JAXP 1.4 is now final. This is a "maintenance release" (JSR 206) but a substantial one. The main new addition is support for StAX (JCP, wikipedia) but there are other changes too (Change Log). This is the same version that goes into Java SE 6; you can also use it with JRE 1.4 and JRE 5.0 using the Endorsed Standard Override mechanism.

The implementation is delivered as two JARS (API + Impl) for simplicity and uses the StAX and JAXP implementations from GlassFish which build on Xerces 2 Java. Check the blogs from Santiago and Norm for some more details.

All this code is Open Source, and so will be the implementation of the next version of the spec.

Like earlier versions, the JAXP 1.4 API (Java.Net OSS project, spec, JavaDocs) includes a pluggability layer to switch implementations using a Factory pattern. The whole area is not very well understood by the developers, and Santiago's detailed blog provides a very good summary.

The intrinsic problem is that this is an area where the spec can be improved, so start preparing your feedback for the next version of the spec... we are going to do it all at Java.Net and a main focus will be improved usability.

We continue to add GlassFish components to the Java.Net Maven Repository: Santiago reports that JAXP 1.4 (part of Java SE 6 (Mustang)) is the latest Addition to the Maven Repository.

Earlier additions to the repository include: Java Persistence and EJB 3.0, JSTL 1.2, Servlet 2.5 and JSP 2.0 and JSP 2.1, XML Stream, Fast Infoset, JSFs, JavaMail and Activation, JAXB, JAX-WS and SAAJ.