我们需要根据IP去限制用户单位时间的访问次数，防止刷手机验证码,屏蔽注册机等，使用注解就非常灵活了

1 定义注解

@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.METHOD)@Documented //最高优先级@Order(Ordered.HIGHEST_PRECEDENCE)public @interface RequestLimit {    /**     *      * 允许访问的次数，默认值MAX_VALUE     */    int count() default Integer.MAX_VALUE;    /**     *      * 时间段，单位为毫秒，默认值一分钟     */    long time() default 60000;}

 2 实现注解

@Aspect@Componentpublic class RequestLimitContract {    private static final Logger logger = LoggerFactory.getLogger("RequestLimitLogger");    @Autowired    private RedisTemplate
     
       redisTemplate;    @Before("within(@org.springframework.stereotype.Controller *) && @annotation(limit)")    public void requestLimit(final JoinPoint joinPoint, RequestLimit limit) throws RequestLimitException {
          try {            Object[] args = joinPoint.getArgs();            HttpServletRequest request = null;            for (int i = 0; i < args.length; i++) {                if (args[i] instanceof HttpServletRequest) {                    request = (HttpServletRequest) args[i];                    break;                }            }            if (request == null) {                throw new RequestLimitException("方法中缺失HttpServletRequest参数");            }            String ip = HttpRequestUtil.getIpAddr(request);            String url = request.getRequestURL().toString();            String key = "req_limit_".concat(url).concat(ip);            long count = redisTemplate.opsForValue().increment(key, 1);            if (count == 1) {                redisTemplate.expire(key, limit.time(), TimeUnit.MILLISECONDS);            }            if (count > limit.count()) {                logger.info("用户IP[" + ip + "]访问地址[" + url + "]超过了限定的次数[" + limit.count() + "]");                throw new RequestLimitException();            }        } catch (RequestLimitException e) {            throw e;        } catch (Exception e) {            logger.error("发生异常: ", e);        }    }}
     

3 自定义Exception

public class RequestLimitException extends Exception {    private static final long serialVersionUID = 1364225358754654702L;    public RequestLimitException() {        super("HTTP请求超出设定的限制");    }    public RequestLimitException(String message) {        super(message);    }}

4 在Controller中使用

@RequestLimit(count=100,time=60000)@RequestMapping("/test")public String test(HttpServletRequest request, ModelMap modelMap) {    //TODO }

 我使用了redis缓存访问次数,并且设置自增1，其实用静态map也可以。