Parser doesn t support setschema not validating
There are multiple ways to validate input, and this article will look at two of them: Document Type Definitions (DTD) and XML Schema (XSD).A third option is Relax NG, which tries to find a middle ground between DTD's lack of expressiveness and XSD's Byzantine structure. Before continuing, I want to add a third, non-standard term to describe XML documents: “correct.” A validator can only check the existence, ordering, and general content of an XML file; it's equivalent to the syntax check of a Java compiler.Note that in this example, even when the XML content of the file matches the XSD format, the payload that is passed on forward is null.After validating that the content is correct, it is not passed on forward.Except for one small problem: the Namespace spec was introduced in 1999, while the DOM level 1 spec was released in 1998 and knew nothing of namespaces.The JDK's XML API predated namespaces, and due to backwards compatibility you must explicitly tell it that you want namespace-aware parsing: , not the parser.
Normally, this isn't an issue, especially if the XML is both produced and processed within the same organization.
But for everything else (including new code using XPath), namespace-aware parsing should be your default.
There are two terms applied to XML documents that sound the same but have very different meanings: “well-formed” and “valid.” A document is well-formed if it can be parsed by a parser: all the opening elements have corresponding closing elements, text content has been properly escaped, the encoding is correct, and so on.
I recommend always parsing with namespaces enabled, with one exception: in legacy code that uses XPath or XSLT.
As I describe elsewhere, XPath has its own hoops with regard to namespaces.