@Test
 public void clearClassLoaderForSystemClassLoader() throws Exception {
   BeanUtils.getPropertyDescriptors(ArrayList.class);
   assertTrue(CachedIntrospectionResults.strongClassCache.containsKey(ArrayList.class));
   CachedIntrospectionResults.clearClassLoader(ArrayList.class.getClassLoader());
   assertFalse(CachedIntrospectionResults.strongClassCache.containsKey(ArrayList.class));
 }