Get java class version from javac or JRE without a compiled class

Question

Java class version can be obtained from a class binary using javap

javap -verbose Test | grep 'minor\|major'
  minor version: 0
  major version: 55

Is it possible to know in advance which class version a JDK will produce? java -version does not show it

java -version
openjdk version "11.0.17" 2022-10-18

Usually related to java.lang.UnsupportedClassVersionError .

Answer 1

Java class major/minor version produced by a JDK can be obtained from java command as follows

java -XshowSettings:properties -version 2>&1 | grep -E 'java.(class.)?version '

Result

java.class.version = 55.0
java.version = 11.0.17