Hacking Java Bytecode for Programmers (Part 2)

Re:Hacking Java Bytecode for Programmers (Part 2) by maxbaroi on Friday May 17, 2013 @02:17PM (#5725886)

I'm not being facetious. I don't know anything about the implementation of the JVM or its byte-code, and was hoping to learn a bit. But...

1. How was I supposed to know 0x19 was the relevant byte to look at? I know there should be a load opcode somewhere, how do I know it was that 0x19?

2. What's going on between the load opcode, and the actual string data about 120 bytes apart?

3. Is looking up the definition of an opcode from a list really a mnemonic device?

Maybe that last bit was a bit facetious.

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Re:Hacking Java Bytecode for Programmers (Part 2) by jfolkins on Friday May 17, 2013 @02:24PM (#5725932)

Yeah, I'll clarify that bit. Basically I'm trying to convey.

- Opcodes exist - Here is one of many - Don't squish them

Edit: I also should mention that my style is a show/do. I'm trying to balance how much to tell the reader, but not bog them down.

In my next post we can take a look at the disassembler javap and dive in a bit more.

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Re:Hacking Java Bytecode for Programmers (Part 2) by maxbaroi on Friday May 17, 2013 @03:11PM (#5726188)

Thanks for the reply. Look forward to the next post. I guess I prefer to be bogged down, or at least have the ability to go deeper off some tangent and then be able to return to the main lesson.

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