Redis分布式锁Java实现类
package com.utils; import java.util.Collections; import java.util.UUID; import redis.clients.jedis.Jedis; public class RedisTool { private static final String LOCK_SUCCESS = "OK"; private static final String SET_IF_NOT_EXIST = "NX"; private static final String SET_WITH_EXPIRE_TIME = "PX"; private static final String SCRIPT = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end"; private static final Long RELEASE_SUCCESS = 1L; // test private int count = 0; /** * 获取请求Id * @return 返回UUID */ public static String getRequestId(){ return UUID.randomUUID().toString(); } /** * 尝试获取分布式锁 * @param jedis Redis客户端 * @param lockKey 锁 * @param requestId 请求标识 * @param expireTime 超期时间 * @return 是否获取成功 */ public static boolean tryGetDistributedLock(Jedis jedis, String lockKey, String requestId, int expireTime) { String result = jedis.set(lockKey, requestId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, expireTime); if (LOCK_SUCCESS.equals(result)) { return true; } return false; } /** * 释放分布式锁 * @param jedis Redis客户端 * @param lockKey 锁 * @param requestId 请求标识 * @return 是否释放成功 */ public static boolean releaseDistributedLock(Jedis jedis, String lockKey, String requestId) { Object result = jedis.eval(SCRIPT, Collections.singletonList(lockKey), Collections.singletonList(requestId)); if (RELEASE_SUCCESS.equals(result)) { return true; } return false; } public static void main(String[] args) { RedisTool redisTool = new RedisTool(); redisTool.testDistributedLock(); } public void testDistributedLock() { for (int i = 0; i < 10; i++) { new Thread(new Runnable() { @Override public void run() { Jedis jedis = new Jedis("localhost"); String lockKey = "lock"; String requestId = getRequestId(); // 加锁 if (tryGetDistributedLock(jedis, lockKey, requestId, 10)) { count++; System.out.println(requestId + ":" + count); // 解锁 releaseDistributedLock(jedis, lockKey, requestId); } else { System.out.println(requestId + ": tryGetDistributedLock fail"); } } }); } } }
转自:http://www.importnew.com/27477.html