Struts2 Learning Path (v)--access to web elements

The following is an example of accessing a Web element in the action class, in total four ways. One of the first and third dependent containers, the second and fourth use of IOC thought. The previous two request, session, and application for the map type, followed by two references to the real type HttpServletRequest, Httpservletsession, ServletContext.

1. The first method:

1  Packagecom.user.action;2 3 ImportJava.util.Map;4 5 ImportCom.opensymphony.xwork2.ActionContext;6 ImportCom.opensymphony.xwork2.ActionSupport;7 8  Public classLoginAction1extendsactionsupport{9     PrivateMAP request;Ten     PrivateMap session; One     PrivateMAP Application; A      -      PublicLoginAction1 () { -Request = (map<string, string>) Actioncontext.getcontext (). Get ("Request"); theSession =Actioncontext.getcontext (). getsession (); -Application =Actioncontext.getcontext (). Getapplication (); -     } -      +      PublicString Execute () { -Request.put ("R1", "R1"); +Session.put ("S1", "S1"); AApplication.put ("A1", "A1"); at         returnSUCCESS; -     } -}

2. The second method: (recommended)

1  Packagecom.user.action;2 3 ImportJava.util.Map;4 5 ImportOrg.apache.struts2.interceptor.ApplicationAware;6 ImportOrg.apache.struts2.interceptor.RequestAware;7 ImportOrg.apache.struts2.interceptor.SessionAware; 8 9 ImportCom.opensymphony.xwork2.ActionSupport;Ten  One //The idea of IOC program design A  -  Public classLoginAction2extendsActionsupportImplementsRequestaware,sessionaware,applicationaware { -     PrivateMap<string,object>request; the     PrivateMap<string,object>session; -     PrivateMap<string,object>Application; -      -      PublicString Execute () { +Request.put ("R1", "R1"); -Session.put ("S1", "S1"); +Application.put ("A1", "A1"); A         returnSUCCESS; at     } -      - @Override -      Public voidSetrequest (map<string, object>request) { -          This. Request =request; -     } in      -  to @Override +      Public voidSetsession (map<string, object>session) { -          This. session =session; the          *     } $ Panax Notoginseng @Override -      Public voidSetapplication (map<string, object>application) { the          This. Application =Application; +          A     } the}

3. The third method:

1  Packagecom.user.action;2 3 ImportJavax.servlet.ServletContext;4 Importjavax.servlet.http.HttpServletRequest;5 Importjavax.servlet.http.HttpSession;6 7 ImportOrg.apache.struts2.ServletActionContext;8 9 ImportCom.opensymphony.xwork2.ActionSupport;Ten  One  Public classLoginAction3extendsActionsupport { A     Privatehttpservletrequest request; -     PrivateHttpSession session; -     PrivateServletContext Application; the      -      PublicLoginAction3 () { -Request =servletactioncontext.getrequest (); -Session =request.getsession (); +Application =Session.getservletcontext (); -     } +      PublicString Execute () { ARequest.setattribute ("R1", "R1"); atSession.setattribute ("S1", "S1"); -Application.setattribute ("A1", "A1"); -         returnSUCCESS; -     } -}

4. The fourth method:

1  Packagecom.user.action;2 3 ImportJavax.servlet.ServletContext;4 Importjavax.servlet.http.HttpServletRequest;5 Importjavax.servlet.http.HttpSession;6 7 ImportOrg.apache.struts2.interceptor.ServletRequestAware;8 9 ImportCom.opensymphony.xwork2.ActionSupport;Ten  One  Public classLoginAction4extendsActionsupportImplementsServletrequestaware { A     Privatehttpservletrequest request; -     PrivateHttpSession session; -     PrivateServletContext Application; the      -      PublicString Execute () { -Request.setattribute ("R1", "R1"); -Session.setattribute ("S1", "S1"); +Application.setattribute ("A1", "A1"); -         returnSUCCESS; +     } A      at      Public voidsetservletrequest (HttpServletRequest request) { -          This. Request =request; -          This. session =session; -          This. Application =Application; -     } -}

Struts2 Learning Path (v)--access to web elements