IBM's XML Parser for Java. XML4J for short. It is based upon the Apache Xerces Parser. IBM and the Apache foundation maintain a close working relationship so that the two contribute to one anothers codebase. Currently, XML4J is at version 3.1, and offers support for both SAX level 1 and W3C DOM level 1 parsing. Rudimentary support for SAX2, DOM level 2, and XML Schemas are in the works.