<form action="${pageContext.request.contextPath }/user/login.action">

 <label>用户名：</label>

 <br>

 <input type="text" name="username">

 <br>

 <label>密码：</label>

 <br>

 <input type="password" name="password">

 <br>

 <input type="submit" value="登陆">

 </form>

 @Controller

     @RequestMapping("/user")

     public class UserController {

 //跳转登陆界面

     @Autowired

     private LoginService loginService;

         @RequestMapping("/toLogin")

         public String toLogin() {

             return "login";

         }

 //登陆操作

         @RequestMapping("login")

         public String login(String username, String password, HttpSession session) {

             //if(username!=null&&!("".equals(username))) {

             // 校验用户登录

             System.out.println(username);

             System.out.println(password);

             // 把用户名放到session中

             session.setAttribute("username", username);

             Map<String, String> parameters = new HashMap<String, String>();

             parameters.put("username", username);

             parameters.put("password", password);

             Login user = this.loginService.selectUserByUsernameAndPassword(parameters);

             if (user != null) {

                 System.out.println("你真他妈的是个人才，竟然猜对了！！");

                 return "redirect:/item/itemList.action";

             } else {

                 System.out.println("去你妈的！账号输错了！！");

                 return "redirect:/user/toLogin.action";

             }

             }

 public interface LoginService {

     Login selectUserByUsernameAndPassword(Map<String, String> parameters);

 }

 @Service

 public class LoginServiceImpl implements LoginService {

     @Autowired

     private LoginMapper loginMapper;

     @Override

     public Login selectUserByUsernameAndPassword(Map<String, String> parameters) {

         // TODO Auto-generated method stub

         return this.loginMapper.findWithLoginAndPassword(parameters);

     }

 }

 Login findWithLoginAndPassword(Map<String, String> parameters);

 <select id="findWithLoginAndPassword" resultMap="BaseResultMap" parameterType="cn.itcast.ssm.pojo.LoginExample" >

     select * from login where username=#{username} and password=#{password}

   </select>

 public class Login {

     private Integer id;

     private String username;

     private String password;

     public Integer getId() {

         return id;

     }

     public void setId(Integer id) {

         this.id = id;

     }

     public String getUsername() {

         return username;

     }

     public void setUsername(String username) {

         this.username = username == null ? null : username.trim();

     }

     public String getPassword() {

         return password;

     }

     public void setPassword(String password) {

         this.password = password == null ? null : password.trim();

     }

 }