an XML File Against Multiple Schema Definitions

Question

I'm trying to validate an XML file against a number of different schemas (apologies for the contrived example):

• a.xsd
• b.xsd
• c.xsd

c.xsd in particular imports b.xsd and b.xsd imports a.xsd, using:

<xs:include schemaLocation="b.xsd"/>

I'm trying to do this via Xerces in the following manner:

XMLSchemaFactory xmlSchemaFactory = new XMLSchemaFactory(); Schema schema = xmlSchemaFactory.newSchema(new StreamSource[] { new StreamSource(this.getClass().getResourceAsStream("a.xsd"), "a.xsd"),                                                          new StreamSource(this.getClass().getResourceAsStream("b.xsd"), "b.xsd"),                                                          new StreamSource(this.getClass().getResourceAsStream("c.xsd"), "c.xsd")});      Validator validator = schema.newValidator(); validator.validate(new StreamSource(new StringReader(xmlContent))); 

but this is failing to import all three of the schemas correctly resulting in cannot resolve the name 'blah' to a(n) 'group' component.

I've validated this successfully using Python, but having real problems with Java 6.0 and Xerces 2.8.1. Can anybody suggest what's going wrong here, or an easier approach to validate my XML documents?

Answer 1

So just in case anybody else runs into the same issue here, I needed to load a parent schema (and implicit child schemas) from a unit test - as a resource - to validate an XML String. I used the Xerces XMLSchemFactory to do this along with the Java 6 validator.

In order to load the child schema's correctly via an include I had to write a custom resource resolver. Code can be found here:

https://code.google.com/p/xmlsanity/source/browse/src/com/arc90/xmlsanity/validation/ResourceResolver.java

To use the resolver specify it on the schema factory:

xmlSchemaFactory.setResourceResolver(new ResourceResolver()); 

and it will use it to resolve your resources via the classpath (in my case from src/main/resources). Any comments are welcome on this...

Answer 2

http://www.kdgregory.com/index.php?page=xml.parsing section 'Multiple schemas for a single document'

My solution based on that document:

URL xsdUrlA = this.getClass().getResource("a.xsd"); URL xsdUrlB = this.getClass().getResource("b.xsd"); URL xsdUrlC = this.getClass().getResource("c.xsd");  SchemaFactory schemaFactory = schemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI); //--- String W3C_XSD_TOP_ELEMENT = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n"    + "<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" elementFormDefault=\"qualified\">\n"    + "<xs:include schemaLocation=\"" +xsdUrlA.getPath() +"\"/>\n"    + "<xs:include schemaLocation=\"" +xsdUrlB.getPath() +"\"/>\n"    + "<xs:include schemaLocation=\"" +xsdUrlC.getPath() +"\"/>\n"    +"</xs:schema>"; Schema schema = schemaFactory.newSchema(new StreamSource(new StringReader(W3C_XSD_TOP_ELEMENT), "xsdTop"));