Batch decompiling of Java files with JD-GUI

Question

I'm looking for a program to batch decompile Java classes. I found JAD, but it didn't support some new features of Java, and the benefit of this program is that it can execute from command line and generate a *.java file automatically.

I also found JD-GUI. It supports most features of Java, but the shortcoming is that it can't do batch processing. You need to open the class file with the program and click save.

Is there a way to make JD-GUI do batch processing like JAD?

Answer 1

Command line decompilation for JD-GUI is a highly requested feature but it's not implemented yet. Perhaps you can use the following workaround in the meantime:

1. jar (or zip) all the classes you want decompiled together.
2. Launch JD-GUI and open your jar (zip) archive.
3. Use "File" - "Save JAR Sources" menu option. It will decompile all classes from your archive and save their sources into another zip file.

I haven't seen any good open source JD-GUI alternatives with command-line support, unfortunately, so I think the above is as good as it gets for now.

Answer 2

I could recommend using Jad in conjuction with JadRetro - of course, it can't make Jad produce java generics but the decompiled source (including for Java 1.5+ classes) is functionally equivalent to the original (and back compilable in most cases).
Its use is simple:

jadretro *.class
jad.class

Notes:
1. JadRetro could be used in batch mode like this: jadretro...
2. If you are using jad v1.5.8e (instead of the latest v1.5.8g) then "-c" option should be passed to jadretro (otherwise jad will refuse to decompile Java 1.5+ classes).

Answer 3

It looks like you can launch the GUI with a whole bunch of libs at once using the command line and then CTRL+ALT+s/CTRL+w each tab to quickly save/close. It's not automated but tolerable when decompiling a pile of dependencies. (Note that the "^" is just a trick for doing multi-line commands in Windows.)

"c:\jd-gui-0.3.6.windows\jd-gui.exe" ^
 c:\my-libs\lib-a.jar ^
 c:\my-libs\lib-b.jar ^
 c:\my-libs\lib-c.jar ^
 c:\my-libs\lib-d.jar ^
 c:\my-libs\lib-e.jar

Answer 4

File > Save all sources will save all files in the home directory.

Answer 5

JD-GUI has the ability to batch export class files into.java file, zipped in a jar file.

however, this feature is not controlled by command line, but mouse clicking, this is not stable and sometimes will be stuck.

You can use jd-cli ( https://github.com/kwart/jd-cli/releases/tag/jd-cli-1.2.0 ).

1. prepare your.jar file (containing classes )
2. input: jd-cli target.jar -od jar_result -g ALL

and you will get a zipped java source code file.