Re: Building classpath at runtime

From:
=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 23 Jan 2007 21:37:30 -0500
Message-ID:
<45b6c664$0$49206$14726298@news.sunsite.dk>
goyald@gmail.com wrote:

I see this question appearing very often in forums but couldn't find a
satisfactory answer. Following is what I am trying achive
1. I have a java application that depends on several classes that are
packaged as jars.
2. Application runs as java -jar "XXX" -cp <classpath>
3. I sometimes need to create emergency fixes or jars. I will like to
put them in an "updates" directory. As names of these jar files will be
determined later, I want my program to scan "updates" directory at
startup, and prepend (before initial classpath) any discovered jar
files.
4. I know that ClassLoader.loadClass() is a viable method but most of
my code takes a new <class>() approach. I will appreciate any
suggestions.


My suggestion would be to:
- put the release jars in lib
- put the patch jars in update
- drop the -cp parameter
- let the main program only create a new URLClassLoader with
   first all jars from update and then all jars from lib
   and then call the real main

Arne

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