普通方式

1. 直接看代码

   1. package com.whereta.jedis;import org.springframework.stereotype.Component;import redis.clients.jedis.Jedis;import redis.clients.jedis.JedisPool;import javax.annotation.Resource;import java.util.Calendar;import java.util.Date;import java.util.concurrent.TimeUnit;/** * Created by vincent on 15-10-14. */@Component("jedisLock")public class JedisLock {    public class CacheName {        public static final String ADD_BEAN_AFTER_CHECK_LOCK_KEY = "ADDBeanAfterCheckLock";    }    @Resource    private JedisPool jedisPool;    public void addBeanAfterCheck(int userId) {        Jedis jedis = jedisPool.getResource();        Calendar calendar = Calendar.getInstance();        calendar.set(Calendar.MILLISECOND, 0);        Date calendarTime = calendar.getTime();        long time = calendarTime.getTime();        //以用户ｉｄ为ｋｅｙ，不同用户调用同一个方法不会加锁        String key = CacheName.ADD_BEAN_AFTER_CHECK_LOCK_KEY + ":" + userId;        try {            if (jedis != null) {                Long lock = jedis.setnx(key, time + "");                while (lock == 0) {                    TimeUnit.MILLISECONDS.sleep(50);                    lock = jedis.setnx(key, time + "");                }                //设置超时时间                jedis.expire(key, 3);            }            //自己的业务逻辑处理        } catch (Exception e) {            throw new RuntimeException(e);        } finally {            if (jedis != null) {                jedis.del(key);                jedis.close();            }        }    }}

2. 示例中以用户ｉｄ为ｋｅｙ加锁：不同用户访问该方法的时候不会排斥等待

3. 锁机制的实现利用了Redis的setnx方法：如果数据库里key存在了则不存储数据，返回０

4. redis的该方法是线程安全的，可以放心使用

ａｏｐ方式

1. 示例代码

   1. package com.whereta.jedis;import org.aspectj.lang.ProceedingJoinPoint;import org.aspectj.lang.annotation.Around;import org.aspectj.lang.annotation.Aspect;import org.springframework.stereotype.Component;import redis.clients.jedis.Jedis;import redis.clients.jedis.JedisPool;import javax.annotation.Resource;import java.util.Calendar;import java.util.Date;import java.util.concurrent.TimeUnit;/** * Created by vincent on 15-10-14. */@Aspect@Componentpublic class JedisLockAop {    @Resource    private JedisPool jedisPool;    @Around("execution(public * com.heli.core.pay.soaservice.impl.*.*(..))")    public Object serviceAOP(ProceedingJoinPoint point) {        Object proceed = null;        Jedis jedis = jedisPool.getResource();        Calendar calendar = Calendar.getInstance();        calendar.set(Calendar.MILLISECOND, 0);        Date calendarTime = calendar.getTime();        long time = calendarTime.getTime();        //请求参数数组        Object[] args = point.getArgs();        //key可以自定义        String key = JedisLock.CacheName.ADD_BEAN_AFTER_CHECK_LOCK_KEY + ":" + args[0];        try {            if (jedis != null) {                Long lock = jedis.setnx(key, time + "");                while (lock == 0) {                    TimeUnit.MILLISECONDS.sleep(50);                    lock = jedis.setnx(key, time + "");                }                //设置超时时间                jedis.expire(key, 3);            }            //用户业务处理            proceed = point.proceed();            return proceed;        } catch (Throwable throwable) {            throw new RuntimeException(throwable);        } finally {            if (jedis != null) {                jedis.del(key);                jedis.close();            }        }    }}

2. 使用Spring　Ａｏｐ的环绕方法

3. 具体ｋｅｙ值可以自定义涉及，譬如：ip，时间等