List of major Java class file version numbers?

Question

I saw this list of major version numbers for Java in another post:

• Java 1.2 uses major version 46
• Java 1.3 uses major version 47
• Java 1.4 uses major version 48
• Java 5 uses major version 49
• Java 6 uses major version 50
• Java 7 uses major version 51
• Java 8 uses major version 52
• Java 9 uses major version 53
• Java 10 uses major version 54
• Java 11 uses major version 55
• Java 12 uses major version 56
• Java 13 uses major version 57
• Java 14 uses major version 58

Recommendations:

https://blogs.oracle.com/darcy/entry/source_target_class_file_version https://en.wikipedia.org/wiki/Java_class_file#General_layout

Answer 1

They come from the class version. If you try to load something compiled for java 6 into java 5 runtime, you get an error, an incompatible version of the class, get 50, expected 49. Or something like that.

See here at byte offset 7 for more information.

Further information can also be found here .

Answer 2

I found a list of Java class file versions on the Wikipedia page, which describes the format of the class file:

http://en.wikipedia.org/wiki/Java_class_file#General_layout

The offset of bytes 6 and 7 lists the versions with which the Java VM corresponds to them.