The Xerlin project is a Java based XML editor that can run on any Java 2 virtual machine. The application is extensible via custom editor interfaces. Xerlin can be used to provide simple, intuitive interfaces for users who know nothing about XML.
Butterfly XML Editor is an IDE built on top of a new real-time incremental XML parsing algorithm. The editor features syntax and error highlighting, incremental validation, code completion, XSLT pipelines, and side by side DOM and source viewing.