proguard-core VS bytecode-viewer

Anyways, have you looked at Proguard core?

For generating Java bytecode/class files you could take a look at ProGuardCORE . It's a bytecode manipulation and analysis library that grew out of ProGuard.

The MethodBuilder "low-level" example looks like the ProGuardCORE API for building classes & code sequences, which can be written as:

Something else that could make your code generation for your JVM language easier: ProGuardCORE (https://github.com/Guardsquare/proguard-core). It can be used to read, generate and analyse Java bytecode.

Some examples for code generation: ProGuard where the project originated (https://github.com/Guardsquare/proguard), Brainf*ck compiler (https://github.com/mrjameshamilton/bf), Lox compiler (https://github.com/mrjameshamilton/klox)

Disclaimer: I work at Guardsquare on ProGuardCORE so may be biased ;)

I implemented Lox in Kotlin based on the book's Java interpreter then added a JVM backend using ProGuardCORE: https://github.com/mrjameshamilton/klox

You can find out more about ProGuardCORE on GitHub and the manual contains some further examples.

Not a book or guide but a useful library for working with/generating JVM class files is ProGuardCORE. It's the underlying library used by ProGuard and I also recently used it to add a JVM backend to my implementation of Lox from the Crafting Interpreters book.

After completing the first part of the book (using Kotlin instead of Java), I added a JVM backend using ProGuardCORE (https://github.com/Guardsquare/proguard-core).

The biggest difference is our initial goal of creating a tool for application developers rather than a security team. This means we aim to exclude information that the application developer definitely knows and doesn't want to see again, e.g. the list of permissions an application is requesting. Furthermore we try to focus on nice and intuitive UX that is familiar to this audience, enabling an application developer to be very efficient in reading & interpreting the results (e.g. easy comparison of two builds). Also note that this is built on the same core technology as ProGuard. This foundation of compiler components (e.g. our partial evaluator) and the knowledge and experience at Guardsquare that comes with it will unlock many more in-depth code checks.

I think they forgot to google translate the disadvantages of JEB Decompiler

I haven't used JEB to comment, but I've gotten a lot of mileage out of https://github.com/pxb1988/dex2jar#readme and then feed the normal Java jars it produces into https://github.com/mstrobel/procyon#readme and (of course) one shouldn't overlook picking your favorite tool for dealing with AndroidManifest.xml which often has fun things hiding in it

While digging up those links, I was reminded that some folks enjoy https://github.com/Konloch/bytecode-viewer#is-there-a-demo because it can be easier to "try out" a few of the decompilation engines, but I don't use it because it's hard to do batch things with it, versus dex2jar into procyon is automation friendly

Here's a good tool for inspecting the bytecode of applications, with built in decompiler support: https://github.com/Konloch/bytecode-viewer

If you're curious what anything (Lombok or otherwise) compiles to, JVM bytecode is much simpler than the kinds C/C++ compiles to. It's fairly readable even with the JDK disassembler javap. There are also various community disassemblers and decompilers that provide nicer output than javap. I use https://github.com/Konloch/bytecode-viewer, which is a GUI frontend for several. If one decompiler doesn't handle a class well, another usually does.

I use Bytecode Viewer, https://github.com/Konloch/bytecode-viewer with Dark Mode.

if you do use this plugin i'd recommend also using https://bytecodeviewer.com/ to check the supposed malicious lines of code.

Take a look at tools like this one to get an idea of what you can actually get: https://bytecodeviewer.com/

Also, you can always install the latest release and then put it through a Java decompiler to get the complete source code. It might have some errors since decompilers aren't perfect, but will give you a more complete source code than anything I can legally provide.