[sw360-dev] Some remarks about the transition to Java 11

["Michael C. Jaeger" <mcj@xxxxxx>]

hello,

  if you follow the open pull requests on github, you might have seen that there is some activity to update the infrastructure in future for sw360. The main goals are the following

* Moving to Java 11(coming from Java 8)
* Updating the reference Linux distro to Ubuntu 18.04 LTS (coming from 16.04). If we sorted that out, migration to 20.04 will be a lot easier.

Actually, the reference Linux choice is likely not a big limitation as it is possible to run sw360 natively on Mac or Windows computers as well. However, regarding the testing of the solution a common platform is always useful. After the codebase has been updated, then we will update:

* sw360vagrant
* Docker based builds

The Java 11 migration is not straight forward, because as seen in with our initials attempts [1],[2], not every dependency in our stack is compatible with Java 11. Most prominently the incompatibility of "some Liferays" with version > 11.0.5 of the JDK [3] (there is now 11.0.19)

As you might know, the main work for migrating from Java 8 to 11 is because of the dropping of packages after Java 8 which need to be installed separately. At the end, investing in all this work is a good investment, because we should be at latest stable versions for all of our dependencies anyway.

In order to have not a big chunk of changes, here is the detailed plan of how to go ahead:

* Update the Couchdb subsystem
* Update to Liferay 7.3.X
* Update all dependencies and code changes to run on a Java 11 JVM

-> sw360 version 11.0

* update of sw360vagrant (https://github.com/sw360/sw360vagrant/pull/31 )
* update of the docker based infrastructure build up

So, if you see problem or conflicts with this plan, please consider responding to this mail.

Kind regards,
  Michael 

[1] https://github.com/eclipse/sw360/pull/808
[2] https://github.com/eclipse/sw360/pull/916
[3] https://issues.liferay.com/browse/LPS-107983