public class ManyHandlers extends java.lang.ObjectFrequently many handlers are combined together to handle different aspects of a request. A handler may:
- handle the request and completely generate the response
- partially handle the request, but defer response generation to another handler.
- select another handler to pass the request to.
- use business logic to decide to do one of the above.
HandlerWrapperwhich will nest one handler inside another. In this example, the HelloHandler is nested inside a HandlerWrapper that sets the greeting as a request attribute.
HandlerListwhich will call a collection of handlers until the request is marked as handled. In this example, a list is used to combine the param handler (which only handles the request if there are parameters) and the wrapper handler. Frequently handler lists are terminated with the
DefaultHandler, which will generate a suitable 404 response if the request has not been handled.
HandlerCollectionwhich will call each handler regardless if the request has been handled or not. Typically this is used to always pass a request to the logging handler.
Constructors Constructor Description