Testing XML Schema Location with Namespaces

XSD Tutorials - Herong's Tutorial Examples

∟XML Schema Location and Namespace in XML Documents

∟Testing XML Schema Location with Namespaces - JAXP

This section describes a tutorial example on how to validate an XML document with schema location assigned inside the XML document using the JAXP interface. Namespace is used in the schema and the XML document.

When a schema is assigned in an XML document with the "schemaLocation" attribute, the assigned schema will be considered as a hint by XML processors.

In fact, you use JAXP (Java API for XML Processing) 1.4 to perform schema validation, it will completely ignore the schema assigned in the "schemaLocation" attribute. Let's use XsdSchemaValidator.java described earlier in this book to test this.

Test 1. If the correct version of the schema is provided, hello_xsd_default_namespace.xml will pass the JAXP validation program:

herong> type hello_xsd_default_namespace.xml

<?xml version="1.0"?>
<p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns="http://herongyang.com"
 xsi:schemaLocation="http://herongyang.com hello_namespace.xsd">
Hello world!</p>


herong> java XsdSchemaValidator hello_namespace.xsd
^^^ hello_xsd_default_namespace.xml

Passed.

Test 2. If the incorrect version of the schema is provided, hello_xsd_default_namespace.xml will not pass the JAXP validation program. This test proves that XsdSchemaValidator.java totally ignores the schema specified inside the XML document.

herong> java XsdSchemaValidator hello.xsd hello_xsd_default_namespace.xml

Error:
   Line number: 4
   Column number: 65
   Message: cvc-elt.1: Cannot find the declaration of element 'p'.

Failed with errors: 1

Test 3. JAXP programs do check the namespace specified in the schema and make sure it matches the namespace used in the XML document. See the test below:

herong> type hello_namespace.xsd

<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 targetNamespace="http://herongyang.com">
 <xsd:element name="p" type="xsd:string"/>
</xsd:schema>


herong> type hello_xsd_namespace_wrong.xml

<?xml version="1.0"?>
<hy:p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:hy="http://herongyang.com/x"
 xsi:schemaLocation="http://herongyang.com/x hello_namespace.xsd">
Hello world!</hy:p>


herong> java XsdSchemaValidator hello_namespace.xsd
^^^ hello_xsd_namespace_wrong.xml

Error:
   Line number: 4
   Column number: 67
   Message: cvc-elt.1: Cannot find the declaration of element 'hy:p'.

Failed with errors: 1