In Eclipse, if you get this error:
Caused by: java.lang.UnsupportedClassVersionError: MyLanguage/strategies/InteropRegisterer has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
It is caused by Eclipse internally compiling using the wrong Java version. Go to the Eclipse Preferences (Cmd+, on macOS), Java ‣ Compiler and set the Compiler Compliance Level to
1.8 (which corresponds to class file version 52.0).