XMLJ is a Java XML Editor and validator project.
EasyML serialization library, to and from XML, similar to Gson
X3D is the open-standard format for 3D graphics scenes on the Web.
eXist-db is a feature rich Open Source native XML database
Java based XSLT Processor extension for syntax highlighting
XML Application Framework based on JAVA
NO LONGER MAINTAINED
EXI implementations in Java and C#
Create XML and JSON data services from any data source
CSV to XML converter
XMLUnit provides assertions that help testing code that produces XML.