Anti-Patterns:

Concern Slush

Different tiers (presentation, business, and data logic) are not clearly separated.

Tier Leakage:

A tier is allowed to access another tier not immediately adjacent to it.

Hardwiring

Need to search through all source code to change a link or change application workflow.

Validation Confusing

Tight-Skin

Data Madness

Setting up for Struts

1. In JSP page, include Struts tag library struts-form.tld, create prefix
2. Set action to *.do
3. Set properties for actions
4. Properties will be picked up by ActionForm derived class

MVC Model

• org.apache.struts.action.ActionServlet is set to be the default servlet. URL pattern mapped to servlet is usually *.do. Mapping is done in web.xml.
• Set main configuration file, typically struts-config.xml, in param-name property config for the servlet.
• Main configuration file contains all form-beans and action-mappings.
• Action derived classes call ActionMapping.findForward to redirect page.
• The servlet, ActionServlet, acts as the controller, taking user request and maps it to an action mapping

Sequence of events

• index.jsp is called, page forwards to Welcome.do
• Welcome.do is a virtual, and struts-config.xml maps it to welcomeStruts.jsp

• index.jsp is called, page contains action login.do, which maps to /login, loginForm, and struts.LoginAction
• loginForm is a Form Bean, which maps to struts.LoginForm
• LoginForm is a POJO providing a backing object to the form properties
• LoginAction derives from Action. It contains the logic that determines whether the forward page will be “success” or “failure”
• “success” and “failure” are properties of LoginAction mapping to htmls.