RFR: 8221610: Resurrect (legacy) JRE bundle target

[Langer, Christoph]

Hi build-dev,

today I’m coming up with kind of a backward oriented suggestion… don’t know how well that would be received. Let’s see.

For JDK 11, with JDK-8200132 [0], the JRE build has been moved to legacy.
There has been some discussion beforehand whether the JRE build can completely be dropped or how far one can go removing the support for it [1]. In the end the decision was made to at least remove the JRE from the main targets and only offer some “legacy” targets that would still build the JRE. Unfortunately, you were under the assumption that nobody except Oracle would use the bundle target and removed it as well [2]. Unfortunately, this assumption was not quite true (and I was not there to raise my concern ☹). In SapMachine builds, we use the bundle targets and we are also still building JRE images for several stakeholders. So it would really be good if we could get the JRE bundle target back. At the moment we mimick the bundling in a shell script that is run after the build.

So, I suggest to add back the BUILD_JRE_BUNDLE target in Bundles.gmk and add an additional main target called legacy-bundles which can be called for creating the JRE bundle.

Of course, this can go eventually when JRE support is finally dropped for OpenJDK.

Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8221610.0/
Bug: https://bugs.openjdk.java.net/browse/JDK-8221610

Thanks
Christoph

[0] https://bugs.openjdk.java.net/browse/JDK-8200132
[1] https://mail.openjdk.java.net/pipermail/build-dev/2018-June/022249.html
[2] https://mail.openjdk.java.net/pipermail/build-dev/2018-June/022274.html