Rationale for library dependencies on default-jre or default-jre-headless?

[Hilko Bengen <bengen@debian.org>]

Hi!

The Debian policy for Java as shipped with java-common-0.52 states:

> 2.4. Java libraries
>
> [...]
>
>    Libraries must depend on the needed runtime environment
>    (default-jre and/or default-jre-headless if need a GUI or not).

What is the rationale for this?

IMO, in general, pure library packages (such as libjts-java) should not
care what JRE flavor is used to run their code.

Am I missing something?

Apparently, only a minority of lib*-java packages adhere to this policy,
anyway.

Cheers,
-Hilko