The jPOS Common Message Format specification is getting an update. CMF v3 is still a work in progress, but an early-access draft is available at jpos.org/doc/jPOS-CMFv3.pdf for anyone who wants to follow along. The most significant addition in v3 is first-class support for the ISO 8583 dataset model—and that's what this post is about.
Since ISO 8583:2003, the standard has defined three types of data elements: primitive, constructed, and composite. Primitive and constructed fields have always had first-class support in jPOS. The third type—composite fields—has historically been treated as opaque binary blobs, with application code responsible for parsing their contents manually.
jPOS 3.0.2 changes that.
The jPOS tutorial has been expanded with several new sections covering some of the most commonly used — and most commonly misunderstood — parts of the framework.