jsp验证码

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@page import="entity.UserInfo"%>
<%@page import="dao.UserInfoDao"%>
<%
//获取表单内容
String validCode = request.getParameter("validCode");
String sValidCode = (String) session.getAttribute("validCode");
if (validCode.equals(sValidCode)) {
String loginName = request.getParameter("loginName");
String loginPwd = request.getParameter("loginPwd");

UserInfo userInfo = UserInfoDao.instance().Login(loginName,loginPwd);

if (userInfo != null) {
if (loginName.equals(userInfo.getLoginName())) {
session.setAttribute("login",userInfo);
response.sendRedirect("manager.jsp");
} else {
out.print("登录失败！");
}
} else {
out.print("登录失败！");
}
} else {
out.print("验证码失败！");
}
%>