Java bytecode specification [closed]

Answer 1

The Java Virtual Machine Specification is a good place to start.

See Chapter 4 The class File Format. The updates cover new attributes added since the 2nd edition was made.

Answer 2

A new version of the specification has been released:

The Java Virtual Machine Specification, Java SE 7 Edition

This new addition does exclude the chapter on Java Programming Language Concepts which folks may or may not find useful. See here for that chapter in the Second Edition of the spec.

Answer 3

To start with, I suggest generating Java code from your language.

This will make reading and debugging much simpler.