How to load a specific set of classes at runtime.

Howdy!
I want to load all the classes in a directory that implement a specific Interface, at runtime. Of course i can load all the classes if i know the String name.
Class t = Class.forName(ruleClass);
     cnst = t.getConstructor( new Class[] { Session.class } );
     try {
         Object obj = cnst.newInstance(new Object[] {
                                          m_fwkSession });
         IRules rule = (IRules)obj;
            ...................where IRule is an interface.
How do i get all the files in that directory and find the classes implementing that interfaces ?

You can either load all the classes and then test if they are assignable from IRule.class (isAssignableFrom())
(you could use a custom classloader if you wanted these classes to be garbage collected)
or
Open the class files and scan them to see if they contain
"myPackage/IRule"
(maybe you would have to parse the .class file, but just scanning it might be good enough)

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Actually, if I try something like this:
new File("think").list()
will return all my .class files located under that
directory.
Is there a question here?No! Thats a statement!
I am telling that under my current directory, there is a another one, filled with .class files containing classes implementing some base Interface. That interface will be used to instantiate the object.
Right ?
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where is the failure ?
:(

How to load a specific set of classes at runtime.

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