I'd lay odds they've recently been trying to use Java directly given post history and the, shall we say, less than clear update instructions in the OP.
I'm going to use this reply as an excuse to expand the bit in my earlier post about not keeping an installed version of Java and want to be clear that the following bit is general information for anybody reading the thread, not any sort of comment on anybody. Also, I'm most certainly not a programmer.
Java has been around for a while. There are multiple vendors, versions, and a whole slew of long running legal disputes that make it less than the universal platform it was envisaged as back when computers were beige. Beyond this, anything that has been in development for a while can use parts that become deprecated and, eventually, removed. Going through a project to deal with that can be a lot of work and doesn't always provide any gain, so a developer might continue with the old version and distribute the runtime that will work as part of a unified download.
With all the variation possible before even considering any specific modifications that could have been made it may be best to think of Java like you might a game engine - you could have UE/Unity/RPGM/Fnord installed and fully up to date but that doesn't mean you can just run any game made with it using that as the runtime.
TL;DR.
Don't install Java systemwide unless you absolutely have to. Don't install JDK unless you absolutely have to and hate yourself.