How to find out the Java version of a compiled class file

It has been confirmed up to Java10 (as of 2018/08/01).


javap -v file.class | grep "major version" | awk '{ print $3 - 44 }'


The major version value displayed by the javap -v command seems to be the" supported class version "(≠ Java version). The class version is "Java version +44", so you can subtract it.

Java maintains compatibility = supports all previous "supported class versions" It seems like that.


It is unclear what will happen after Java 9 because the versioning method will change. Will there be a beta version of the future version someday?

2018/03/12 postscript

It seems that the version notation after Java 10 is as ↓. I don't know how it actually comes out with java -version, but for reference.


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