利用公共的Action實現用戶合法性的校驗

  在這里,我們可以通過實現一個公共的Action并增加相應的權限驗證功能來實現用戶權限的校驗工作.
這樣,在進行業務功能開發的時候,所有需要執行權限校驗的Action都需要繼承自此公共的Action.
下面是一個簡單的例子
具有校驗功能的Action(SecureAction.java)
/*
 * Generated by MyEclipse Struts
 * Template path: templates/java/JavaClass.vtl
 */
package dgut.ke.struts.secure;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

/**
 * MyEclipse Struts
 * Creation date: 08-28-2007
 *
 * XDoclet definition:
 * @struts.action validate="true"
 */
public abstract class SecureAction extends Action {
 /*
  * Generated Methods
  */

 /**
  * Method execute
  * @param mapping
  * @param form
  * @param request
  * @param response
  * @return ActionForward
  */
 public final ActionForward execute(ActionMapping mapping, ActionForm form,
   HttpServletRequest request, HttpServletResponse response)throws Exception {
  HttpSession session = request.getSession();
  String userId = (String)session.getAttribute("SESSION.USER");
  if(userId==null)
   return (mapping.findForward("isNullSession"));
  else
   return doExecute(mapping,form,request,response);
 }
 
 public abstract ActionForward doExecute(ActionMapping mapping,
             ActionForm form,
             HttpServletRequest request,
             HttpServletResponse response)
 throws Exception;
    
}
下面編寫一個普通的Action(isNullSessionAction.java)繼承自此公共Action
/*
 * Generated by MyEclipse Struts
 * Template path: templates/java/JavaClass.vtl
 */
package dgut.ke.struts.secure;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

public class IsNullSessionAction extends SecureAction {

 @Override
 /*重寫類中的方法*/
 public ActionForward doExecute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {
  //通過父類的權限驗證則該方法會被執行
  return mapping.findForward("success");
 }
}
struts-config.xml中的相關配置
  <action path="/isNullSession" type="dgut.ke.struts.secure.IsNullSessionAction">
     <forward name="success" path="/success.jsp"></forward>
     <forward name="isNullSession" path="/index.jsp"></forward>
  </action>
  <action path="/secureAction" type="dgut.ke.struts.secure.SecureActionAction"/>