Recompile decompiled Java (JD / JAD) source that c

2019-02-17 00:46发布

问题:

(Related question: Java compilers or JVM languages that support goto?)

I have decompiled a jar (Legally, for debugging purposes) and want to recompile it.

I've used both JAD and JD and both don't compile due to goto instructions

E.g.

      goto _L1

      ...
      L1: 
      return true;

Is there an easy way (or any way) to recompile it? (Except to manually refactor and remove the goto's)


回答1:

No, there isn't. In your case, neither JD nor JAD were able to decompile the class files correctly. The 'goto' statements are a hint about the actual program flow.

You could contact the Java Decompiler team directly, send in a class file where decompilation results in illegal source code and ask if it's a bug in the current version or a feature that has not yet been implemented.



回答2:

JAD is a really amazing decompiler, JD ... have some problems with the "try-catch-finally" statements.

Have you try the decompiler of Stiver (http://www.reversed-java.com/fernflower) ?

Emmanuel, author of JD.



回答3:

All decompilers look for code patterns corresponding to Java source constructions and choose the source that fits the best.

Apparently the code you have does not conform to any pattern stored in either JAD or JD so you get uncompilable Java source. This is most likely because JAD has not been actively developed for several years.

I would suggest you look at the Soot project which has a much more aggressive decompiler.

http://www.sable.mcgill.ca/soot/



回答4:

I would recommend a modern decompiler - like CFR or FernFlower!

I put online 6 Java decompilers: Jadx, fast and with Android support, CFR (supports Java 8), JDCore (very fast), Procyon, Fernflower and JAD (very fast, but outdated).

One may use them without installation here: http://www.javadecompilers.com/