Good Documentation For JVM Bytecode?

[u/invokeinterface]

I really liked the idea of an intermediate bytecode language when I first learned that Java transpiles to one, so I tried to learn about it and got pretty far (using a hexeditor to mess around was pretty painful, though). I stopped because there isn't a lot of document for it like there is for Java, the best resources are I believe docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html and docs.oracle.com/javase/specs/jvms/se7/html/jvms-6.html, but I want to know if there are any others partly because these are kind of verbose and partly because it's just better to have more than two.

I know I won't ever really need to know any of this, and I don't intend to use any of this knowledge for making classes by hand, but I believe it would still be helpful in a milder sense to understand what the class files are "literally" doing. It helped with C

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[u/benevanstech]

You might find my book "The Well-Grounded Java Developer" (2nd Ed) interesting. There are several chapters on bytecode and related topics. I also have quite a few free resources on my website: https://kittylyst.com/ - some of which talk about bytecode.

[u/jivedudebe]

You can use javap you output the opcodes directly. Then there are tons of websites with lists of all the opcodes

[u/bowbahdoe]

This might be a good start https://jasmin.sourceforge.net/guide.html

[u/belayon40]

Check out the bytecode API from the last couple of JVMs. It took me a while to get the hang of it, but I used it extensively to build classes dynamically.

https://github.com/boulder-on/JPassport

Look in the code builder package.