Springboot：员工管理之登录、拦截器（十（4））

1：构建登录javaBean

com\springboot\vo\LoginUser.java

package com.springboot.vo;
import lombok.Data;

@Data
public class LoginUser {
    //登录用户名
    private String username;

    //登录密码
    private String password;
}

2：构建登录controller

com\springboot\controller\LoginController.java

package com.springboot.controller;

import com.springboot.vo.LoginUser;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.PostMapping;
import javax.servlet.http.HttpSession;

@Controller
public class LoginController {

    @PostMapping("/login.html")
    public String login(LoginUser user, Model model, HttpSession session){

        //如果用户名不为空且密码等于123456 登录成功
        if(!StringUtils.isEmpty(user.getUsername())&&"123456".equals(user.getPassword())){

            //登录成功后把用户名放到session中用于登录拦截验证
            session.setAttribute("loginUser",user.getUsername());

            //main.html请求定义在自定义的视图解析器中
            //重定向的意义在于让浏览器的URL路径更加真实
            return "redirect:/main.html";
        }else {
            // 用于登录界面回显错误信息
            model.addAttribute("msg","用户名或者密码错误");
            return "index";
        }
    }
}

3：构建登录拦截器

package com.springboot.config;

import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/*登录拦截器*/
public class LoginHandlerInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, 
                             HttpServletResponse response, 
                             Object handler) throws Exception {

        //从session中获取用户名
        String username = (String)request.getSession().getAttribute("loginUser");
        //如果用户名为空则不放行
        if(StringUtils.isEmpty(username)){
            //登录界面回显的错误信息
            request.setAttribute("msg","请先登录");
            //转发到登录页
            request.getRequestDispatcher("/index.html").forward(request,response);
            //不放行
            return false;
        }
        //放行
        return true;
    }
}

4：把登录拦截器添加到spring以及添加主页视图解析器

package com.springboot.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration //配置类注解
public class MyConfig implements WebMvcConfigurer {
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        /*访问首页视图解析器*/
        registry.addViewController("/").setViewName("index");
        registry.addViewController("/index.html").setViewName("index");
        /*访问主页视图解析器*/
        registry.addViewController("main.html").setViewName("dashboard");
    }

    //把国际化配置加入到容器中，使其生效
    @Bean
    public LocaleResolver localeResolver(){
        return new MyLocaleResolver();
    }

    //登录拦截器
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new LoginHandlerInterceptor()).
                //拦截所有请求
                addPathPatterns("/**").
                //排除以下请求不拦截
                excludePathPatterns("/","/index.html","/login.html",
                                    "/css/**","/js/**","/img/**");
    }
}

5：改造index.html

6：测试

输入错误的用户名、密码：

直接访问主页：http://localhost/main.html

输入正确的用户名、密码：