When I go to C:\Users\(user)\AppData\Roaming\.minecraft\versions\1.6.2, I see my .jar file but when I try to open it, it does nothing. So how do I open my .jar file so I can mod it? I also know that if I extract the files my minecraft crashes. Why is that? How can I open it so I can mod it?

  • How do you open it? Do you double-click it, or right click > Open with > Editor? – 5pike Oct 11 '13 at 6:26
  • 1
    @5pike Not always possible. Most jar files do not have editable code in it, but precompiled one to save you time when compiling your project. Then there is again the difference between access to the jar file's functions and methods and a pure executable jar file. To Raymond Green: I think most people take the byte code which is interpreted by the Java virtual machine and from there on decompile the jar file into somewhat readable code. Problem beeing that classes,variables, etc are not named as in the original code. This is just an educated guess though, so I'm not posting this as an answer. – Strike Oct 11 '13 at 7:25
  • Also, I think this question might be better answered by gamedev.stackexchange.com as it deals with a game-specific programming issue. – Strike Oct 11 '13 at 7:34
  • @strike No, they're not trying to create mods (you can't do that by opening the jar). They're trying to install mods as an end user. – SevenSidedDie Oct 11 '13 at 15:10

you use any package manager that can handle a zip, because a jar is a zip with a different extension, the jar is signed though so you'll need to remove the files in META-INF when you repackage

however I suggest you look at forge; this is an api to make modding easier and allows compatibility between mods

| improve this answer | |
  • 2
    7-zip is a good one. – Dillmo Oct 11 '13 at 13:07
  • @Dillmo Or WinRar. – John May 15 '19 at 9:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.