MyProxyFactory.java

import javassist.util.proxy.MethodHandler;
import javassist.util.proxy.ProxyFactory;
import org.osgi.framework.Bundle;

public class MyProxyFactory extends ProxyFactory {

    private final Bundle bundle;

    public MyProxyFactory(Bundle bundle) {
        this.bundle = bundle;
    }

    protected ClassLoader getClassLoader0() {
        return new BridgeClassLoader(bundle, getClass().getClassLoader());
    }

    private static class BridgeClassLoader extends ClassLoader {
        private final Bundle delegate;

        private final ClassLoader infra;

        public BridgeClassLoader(Bundle delegate, ClassLoader infraClassLoader) {
            this.delegate = delegate;
            this.infra = infraClassLoader;
        }

        @Override
        public Class<?> loadClass(String name) throws ClassNotFoundException {
            Class<?> loadedClass = null;
            try {
                loadedClass = delegate.loadClass(name);
            } catch (ClassNotFoundException cnfe) {
                loadedClass = infra.loadClass(name);
            }
            return loadedClass;
        }
    }

    public static void test() {
        ProxyFactory f = new MyProxyFactory(getMyBundle());
        f.setSuperclass(Foo.class);
        f.setFilter(new MethodFilter() {
            public boolean isHandled(Method m) {
                // ignore finalize()
                return !m.getName().equals("finalize");
            }
        });
        Class c = f.createClass();
        MethodHandler mi = new MethodHandler() {
            public Object invoke(Object self, Method m, Method proceed,
                                 Object[] args) throws Throwable {
                System.out.println("Name: " + m.getName());
                return proceed.invoke(self, args);  // execute the original method.
            }
        };
        Foo foo = (Foo) c.newInstance();
        ((ProxyObject) foo).setHandler(mi);
    }
}