complete WP1

[egonw]

Description:

WP1 will be focusing on the CDK library itself, the other on updating the tools using
the CDK. The CDK library is built with Apache Maven, but the Maven modules show a
complex dependency tree, where the more core modules have fewer dependencies on
third-party libraries. This modularisation, however, needs upgrading. OSGi bundles are
already created by Maven, but the bundle content does not yet match the standard
and one Java package can be split over multiple bundles. Second, we wish to improve
the maintainability of the library and improve the code coverage of the (unit) testing to
at least 50% for all modules (statistics available at app.codecov.io/gh/cdk/cdk). Third,
the CDK will be updated to compile with Java 21 (which it currently does not).

• Improve the dependencies of the Maven modules #5
• Improve testing coverage #6
• Upgrade the CDK to be a good Java 21 citizen #7