一、拦截器

代码如下。

基本的思路是，定义一个表示需要校验的注解，然后在拦截器中抓取。

值得注意的是：

假如验证不通过，并不是简单地抛出异常，而是向 response 中写入返回以Json 字符串表征的结果。

1） 定义注解@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.METHOD)public @interface Authority {}2） 定义拦截器@Slf4jpublic class IpPermissionInterceptor extends HandlerInterceptorAdapter {    @Autowired    private AuthenticService authenticService;    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        log.info("提示：请求进入了拦截器");        if (!(handler instanceof HandlerMethod)) {            return true;        }        final HandlerMethod handlerMethod = (HandlerMethod) handler;        Authority authority = handlerMethod.getMethodAnnotation(Authority.class);        if (Objects.isNull(authority)) {            return true;        }        log.info("提示：打印访问ip,x-real-ip:{},x-forwarded-ford:{}",request.getHeader("x-real-ip"),request.getHeader("x-forwarded-for") );        String ip = getIp(request);        log.warn("提示：请求方的IP {}", ip);        if (StringUtils.isNotBlank(ip)) {            ResultDTO
   
     resultDTO = authenticService.authenticate(ip);            if (resultDTO.isSuccess()) {                log.info("提示：验证IP通过");                return true;            }        }        ResultDTO failResultDTO = ResultDTO.fail(null, "提示：：IP不受信，请联系管理员");        try {         // 向 reponse 中写入结果            response.setCharacterEncoding("UTF-8");            response.setContentType("application/json; charset=utf-8");            response.getWriter().append(JSON.toJSONString(failResultDTO));        } catch (IOException e) {            log.warn("提示：：验证IP失败", e);            response.sendError(HttpStatus.BAD_REQUEST.value());        }        return false;    } // 获取IP    private String getIp(HttpServletRequest request) {        String realIp = request.getHeader("x-real-ip");        if (StringUtils.isNotBlank(realIp)) {            return realIp;        }        String forwardedIPs = request.getHeader("x-forwarded-for");        if (StringUtils.isNotBlank(forwardedIPs)) {            String[] split = StringUtils.split(forwardedIPs, ",");            return split[0];        }        return request.getRemoteAddr();    }}3） 向 Spring 容器注册本拦截器