using java decompiler jd-gui and getting // INTERNAL ERROR //

Question

I decompiled an apk file using dex2jar and opened the resulting jar file in jd-gui. I can view almost all of the code nicely but one section - the constants - displays only // INTERNAL ERROR // and nothing else. Is there a way to retrieve the constants?

Solution 1

Anyone passing by this question should look at this instead: https://github.com/deathmarine/Luyten

Using this instead of jd-gui, I was able to successully view all code which showed as INTERNAL ERROR on jd-gui.

You can also try Jadx: https://github.com/skylot/jadx

Solution 2

I fixed the problem by installing Java Jdk 64Bit "Java SE Development Kit 8u111"

Comments

[Tomáš Zato]

Luyten doesn't allow to open directory (eg. several .class files in directory structure). It only works in jar files, therefore not useful to me.

[James Watkins]

@TomášZato you can build a jar file yourself. Just put the whole directory structure into a zip file and rename it to jar.

[Xelian]

OK but jd-gui can decompile wars and the libs in it are linked. In Luyten if we put all the jar content in zip and rename to jar then we can see the classes but the jars in the lib can not be decompiled.

[E. Sundin]

Jadx works very well. Luyten didn't display the lambda classes which was viewable in Jadx and somewhat in JD-GUI.

[sam]

luyten doesn't have a type search (ctrl+T) which is essential And jadx didn't decompile just showed a node with Source Code and nothing more

[Scott Chu]

They both display unicode character(in my case, Chinese) as \uxxxx but I want to see the real character. jd-gui doesn't has this problem. By the way, When I use jd-gui 1.4, it has this "internal error" problem but when I switch back to o.3.6 it works well. Does anyone know why? (note: I'm using Win7 64bit)

[Phani]

Mostly, it works well unless there is some java version issue.

[Peter]

JD-GUI wasn't able to handle files of mine that had a large range of FX bindings and lambdas - Luyten was the way to go

[e_v_e]

I downloaded the jar directly from github.com/deathmarine/Luyten/releases and it works like a charm! Thanks!!

[happybuddha]

I think Luyten has a shortcoming. I tried opening a war file and in its tiny taskbar it says File is too large : 76.5 MB

[yetAnotherCoder]

Luyten worked like a charm! JD-GUI could not do it for me. Big upvote!

[Imdad]

Please put some effort to explain your answer. That would really help others who are troubleshooting similar problems