[Kaffe] does anyone care about this jar feature?

Alex Nicolaou anicolao at mud.cgl.uwaterloo.ca
Wed Feb 10 19:03:57 PST 1999

Moses DeJong wrote:
> To be perfectly honest, I do not think this is a feature that
> anyone should be using and I would rather not add it to my
> implementation because it causes a number of other "problems".
> Does anyone think that this feature is worth adding? If you
> can think of some good reason why this might be a good feature
> to have please post it to the list so I know where you stand.
> Please, no "that is how Sun does it" posts.

But *that is how Sun does it* ;-) (Kidding! Kidding! Sheesh.)

This feature is usually used to copy directory trees with tar; jar is
clearly meant to operate the same way tar does. Is this useful? I don't
really know...typical usage that I have for this feature are to extract
jars to a different directory:

# this command will stick an unpacked version of activation.jar in
cat activation.jar | (cd /tmp/activ; jar xv)

Using rsh, you could also be unjarring the file to a different machine,
but I've never bothered with that. Normally I want to look at some
.class file temporarily, so I just unpack somewhere where I can later
destroy the unpacked object files.

With tar, you'd often do something like:

# you wish this would preserve symlinks
jar cv * | (cd ../ac; jar xv)

to recursive copy a directory and its symlinks. However jar does not
preserve symlinks, and it also introduces extra files, so this form is
not very useful.

Other than the use of unpacking to a different directory (which is very
convenient if you're used to doing it that way) I don't have a use for
the feature.

The real question that comes to mind is why is it a problem to handle
writing to standard in/out?


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