title: About all kinds of Callback(s) in CGLIB
body: <p>We know that CGLIB provides several Callback implementations, with the most useful one of MethodInterceptor. However, how about other ones(FixedValue, Dispatcher, LazyLoader, NoOp, ProxyRefDispatcher) ? I browse the API document but can not get useful information.  Can anyone show how and when to use these Callbacks in what scenarios ?  I read the related code in Spring but I am still puzzled.</p>
  
  <p>Thanks!</p>