I think writing it with asm library is much easier. Your code gets too long for a line coverage tool.
I'm not sure what you mean. If you're referring to the implementation, it's around three hundred lines [0], including the unfortunate problem I mention with visiting expressions, which doesn't seem like a lot.
Maybe you mean the instrumented code, but that doesn't matter -- it's meant to be generated, executed and thrown away. You would never have to look at it.
The original poster's article seems to be talking about a method that could be adapted to another language other than Java.