Re: JRE not found, windows

[Markus Mützel]

Am 09. November 2019 um 18:54 Uhr schrieb "Nicholas Jankowski":
> > 32- or 64-bit Octave? (you didn't say)
> >
> > AFAIK the command 'system("java -version")' also works in case of a bit
> > width mismatch between Octave and Java as it is just a Windows command,
> > outside Octave.
> >
> > Philip
> >
> >
> both Octave and Java are 64bit.
>
> source files:
> jre-8u231-windows-x64.exe
> octave-5.1.0-w64.7z
>
> installed in usual locations.
>
> looking at how version checks for java,  i manually ran one of the checks
>
> >>  jname = javaMethod ("getProperty", "java.lang.System", "java.vm.name");
>
> error: javaMethod: could not find library or dependencies: C:\Program
> Files\Java\jre1.8.0_231\bin\server\jvm.dll
>
> yet i can cd to that folder and see it. i have no problem running Java
> from outside octave, so I don't think its a permissions error.
>
> frustrating...

This might be a red herring: But the error message is displayed for both 
ERROR_DLL_NOT_FOUND and ERROR_MOD_NOT_FOUND. The latter meaning that a 
dependency of jvm.dll couldn't be found.
Can you use e.g. Dependency Walker [1] to determine whether this is the case? 
It should be ok to ignore all dependency warnings on "core libraries" (like 
"kernel32.dll", "user32.dll", etc.).
I'm suspecting that the C runtime library might be not installed in the 
required version (or is somehow broken?).
AFAICS, Java 8 depends on MSVC 10.0 (2010). See e.g. here [2] for download 
links of the currently supported versions of the VCR.
I don't know though if it is possible to install Java without it checking that 
the necessary VCR is installed.

Markus

[1]: http://www.dependencywalker.com/
[2]: 
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads