Re: setting up CLASS PATH dynamically

From:
=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>
Newsgroups:
comp.lang.java.programmer
Date:
Sun, 30 Mar 2008 17:19:56 -0400
Message-ID:
<47f003f8$0$90273$14726298@news.sunsite.dk>
strus_82 wrote:

I'm trying to write my ClassLoader but I have the following problem:
when I read all data from .class (here it is CustomClassLoader.class)
file to byte array - I call defineClass() but an exception is thrown:
"d:/examples/temp/CustomClassLoader (wrong name: CustomClassLoader)".

I think I pass wrong first parameter to defineClass(String name,
byte[] b, int off, int len). The CustomClassLoader.class file is
located in d:\examples\temp\.

I have also tried to use findClass() but it's the same.

I have tried different combination of the path to that .class file but
the result is the same all the time :/

Could You give me some hint? All I want to do (for couple hours :/) is
to load class from some path of the local file system (but the path is
not set in CLASS PATH).


It is much simpler than that !

URLClassLoader cl = new URLClassLoader("file:/d:/examples/temp/");
Object o = Class.forName("mypackage.MyClass", true, cl).newInstance();

will load mypackage.MyClass from D:\examples\temp\mypackage\MyClass.class !

Arne

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