RFE to re-purpose option --version:<version>

[Mandy Chung]

If you are only looking for the version, would JAVA_VERSION satisfy your need? JAVA_FULL_VERSION is only present in JDK and JRE image but not custom image since the property is supplied by the jdk build.

Mandy

> On Aug 9, 2016, at 9:49 AM, Paul Benedict <pbenedict at apache.org> wrote:
> 
> No, I haven't considered that. Thank you, Mandy. Good tip. And I see that file also contains JAVA_FULL_VERSION, whose value is identical to the -fullversion option output.
> 
> Cheers,
> Paul
> 
> On Tue, Aug 9, 2016 at 11:40 AM, Mandy Chung <mandy.chung at oracle.com> wrote:
> 
> > On Aug 8, 2016, at 8:51 AM, Paul Benedict <pbenedict at apache.org> wrote:
> >
> > However, I would like to propose bringing back the option with a different
> > purpose. I would like to use --version:<version> as a validation check. I
> > want Java to execute ONLY if the version specified matches the actual
> > platform version. This would be a wonderful help to scripts that require a
> > particular version of the Java platform, and should fail if the environment
> > has been accidentally setup with the wrong Java platform version.
> >
> > Examples:
> > java --version:9
> > java --version:9.1
> >
> > AFAICT, the only way to do this now is to execute Java twice. Once to pipe
> > --version to some find/grep command and check return code, and then execute
> > java again if the check pass. Loading the runtime twice is not optimal,
> > wouldn't you agree? Yet if you agree to this proposal, it would be a big
> > win for script writers, I believe.
> 
> Have you considered checking the JAVA_VERSION property in $JAVA_HOME/release file?  jlink creates the `release` file containing certain properties about the runtime image.
> 
> Mandy
>