redis锁

Posted 2021-03-10 lostguangtou

package com.ivhs.crm.utils;

import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.core.RedisCallback;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import redis.clients.jedis.JedisCommands;

import java.util.UUID;

/**
 * @Description: redis锁
 * @Version: 1.0
 */
@Component
public class RedisLock {

    @Autowired
    private RedisTemplate redisTemplate;

    public boolean setLock(String key,long expire){
        String result = (String) redisTemplate.execute(new RedisCallbackLock(key,expire));
        return !StringUtils.isEmpty(result);
    }

    public void unLock(String key){
        redisTemplate.delete(key);
    }

    class RedisCallbackLock implements RedisCallback{
        private String key;
        private long expire;//单位秒

        public RedisCallbackLock(String key, long expire) {
            this.key = key;
            this.expire = expire;
        }

        /**
         * @Description 如果key存在返回null否则返回OK
         * commands参数：如果取NX，则只有当key不存在是才进行set，如果取XX，则只有当key已经存在时才进行set
         *  EX代表秒，PX代表毫秒
         */
        @Override
        public String doInRedis(RedisConnection redisConnection) throws DataAccessException {
            JedisCommands commands = (JedisCommands) redisConnection.getNativeConnection();
            String uuid = UUID.randomUUID().toString();
            return commands.set(key, uuid, "NX", "EX", expire);
        }
    }
}