Hi, I am very pleased to announce the immediate availability of the
JDO extensions for the Castor XML code generator in form of a *technology preview* as part of the first snapshot release of Castor 1.3.1, which can be found at and downloaded from the snapshot repository of the Codehaus at http://snapshots.repository.codehaus.org/org/codehaus/castor ** Motivation ** With Castor 1.3 and previous releases it it has always been possible to generate Java classes from an XML schema and use these classes for XML data binding without having to write a mapping file. This is possible because the Castor XML code generator generates - in addition to the domain classes - a set of XML descriptor classes as well, with one descriptor class generated per associated domain class. It's this XML descriptor class that holds all the information required to map Java classes and/or field members to XML artefacts, as set out in the original XML schema definitions. This includes .... - artefact names - XML name space URIs - XML name space prefix - validation code In addition, it was already possible to use the generated set of domain classes in Castor JDO for object-/relational mapping purpose by supplying a (manually written) JDO-specific mapping file. Whilst technically not very difficult, this was still an error-prone task, especially in a context where tens or hundreds of classes were generated from a set of XML schemas. ** JDO extensions and XML schema annotations ** The JDO extensions for the Castor XML code generator extend the code generator in such a way that - based on Castor JDO-specific annotations being added to your XML schema - a second set of descriptor classes is generated: the JDO descriptor classes. These new descriptor classes define the mapping between Java (domain) objects and database tables/columns, and as such remove the requirement of having to write a JDO-specific mapping file. Please find an extended introduction to the general principles at http://www.castor.org/reference/html/jdo.extensions.html where you'll find information about - The XML schema artefacts available to annotate an existing XML schema - Small examples to highlight the usage of these artefacts. - A (limited) set of current product limitations. Regards Werner Guttmann --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email
