java path in config

[HTSAXON]

I have different applications on the server that run in different Java versions

Solution I'd like
I want a variable called custom java path in which I can give the path of the JDK 1.8 supported version and it will help me to get rid of setting environment but on the server, I want to run different applications with different java versions

in short, there must be an optional option for Java path in its config

thanks