黑名单过滤器，启动一个线程定时同步远程redis黑名单数据至本地JVM内存；

BlackFilterAspect.java

package com.jd.couponservice.service.aspect;

import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javax.annotation.Resource;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.stereotype.Component;

import com.alibaba.dubbo.common.utils.NamedThreadFactory;
import com.jd.couponservice.client.dict.CouponResultCodeDict;
import com.jd.couponservice.client.domain.coupon.CouponResult;
import com.jd.couponservice.client.domain.coupon.CouponSopResult;
import com.jd.data.redis.RedisUtils;

/**
 * 黑名单过滤器
 * 
 * @author YANGLiiN
 * @date 13-6-17 上午11:28
 */

@Aspect
@Component
public class BlackFilterAspect implements InitializingBean {

    /**
     * 黑名单缓存key，注意和管理后台一致
     * 
     * com.jd.couponservice.test.controller.BlackUserController
     */
    private final String BLACK_USER_KEY = "couponOrderServices:black_users";
    private final String ERROR_MSG = "the user %s in the black user list";

    // 本地jvm黑名单
    private static Set<String> blackUsers = new HashSet<String>();

    @Resource
    private RedisUtils redisUtils;
    private boolean enable = true;

    Logger logger = LoggerFactory.getLogger(BlackFilterAspect.class);

    @Pointcut("execution(public * com.jd.couponservice.client.service.CouponService.*(..)) || execution(public * com.jd.couponservice.cxfservice.CxfCouponService.getCouponsByPin(..))")
    public void blackFilterPointcut() {}

    @Around("blackFilterPointcut()")
    public Object execDegrade(ProceedingJoinPoint jp) throws Throwable {
        MethodSignature ms = (MethodSignature) jp.getSignature();
        String methodName = ms.getName();

        // 只拦截getAllCouponsWithCheck，getAvailableCoupons这两个优惠券列表api方法
        if (enable
            && ("getAllCouponsWithCheck".equals(methodName)
                || "getAvailableCoupons".equals(methodName) || "getCouponsByPin".equals(methodName))) {
            Object[] pns = jp.getArgs();
            String pin = (String) pns[0];

            if (blackUsers.contains(pin)) {

                if ("getAllCouponsWithCheck".equals(methodName)) {
                    CouponSopResult rs = new CouponSopResult();
                    rs.setSuccess(false);
                    rs.setResultCode(CouponResultCodeDict.SystemError);
                    rs.setErrorMsg(String.format(ERROR_MSG, pin));
                    return rs;
                }

                if ("getAvailableCoupons".equals(methodName)
                    || "getCouponsByPin".equals(methodName)) {
                    CouponResult rs = new CouponResult();
                    rs.setSuccess(false);
                    rs.setResultCode(CouponResultCodeDict.SystemError);
                    rs.setErrorMsg(String.format(ERROR_MSG, pin));
                    return rs;
                }

            }

        }

        return jp.proceed();

    }

    @Override
    public void afterPropertiesSet() throws Exception {
        ScheduledExecutorService scheduledExecutorService = Executors.newSingleThreadScheduledExecutor(new NamedThreadFactory("--black user thread factory--",
                                                                                                                              true));

        scheduledExecutorService.scheduleWithFixedDelay(new Runnable() {
            public void run() {
                // 30秒同步一次数据
                try {
                    Set<String> remoteBlackUsers = redisUtils.smembers(BLACK_USER_KEY);

                    if (remoteBlackUsers != null) {
                        blackUsers = remoteBlackUsers;
                    }

                }
                catch (Throwable t) { // 防御性容错
                    logger.error("Unexpected error occur at sync black user data, cause: "
                                         + t.getMessage(),
                                 t);
                }
            }
        },
                                                        3,
                                                        30,
                                                        TimeUnit.SECONDS);

    }

    public void setEnable(boolean enable) {
        this.enable = enable;
    }

}