Validating and non validating xml parser
I'm running into real difficulties validating XML with XSD.
I should prefix all of this and state up front, I'm new to XSD and validation, so I'm not sure if it's a code issue or an XML issue.
To see what happens when the XML document does not specify a DTD, remove the declaration. Because you don't yet have one, it's value is null.
In other words, the message is saying that you are trying to validate the document, but no DTD has been declared, because no declaration is present. (In the next section, you'll learn how to define parameter entries so that we can use XHTML in the elements we are defining as part of the slide presentation.) It is important to recognize that the only reason an exception is thrown when the file fails validation is as a result of the error-handling code you entered in the early stages of this tutorial.
By now, you have done a lot of experimenting with the nonvalidating parser.
Because JAXP-compliant parsers are not namespace-aware by default, it is necessary to set the property for schema validation to work.If the parser is not 1.2-compliant and therefore does not support XML Schema, it can throw a Note: You'll learn about namespaces in Validating with XML Schema.For now, think of these attributes as the "magic incantation" you use to validate a simple XML file that doesn't use them.(If a combination is not supported by a particular implementation, it is required to generate a factory configuration error.) Although a full treatment of XML Schema is beyond the scope of this tutorial, this section shows you the steps you take to validate an XML document using an existing schema written in the XML Schema language.(To learn more about XML Schema, you can review the online tutorial, Note: There are multiple schema-definition languages, including RELAX NG, Schematron, and the W3C "XML Schema" standard.