防重复提交（基于AOP+Redis）

防重复提交
客户端可以加Confirm确认框，或者Submit后按钮置灰。
本文介绍服务器防重复（基于AOP+Redis）
引入依赖

		<!-- 引入AOP -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-aop</artifactId>
		</dependency>

		<!-- 引入Redis -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-redis</artifactId>
		</dependency>

自定义注解

/**
 * 防止重复提交注解
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface NoRepeatSubmit {
	/**
	 * 时间周期（秒）
	 */
	int seconds();
	/**
	 * 最大提交次数
	 */
	int maxCount();
}

定义注解的AOP代理

@Aspect
@Component
public class NoRepeatSubmitAspect {
	private Logger logger = LoggerFactory.getLogger(getClass());
	
	@Autowired
	private RedisTemplate redisTemplate;

	/**
	 * 切入点 关联上注解 @NoRepeatSubmit
	 */
	@Pointcut("@annotation(noRepeatSubmit)")
	public void pointcut(NoRepeatSubmit noRepeatSubmit) {
	}

	@Around("pointcut(noRepeatSubmit)")
	public Object around(ProceedingJoinPoint joinPoint, NoRepeatSubmit noRepeatSubmit) throws Throwable {

		ServletRequestAttributes att = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
		HttpServletRequest request = att.getRequest();

		int seconds = noRepeatSubmit.seconds();
		int maxCount = noRepeatSubmit.maxCount();

		// 获取请求 IP
		String ip = request.getRemoteAddr();
		// Redis key = request:ip
		String key = request.getServletPath() + ":" + ip;

		// 获取请求次数
		Integer count = (Integer) this.redisTemplate.opsForValue().get(key);
		if (count == null) {
			count = 0;
		}
		
		this.logger.info("key={}, count={}, seconds={}, maxCount={}", key, count, seconds, maxCount);

		if(count == 0) {
			count++;
			this.redisTemplate.opsForValue().set(key, count, seconds, TimeUnit.SECONDS);
			return joinPoint.proceed();
		} else if (count.intValue() < maxCount) {
			count++;
			this.redisTemplate.opsForValue().set(key, count, 0);
			return joinPoint.proceed();
		}
		return "访问失败";
	}
}

使用注解

	@NoRepeatSubmit(seconds = 5, maxCount = 1)
	@RequestMapping(value = "login", method = RequestMethod.GET)
	public String login(@RequestParam("userName") String userName, String phoneNo) {
		UserVO userVO = new UserVO();
		userVO.setUserName(userName);
		userVO.setPhoneNo(phoneNo);
		LoginEvent userEvent = new LoginEvent(userVO);
		publisher.publishEvent(userEvent);
		return userName + " login success!";
	}

测试结果
5秒内只能访问一次。