SpringBoot实现token登录的示例代码

package com.qcby.util;
 
import com.qcby.entity.User;
 
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;
 
public class TokenUtil {
    /**
     * 创建map用于存储所有的令牌
     *
     * token  -  User
     */
    private static Map<String, User> tokenMap=new HashMap<>();
 
    /**
     * 生成token，存储token-user对应关系
     * 返回token令牌
     * @param user
     * @return
     */
    public static String generateToken(User user){
        //生成唯一不重复的字符串
        String token = UUID.randomUUID().toString();
        tokenMap.put(token,user);
        return token;
    }
 
    /**
     * 验证token是否合法
     * @param token
     * @return
     */
    public static boolean verify(String token){
        return tokenMap.containsKey(token);
    }
 
    /**
     * 根据token获取用户信息
     * @param token
     * @return
     */
    public static User getUser(String token){
        return tokenMap.get(token);
    }
}

package com.qcby.interceptor;
 
import com.qcby.util.TokenUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
 
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
 
public class LoginInterceptor  implements HandlerInterceptor {
 
   
    //Controller逻辑执行之前
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("preHandle....");
        String uri = request.getRequestURI();
        System.out.println("当前路径"+uri);
 
        /**
         * HandlerMethod=>Controller中标注@RequestMapping的方法
         *  需要配置静态资源不拦截时，添加这块逻辑  => 前后端分离项目
         */
        if (!(handler instanceof HandlerMethod)) {
            return true;
        }
 
        String token=request.getHeader("qcby-token");
 
        if (!TokenUtil.verify(token)) {
            // 未登录跳转到登录界面
            throw  new RuntimeException("no login!");
        } else {
            return true;
        }
    }
 
    //Controller逻辑执行完毕但是视图解析器还未进行解析之前
    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle....");
    }
 
    //Controller逻辑和视图解析器执行完毕
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("afterCompletion....");
    }
}

@RestController
@RequestMapping("user")
public class UserController { 
    @Autowired
    private UserService userService;
    @ApiOperation("用户登录接口")
    @RequestMapping(value="login",method = {RequestMethod.GET,RequestMethod.POST})
    public Map<String,Object>login(User user){
        Map<String,Object> map=new HashMap<>();
        map.put("code",0);
        if(StringUtils.isEmpty(user.getUsername())||StringUtils.isEmpty(user.getPassword())){
            map.put("msg","用户或密码为空！");
            return map;
        }
        QueryWrapper<User> queryWrapper=new QueryWrapper<>();
        queryWrapper.eq("username",user.getUsername())
                .eq("password",user.getPassword());
        User user1=userService.getOne(queryWrapper);
        if(user1!=null){
 
            String token= TokenUtil.generateToken(user1);
            map.put("cod",1);
            map.put("data",user1);
            map.put("token",token);
        }else {
            map.put("msg","用户名或密码错误!");
        }
        return map;
    }
}