URLClassLoader classLoader = new URLClassLoader(urls, savedClassLoader);
Thread.currentThread().setContextClassLoader(classLoader);
// recreate resolver since we mess with context class loader
resolver = new DefaultPackageScanClassResolver();
filter.addIncludePattern("a.*.c.*");
resolver.addFilter(filter);
Set<Class<?>> scanned = resolver.findByFilter(filter, "a.b.c");
assertEquals(1, scanned.size());