[arch-general] How to have multiple JDKs parallel?

[Guillaume ALAUX]

On Mon, Sep 17, 2018 at 5:48 PM Carsten Mattner via arch-general
<arch-general at archlinux.org> wrote:
>
> On 9/17/18, Eli Schwartz via arch-general <arch-general at archlinux.org> wrote:
>
> > So essentially what you really want is a way for pacman to remember your
> > choice. That would require pacman modify its configuration which is
> > something that goes against the current architecture... What would happen
> > instead is pacman.conf could be used to configure this.
> >
> > I'm not sure if IgnorePkg or HoldPkg would have an effect here...
>
> The way I read it, what's being suggested is something like Debian's
> update-alternatives. https://wiki.debian.org/DebianAlternatives
>
> Or a JVM version manager ala pyenv etc. Not sure.

Just to give some backing: here is the official explanation of what
has already been stated before about JDK versions:

"[…] non‑LTS releases are considered a cumulative set of
implementation enhancements of the most recent LTS release. Once a new
feature release is made available, any previous non‑LTS release will
be considered superseded. For example, Java SE 9 was a non‑LTS release
and immediately superseded by Java SE 10 (also non‑LTS), Java SE 10 in
turn is immediately superseded by Java SE 11." [0]

So keeping OpenJDK 9 in our repo while OpenJDK 10 is out would be the
same as keeping say OpenJDK 8.u181 while OpenJDK 8.u182 is out! Even
though I can understand the (developer) use case, this is clearly out
of Arch Linux' scope.

[0] http://www.oracle.com/technetwork/java/javase/eol-135779.html

Guillaume