I want to create a custom processing plugin for ES and I ran into the problem that apparently building anything for ES 7.7.0 requires Java 14 ( see https://github.com/elastic/elasticsearch/pull/54696 ).
Yet the https://www.elastic.co/support/matrix#matrix_jvm states runtime 1.8 is still supported and also it states
Java 9, Java 10, Java 12, and Java 13 are short term releases. We advise against using them unless you're prepared to handle the fast release cadence this imposes.
What is the point of requiring a javac several versions newer than what the output binaries (runtime) should support?