Re: Force loading of derived classes?

From:
Patricia Shanahan <pats@acm.org>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 27 Jul 2006 21:41:35 GMT
Message-ID:
<jqayg.6145$157.2911@newsread3.news.pas.earthlink.net>
A. W. Dunstan wrote:

Patricia Shanahan wrote:

A. W. Dunstan wrote:

I'm developing an application where the user selects an algorithm named
in a drop-down list, optionally sets parameters, then presses "go". We
then do stuff with the results of running the algorithm, but that has
no bearing on my question.

Each algorithm is embodied in a class, where each of these classes is
derived from an abstract base class. At present, the GUI drop-down
list knows about all available algorithms at compile time, which seems
ugly.

In addition to whatever you decide to do about automatically discovering
classes, would it make sense to change the GUI to allow a typed-in
algorithm name? Do your users extend the program by adding algorithms,
or only choose from the ones you supply?

Patricia


Only ones we supply. Each algorithm will have it's own set of parameters
which they can fiddle with, tho'. I've currently got things set up so each
algorithm provides a JPanel with suitable editing fields; one algorithm has
no parameters, the rest have some parameters in common, but not all. When
you select the algorithm, the appropriate JPanel is displayed.


In that case, you have a lot of control. Put the key classes in a
package of their own, and as part of your "make" process search the
corresponding directory for .java files.

Patricia

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