Struts 2.ppt

1、July 2008,1,Struts 2,Web Frameworks Comparison JUG Meeting #0002, 8th of July 2008,July 2008,I. Origins and overview,Action based framework MVC2 pattern POJO based,July 2008,II. Basic Architecture,The web browser requests a resource (/mypage.action, etc) The Filter Dispatcher looks at the request an

2、d determines the appropriate Action The Interceptors automatically apply common functionality to the request, like workflow, validation, and file upload handling The Action method executes buisness code, returning a String result The Result renders the output to the browser, be it HTML, images, PDF,

3、 or something else,July 2008,III. Core features,Ognl expression language similar with jsp expression language +type conversions for Maps,Lists primitives not just for Strings +works in other template enviroments velocity,freemarker + calling methods, lambda expressions + projection selecting propert

4、ies from list of objects and creating another temp list (usefull for a select),Results Many result types including jsp,velocity,freemarker, Jasper reports, Xsl,stream,Actions - Instantieted at every request no threading issues - Simple POJOs with any methods for execute() - Not tied with the Servlet

5、 api better testability - Namespace organization,Interceptors Stacking interceptors Many prebuild like Params,FileUpload, ModelDriven,Token,Value Stack - stack of different scopes that is traversed when looking for a value from the view : Temporary obj,Model Object,Action Object,Named Objects(#sessi

6、on), #request,#application,#parameters); - uses Ognl to reffer to scoped properties - resolves properties with same name in different scopes eg. 1.userid,Tag library - based on freeMarker all HTML output produced by tags can be easily customized,July 2008,IV. Comparison criterias,Ajax support Dojo b

7、uilt-in; from version 2.1.0 as a plugin Plugin for JSON s:head theme=“ajax” enables partial submit,validation for forms Many pre-build ajaxed components like tabbedpane,tree,textarea,autocompleter Bookmarkability Has namespaces so bookmarking actions with request parameters is easy SmartURL further

8、enhancements Validation Server side validation in actions with methods or annotations Client validation with xml defined validators many prebuild like email, phone numbers,any regex Ajax validation out of the box with Dojo, can use any xml defined validators,July 2008,IV. Comparison criterias,Testab

9、ility Testing possible by manually instantiating framework objects : Dispatcherand ActionProxy instantiate actions Request and response can be moked with objects like MockServletContextservletContext,MockServletConfig,MockHttpServletRequest,MockHttpServletResponse Execute the desired Method Post and

10、 Redirect Support via redirect-action also possibility to transmit static or dinamic parameters from First action to second Also resovles duplicate posts via Token Session Interceptor blocks subsequent requests until the first request is complete Internationalization Resource boundles for internationalization very customizable at different levels ActionCperties Iperties At package level perties Global resource properties via struts.custom.i18n.resources defined in struts.xml At Ui level , properties fetched with getTe