This has been needed for deploying certain Clojure WAR files to Java application servers, before we quit and went to uberwar
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RT @nixcraft
On Linux you can do this to set a default java version/jdk:

update-alternatives --list java # list it
update-alternatives --display java # see default
sudo update-alternatives --config java # choose a new
man update-java-alternatives # read docs https://twitter.com/vwbusguy/status/1459305138514…
https://twitter.com/nixcraft/status/1459308621867614211