question: public static < T > T assertAndCast ( Class < ? extends T > clazz , Object o ) { assertNotNull ( clazz ) ; assertNotNull ( o ) ; assertTrue ( clazz . isInstance ( o ) ) ; return clazz . cast ( o ) ; }
target:  Given a Type and an object asserts that the object is non-null and an  instance of the specified Type.  The object is then cast to that type and  returned.