fix java version in install script

[tischi]

@axtimwalde @mkitti

In this script: https://github.com/saalfeldlab/n5-utils/blob/master/install

Is there a way to fix the java version in a way that would work both on a Mac and on Linux?

I have the issue that I need to run such installations scripts on computers that have multiple JDK installed....

[mkitti]

I'm unclear what you mean by "fix". Do you want to set it to be a constant value? Or is this broken on Mac or Linux?

I think the java selected could be influenced by the PATH environment variable and/or symlinks. Perhaps the other way would be to look for the JAVA_HOME environment variable.

Also cc: @bogovicj

[tischi]

Do you want to set it to be a constant value?

Yes, because some SciJava things don't yet run with Java > 8

Ah and there is another issue with UseConcMarkSweepGC, but I see you have solved it already:

if [[ $(java -version 2>&1 | grep version) =~ 1.8 ]]
	then
		echo '  -XX:+UseConcMarkSweepGC \' >> n5-view