Dynamic Class Generation

Q. So what can I do with this?

Here's something I've wanted to do countless times during JSP development:

Map map = ...;
Object bean = BeanCreator.createBeanFromMap(map);
// keys in map are now JavaBeans properties on bean

Of course there's more you can do than that...

Q. OK, so what is it exactly?

This framework creates java classes at runtime from client-supplied information. It's comparable to the Proxy class, but more powerful in two important ways:

Any class can be used as the base of the generated class. Any non-final methods can be selected for overriding.
New methods, not defined elsewhere, can be introduced - that's how Map -> JavaBean translation works.

Methods are dispatched to a client-supplied InvocationHandler interface, similarly to Proxy.

Q. Is there an example somewhere?

Here's a JSP example.

Q. Cool! How can I start using it?

Just get the jar file from the project page and add it to your classpath. You need JDK 1.3 or higher, but no other libraries. The API docs are here. Enjoy!