First, Spring introductionSpringmvcis aSpringa module of the framework,Springmvcand theSpringno need to develop through an intermediate integration layer. Springmvcis a based onMVCof theWebFramework. Spring Web MVCand theStruts2is the framework of the presentation layer.,It isSpringpart of the framework,we can get fromSpring's overall structure:Second, the application of MVC in B/s system1.User initiatedRequestRequest to Controller(Controller)control the data received from user requests and delegate to the model for processing2.controller through Model(Model)process data and get processing resultsthe model usually refers to the business logic3.model processing results returned to the controller4.the controller will model data in the view(View)Show in Webthe model cannot display data directly on the view and needs to be done through the controller. If theC/Sin-app models are the data that can be displayed in a view. 5.controller will viewResponseResponding to users show the data to the user or process the results through a view. Three, spring working principle
(1).initiating a request to the front-end controller(Dispatcherservlet);(2).front-end controller requesthandlermappingFindHandler, can be based onXMLconfiguration, annotation to find;(3).Processor Mapperhandlermappingback to Front controllerHandler;(4).The front controller invokes the processor adapter to performHandler;(5).Processor adapter to performHandler;(6). Handlerexecution finishes to adapter returnModelandview;(7).the processor adapter returns to the front-end controllerModelandview (is aSpringmvcone of the underlying objects of the framework, includingModeland theView);(8).The Front controller requests the view resolver to parse the view, resolving the real view based on the logical view name(JSP ...);(9).The view resolver returns to the front-end controllerView;(Ten).front-end controller for view rendering, view rendering is the model data(in theModelandviewobject in)Fill toRequestthe domain. (one).the front controller responds to the user's results.
Iv. Introduction of Components
1
, front-end controller
Dispatcherservlet
(No siege lion development required), provided by the frameworkfunction: Receive request, response result, equivalent to transponder, CPU. With theDispatcherservletthe coupling between the other components is reduced. a user request arrives at the front controller, which is equivalent toMVCin the patternC,Dispatcherservletis the center of the entire process control, which calls other components to process the user's request,Dispatcherservletthe presence of a component reduces the coupling between components.
2
, processor mapper
handlermapping (
no need for siege lion development
),
provided by the frameworkfunction: According to the requestedURLFindHandler handlermappingresponsible for the user request to findHandlerthat is, the processor,SpringmvcDifferent Mapper is provided to implement different mapping methods, such as: Configuration file mode, interface mode, annotation method and so on.
3
, processor Adapter
Handleradapterrole: According to specific rules (Handleradapterrequired rules) to executeHandler throughHandleradapterexecution of the processor, which is an application of the adapter pattern, can be performed on more types of processors through the extension adapter.
4
, Processor
Handler (
need to develop siege Lions
)
Note: Write
Handler
When you follow
Handleradapter
required to do so the adapter can go to the correct execution
HandlerHandleris the followingDispatcherservletthe back-end controller of the front -end controllerDispatcherservletunder the controlHandlerprocessing of specific user requests. becauseHandlerrelated to specific user business requests, so the general situation requires the siege lion to develop according to business requirementsHandler.
5
, view resolver
View Resolver (
no need for siege lion development
),
provided by the frameworkfunction: Perform a view resolution that resolves to a real view based on the logical view name (View) View Resolverresponsible for generating the processing resultsViewView,View ResolverFirst, the logical view name is parsed into the physical view name that is the specific page address, and then the generatedViewView object, and finally theViewrendering renders the processing results to the user through the page. SpringmvcThe framework provides a lot ofViewview types, including:Jstlview,Freemarkerview,Pdfviewand so on. In General, the model data needs to be presented to the user through page labels or page template technology, and the specific page needs to be developed by the siege Lion according to the business requirements. 6
, Views
View (
need to develop siege Lions
jsp ...
) Viewis an interface that implements classes that support differentViewType (JSP,Freemarker,PDF ...)
VC in B/s system should be two, MVC in the B/S system Application
How the SPRINGMVC works
