Redis分布式鎖

標籤：redis分布式   nts   default   col   分布   port   ESS   The   ted   

 1 package com.zad.jedis; 2  3 import redis.clients.jedis.Jedis; 4  5 import java.util.Collections; 6  7 /** 8  * 描述: 9  * 分布式鎖10  *11  * @author zad12  * @create 2018-09-14 13:5813  */14 public class Distributed {15     private static final String LOCK_SUCCESS = "OK";16     private static final String SET_IF_NOT_EXIST = "NX";17     private static final String SET_WITH_EXPIRE_TIME = "PX";18     private static final Integer RELEASE_SUCCESS = 1;19     private static final Integer DEFAULT_TIME = 5;20 21     /**22      * 嘗試擷取分布式鎖23      *24      * @param jedis      Redis用戶端25      * @param lockKey    鎖26      * @param requestId  請求標識27      * @return 是否擷取成功28      */29     public static boolean tryGetDistributedLock(Jedis jedis, String lockKey, String requestId) {30 31         String result = jedis.set(lockKey, requestId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, DEFAULT_TIME);32 33         if (LOCK_SUCCESS.equals(result)) {34             return true;35         }36         return false;37 38     }39 40 41     /**42      * 嘗試擷取分布式鎖43      *44      * @param jedis      Redis用戶端45      * @param lockKey    鎖46      * @param requestId  請求標識47      * @param expireTime 超期時間48      * @return 是否擷取成功49      */50     public static boolean tryGetDistributedLock(Jedis jedis, String lockKey, String requestId, int expireTime) {51 52         String result = jedis.set(lockKey, requestId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, expireTime);53 54         if (LOCK_SUCCESS.equals(result)) {55             return true;56         }57         return false;58 59     }60 61     /**62      * 釋放分布式鎖63      *64      * @param jedis     Redis用戶端65      * @param lockKey   鎖66      * @param requestId 請求標識67      * @return 是否釋放成功68      */69     public static boolean releaseDistributedLock(Jedis jedis, String lockKey, String requestId) {70 71         String script = "if redis.call(‘get‘, KEYS[1]) == ARGV[1] then return redis.call(‘del‘, KEYS[1]) else return 0 end";72         Object result = jedis.eval(script, Collections.singletonList(lockKey), Collections.singletonList(requestId));73 74         if (RELEASE_SUCCESS.equals(result)) {75             return true;76         }77         return false;78 79     }80 }

 

Redis分布式鎖