Java SE (Java Platform, Standard Edition)

Hi,

i'm running a computer lab for students. I've installed JDK 9 and JDK 1.8 in parallel.

I notice there's an entry in the system-wide PATH:

C:\ProgramData\Oracle\Java\javapath

Examining this i see it's a NTFS junction 'pointing' to a sub directory

C:\ProgramData\Oracle\Java\javapath_target_5613875

which in turn contains the Java 9 executables java.exe, javaw.exe and jawaws.exe

I must admit i don't uderstand this. Seems to be useful to switch the JDK versions, but:

• how to?  ( as a student with normal user rights...)
• why does the junction point to a sub directory which holds copies of these three excutables, not to C:\Program Files\Java\jre-9.0.x\bin?

Thanks for any advice...