XML Commons Project
xml-commons was formed to hold common bits of XML-ish functionality that can be shared among other xml.apache.org projects. Currently, we maintain xml-apis.jar, which is a collection of widely-used externally-defined standards-based interfaces, like DOM, SAX, and JAXP. We also have a small number of XML related utilities.
For more information, see the official project pages at http://xml.apache.org/commons/