GooeySAX

GooeySAX is a cross-platform tool that wraps an underlying SAX parser (Apache Xerces, to be exact) in a Java Swing interface. Use GooeySAX to parse XML documents on your local file system or across the network to determine their Well-Formedness.

With the optional Validity setting enabled, you may also validate your document against a DTD or W3C XML Schema.

GooeySAX is the perfect tool for the web author who cares! Checking your XHTML document's validity either locally or remotely is a snap, and GooeySAX's detailed error messages let you know about those embarassing validation errors immediately.