Jar md5 changes every build

Well I wanted to check a downaloded version of my game with md5,

however if i have the same content and when rebuilding the md5 changes

But the jm3 stuff build with the build.xml does not change, why?

The file has metadata like last modified etc. isnt that added to the md5 info? How do you generate it anyway? What do you mean by build.xml stuff? A jMP project? If you dont “clean and build” I think it just updates the files necessary…

Hm I mean the antfile in the jme3 svn, it seems to not change the md5 if the source is the same, while mine changes it. I already found the reasons, 1. timestamps of .class files, and content/creationtime of manifest.

I still wonder however why the jme build script does not have the same behaviour. I already looked through it but I cannot find the reason.

The question would rather have to be why does your project/IDE change the files?

Well I have a buildpath where i let my own ant script compile the lcass fiels to, then i let it package as jar, after everything is complete I clean the folder