Re: Undetected JRE

[Bradley Kennedy]

Brad Kennedy
address@hidden
https://co60.ca

On 12/17/2017 04:44 AM, PhilipNienhuis wrote:
> Bradley Kennedy wrote
>>> On 2017-12-16, at 23:43, Daryl Lee <
>> daryl@
>> > wrote:
>>> Today I had yet another occasion to build up a Windows workstation from
>>> scratch.  When I got to the step of installing Octave (4.2.1) the
>>> installer told me it couldn't fine a Java JRE, even though I have Java
>>> 9.0.1 installed, as evidenced by the output of
>>>
>>>> java -version
>>> Is that anything for me to worry about?  At first glance, it looks normal
>>> (working GUI, working plots).
> Issues arise when mixing a 64-bit Octave with a 32-bit JRE, or vice versa.
> Did you check that?
>
> Last time I looked (years ago) OpenJDK builds for Windows proved to be very
> unstable.
>
>
>>  
>> Hi there Daryl,
>>
>> There should be (mostly) no issue. We ran Octave 4.2.1 on super computers
>> for months without Java due to a broken link. You obviously however, can’t
>> use Java based components.
>>
>> https://www.gnu.org/software/octave/doc/v4.2.1/Java-Interface.html#Java-Interface
>> <https://www.gnu.org/software/octave/doc/v4.2.1/Java-Interface.html#Java-Interface>
>>
>> I had a patch made at one point to let you change the Java directory at
>> run time (rather now it is set at compile time afaik) but I don’t think
>> anyone was interested in it.
> I can imagine that for Windows such a patch is obsolete as esp. on Windows
> the place where Java lives is very well defined and uniform across Windows
> versions, and easily uncovered by user programs.
> AFAICR from last time I installed Java, the installer didn't even allow to
> select the place where Java was to be installed.
>
> For Linux and OSX things are quite different.
>
> (Just curious) Where is that patch?
>
> Philip
>
>
>
> --
> Sent from: 
> http://octave.1599824.n4.nabble.com/Octave-Maintainers-f1638794.html
>
Patch was on a wiped work laptop. All it really did was change the path
that Java is searched for at runtime(or I guess launch time) using an
environment variable however. Should be easy to remake if someone is
interested. We only made the patch because we had Java root paths that
moved after installation.

In enterprise users may have multiple Java installed (even on Windows)
so it might be useful regardless. Not sure how this works if you change
the /version/ of Java with the environment variable however.