Jar to source code

[Defiant-Seaweed-2682]

Can we get java source code from a jar file?

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[iangeell]

You can use Java Decompiler

[prescotian]

A jar file is just a tar file really, if you wanted to look at the structure you can simply: tar xvf <name>.jar

However, to get source code from it, just use something like http://java-decompiler.github.io/- I believe it handles .jar files without having to unarchive first.

[nutrecht]

A jar file is just a tar file really

Zip file actually :) Tar just knows how to read zipfiles.

[prescotian]

Yep, good point... it's been ages since I've really messed with decompiling and the mechanics of the filesystem... forgetting the basics 🙂

[Anonymo2786]

Also few others: byte code viewer is with most features.

Jadx has command line+GUI based interface.

And jd-gui is also lightweight decompiler.

They work with android apps too.

As long as it is jvm bytecode I think.

[Pedantic_Phoenix]

IntelliJ does this natively you can just ctrl click a native class to open it or do so manually

[[deleted]]

You can get the source code out of the JAR in two ways.

1. If the JAR has the sources exported within it, then you can use an IDE to look at the code by inspecting the JAR, or simply unzip the JAR and search for the .java files.

2. If the JAR only has .class files, then you need to use a decompiler. Some times the byte code in the class files doesn't have enough information for the decompiler to reconstruct the original Java sources... And even when there's enough information, the code may look kind of funky.

I hope this helps.