This section provides some errors from the XSD schema validation process on invalid XML files represented as SAXSource objects using the JAXP API.
In the previous section, we tested a valid XML file that conforms to the XSD schema file.
In this section, we will look at two invalid XML files and see how XsdSchemaSaxValidator.java
generates error messages.
The first invalid XML file has an extra node (element) inside "html":
>type first_html_extra_node.xml
<?xml version="1.0" encoding="utf-8"?>
<html>
<body>
<p>My first HTML document in XML format.</p>
</body>
</html>
>java XsdSchemaSaxValidator first_html.xsd first_html_extra_node.xml
Validator Class: com.sun.org.apache.xerces.internal.jaxp
.validation.ValidatorImpl
org.xml.sax.SAXParseException: cvc-type.3.1.2:
Element 'body' is a simple type,
so it must have no element information item [children].
The output shows that the "body" element has an extra children element,
which is not allowed by the schema.
The second invalid XML file has an extra attribute and an extra node (element) inside "html":
>type first_html_extra_attribute.xml
<?xml version="1.0" encoding="utf-8"?>
<html>
<body bgcolor="#eeeeee">
<p>My first HTML document in XML format.</p>
</body>
</html>
>java XsdSchemaSaxValidator first_html.xsd
first_html_extra_attribute.xml
Validator Class: com.sun.org.apache.xerces.internal.jaxp
.validation.ValidatorImpl
org.xml.sax.SAXParseException: cvc-type.3.1.1:
Element 'body' is a simple type,
so it cannot have attributes, excepting those whose namespace name
is identical to 'http://www.w3.org/2001/XMLSchema-instance'
and whose [local name] is one of 'type', 'nil', 'schemaLocation'
or 'noNamespaceSchemaLocation'. However, the attribute, 'bgcolor'
was found.
The error message in the output is very clear. The attribute "bgcolor"
is not allowed in the element "body".
However, the validator failed to report the second error that the "p" element
is not allowed inside "body".
If you compare XsdSchemaSaxValidator.java with XsdSchemaDomValidator.java,
you will see that the Validator instance handles validation errors in the same way
for both DOMSource objects and SAXSource objects.