Struts 表单验证及业务逻辑验证
1 表单验证
一般判断为空否，实现以JavaScript一样的验证功能（目的是防止JS被禁用时候无法得到预期效果)

public ActionForward execute(ActionMapping mapping, ActionForm form,HttpServletRequest request, HttpServletResponse response) {//接收参数LoginForm loginForm = (LoginForm) form;// TODO Auto-generated method stubSystem.out.println(loginForm.getUserName());String userName = loginForm.getUserName();String password = loginForm.getPassword();//调用后台模型检测用户是否合法UserDao dao = new UserDao();ActionErrors actionErrors = new ActionErrors();if(!dao.validateUser(userName, password)){actionErrors.add("userName", new ActionMessage("error.userNameError"));saveErrors(request, actionErrors);return new ActionForward(mapping.getInput());/*getInput（）获取struts-config.xml Action-mappings里面的input参数*/}//调用后台模型Object [][] userInfo = dao.queryAllUser();request.setAttribute("userInfo", userInfo);//选择转发页面return mapping.findForward("user");}