I wasn't able find any competent disassemblers and reassemblers that were useable from java code as a library. Since I always wanted to do patches in an easily human-readable way, I also added it to the things it can do. This application can be run as a standalone application via CLI (although right now only to patch things) or as a library.

The simplest way to disassemble a class is to convert that class to an Objectweb ASM ClassNode and call the DeltaGenerator#generateBytecode(ClassNode) method. Alternatively you can do it yourself with the BytecodeGeneratorVisitor class.

The easiest way is to invoke the cosntructor of the SLAssembler class. Why the constructor? Because I didn't want to use static and I haven't thought it out all the way when I started creating it.

It uses a custom format to assemble the code into and disassembles the methods and fields via Recaf and stitched together via an in-house application, though reassembly is done manually. Because two different applicaions handle method/field assembly/disassembly there are following limitations:

• Local variables could be remapped in a sub-optimal fashion. This can be negated by using the SKIP_DEBUG flag in your ClassReader. This is done by default in CLI mode.
• Literal strings could have escapes stripped when they shouldn't be or escapeed when not needed. However for normal classes, this is not an issue and is only potent rubbish data are stored as literal strings.
• Annotations are not supported
• Attributes are not supported
• Larger jar size due to shadowing recaf
• Resulting jars may fail the verifier due to missing frames (ASM issue)