Completing the logon action
The skeleton code for the LogonAction class was created from the Web Diagram and is shown in Example | 5-5.
Example 15-5 Skeleton action class (abbreviated)
public class LogonAction extends Action {
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
ActionMessages errors = new ActionMessages();
ActionForward forward = new ActionForward(); // return value
try {
// do something here
} catch (Exception e) {
// Report the error using the appropriate name and ID.
errors.add("name", new ActionMessage("id"));
}
// If a message is required, save the specified key(s)
// into the request for use by the <struts:errors> tag.
.........
}
We have to complete the execute method with our logic. The final code is shown in Example | 5-6. Select Source Æ Organize Imports to resolve the imports.
Example 15-6 Completed execute method of the logon action class
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
ActionMessages errors = new ActionMessages();
ActionForward forward = new ActionForward(); // return value
LogonForm logonForm = (LogonForm)form;
String ssn = logonForm.getSsn();
try {
// Create a bank object with pre-generated in-memory data
Bank bank = ITSOBank.getBank();
Customer customerBean = bank.searchCustomerBySsn(ssn);
// Add the customer to the request object for the JSP pages to use it
request.setAttribute("customer", customerBean);
// Add the bank and ssn objects to the session for further use
request.getSession().setAttribute("ssn", logonForm.getSsn());
request.getSession().setAttribute("ITSOBank", bank);
} catch (InvalidCustomerException e){
errors.add("ssn", new ActionError("error.ssn"));
} catch (Exception e) {
errors.add("error", new ActionError("errors.systemError"));
}
// If a message is required, save the specified key(s)
// into the request for use by the <struts:errors> tag.
if (!errors.isEmpty()) {
saveErrors(request, errors);
// Forward control to the appropriate 'failure' URI (........)
forward = mapping.findForward("failure");
} else {
// Forward control to the appropriate 'success' URI (.......)
forward = mapping.findForward("success");
}
// Finish with
return (forward);
}
Let us now understand some of the action class coding:
| The ActionForm parameter is cast to the correct LogonForm class and the ssn value is extracted. |
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| The customer and accounts are retrieved from the in-memory data autogenerated on invocation to the ITSOBank.getBank() method. |
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| The ssn and bank objects are stored as session data and the customer information is stored in the request block. The session data is available to all actions and JSPs. |
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| If exceptions are thrown by the data access, an ActionMessage is added to the Struts errors list. The error text ("error.ssn" or "errors.systemError") comes from the ApplicationResources file (see Example | 5-1). |
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| An ActionForward of either "failure" or "success" is returned. Struts will find the appropriate resulting action or JSP in the configuration file. |
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