MANIFEST.MF

I imported a java project from someone. It contains a "META-INF/MANIFEST.MF" file already.

Now I am creating my own jar file for this project. When I use ant to create a jar for this project, should I copy this MANIFEST.MF that is already in my java project ? Or should I let jar utility create its own MANIFEST.MF ?

I just don't know how I can copy the existing MANIFEST.MF into the new jar ? It seems jar utility automatically creates one everytime you jar it, right ?

You do not necessarily need a manifest. Desktop apps have one in order to provide "double-clickability", but if the jar file contains a library for use by other code then there's probably no need.

And no, the jar tool does not automatically create a manifest.

See http://faq.javaranch.com/java/JarFiles for links to more information.

Thanks. Currently in the eclipse project I imported, it has a "META-INF/MANIFEST.MF". So if I just want to use this existing one for my jar, I just need to copy this META-INF/MANIFEST.MF to "build" directory along with the compiled ".class" file, then jar everything under the "build", that's it. Since the jar utility in ant does not auto overwrite the MANIFEST it will be kept.

Does it sound OK ?