SpringBoot开发（3）——拦截器

package com.cxsbg.interceptor;

import com.cxsbg.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Component //注入
//实现登录拦截器，验证token是否有效，如果有效就放行
public class LoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //获取请求头中的token
        String token = request.getHeader("token");
        //判断token是否为空，如果为空，说明未登录，不放行
        if(!StringUtils.hasText(token)){
            //发送错误码
            response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
            return false;
        }
        //判断token是否有效，如果无效，不放行
        try {
            Claims claims = JwtUtil.parseJWT(token);
            String subject = claims.getSubject();
            System.out.println(subject);
        }catch (Exception e){
            //发送错误码
            response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
            return false;
        }
        return true;
    }
}

import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration //注入
public class LoginConfig implements WebMvcConfigurer{

    @Autowired
    private LoginInterceptor loginInterceptor;
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //首先添加拦截器
        //添加拦截路径
        //排除拦截路径
        registry.addInterceptor(loginInterceptor)//添加拦截器
                .addPathPatterns("/**")//拦截任意路径
                .excludePathPatterns("/sys_user/login");//排除登录路径
    }
}