Re: Getting a list of Classes in a Package

From:
=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 21 Mar 2007 19:12:11 -0400
Message-ID:
<4601bbc6$0$90276$14726298@news.sunsite.dk>
Omega wrote:

I've been doing some research online about this subject and I've come
across a pretty even balance of "why I need to do it" and "why it
isn't possible".

I want to maybe get some discussion going, and maybe if there is
anyone out there to suggest some alternatives or the best method to
accomplish what I want.

What I've read so far is that:

1. Packages are not hierarchical, and stand separate to each other,
despite similarities.
2. Classes are not fetched until they are requested/needed.

IDEs like NetBeans, Eclipse and others do all kinds of wicked
reflection when you think about it. To what degree they cheat, I
don't know, and would love to!

To put my question or intention as simply as possible:

During run-time, how do I create one instance of each class in a
package when all I know at compile-time is the package's name?


It is impossible to get a list of all classes in a package
(and therefore also to instantiate them).

The absurd but still relevant proof is that I can have
a class on my hard drive belong to the package your are
looking up.

It is possible to get a list of all classes in a dir or
jar file. Actually I have some code for processing a jar
file if you are interested.

Instantiating can become a bit more complex for those
classes without zero argument constructor etc., but
to some extent it is possible.

Arne

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