Any maintained Open-Source Java Decompiler ?

Question

Is there any maintained Open-Source Java Decompiler?

• Dava seems to be a thesis project rather than a programming tool.
• JReversePro shows signs of activity but has had no release since 2002
• JODE has had no release since 2004
• dcompiler has had no release since 2002
• javap only shows assembly-level code
• Soot is not really a decompiler
• Fernflower is maintained but not open source (yet?)
• Java Decompiler (JD) is not open source
• DJ Java Decompiler is not open source
• Cavaj is not open source
• jad is not open source, and it is dead

Answer 1

http://java.decompiler.free.fr/

it supports Java5

Answer 2

Would jode not be appropriate because even though there hasn't been a release since 2004, what language features have been added since then that wouldn't be able to be decompiled?

Looking on wikipedia, as long as the Java 5 features (generics, annotations et al) are supported, I don't think the class file format has have changed since then.

Hope this helps (although I am fully aware that I have answered a question with a question!)

Answer 3

You can try to contact the author of http://www.reversed-java.com/fernflower/

It is an analytical decompiler and a very good one. The author wanted to release the code under a GPL compliant license in the near future, so if you ask him, probably he will release it. Latest news on the website are from August 2009.

Answer 4

Hi Nicolas,

what do you need the source code for? Unfortunately I can't release it under GPL right now, because there are still some legal questions to be solved. However if you are representing a well established company or an R&D institute, an exception would be possible.

As for the current project status: over the last months I have completely rewritten the core of the decompiler, along with fixing quite a lot of bugs and improved performance. I hope to release a binary stand-alone version in the next time, provided my other projects won't monopolize me.

P.S. Sorry, the above refers to Fernflower of course. I'm the author of it.

Answer 5

Hello Stiver

I am a big fan of your work but your site seems to be down, I hope this isn't more than an upgrade or system maintenance. I think your site need to be preserved let me know if I can help with server space, processor power, etc.

Answer 6

Depending on your goals, look into soot. Soot provides Java decompilers that breaks Java down into an intermediate language closer to the byte code level. The advantage is that you can always modify and recompile versus many of the other decompilers that don't always generate compilable code.