publicclassRedisAtomicOperation{privateJedisjedis;publicRedisAtomicOperation(Jedisjedis){this.jedis=jedis;// 注入 Jedis 实例}publicStringgetAndDelete(Stringkey){// Lua 脚本,获取值并删除StringluaScript="local value = redi
publicStringdeleteKeyAndReturnValue(Jedisjedis,Stringkey){// 获取值Stringvalue=getValueBeforeDelete(jedis,key);// 删除键deleteKey(jedis,key);returnvalue;// 返回被删除的值} 1. 2. 3. 4. 5. 6. 7. 整合代码 将以上步骤整合到一起,我们可以得到一个完整的 Java 类: importredis.clients.jedis.Jedis...
).set(key, value, timeOut, timeUnit); result =true;}catch(Exception e){ e.printStackTrace();}return result;}/** * 更新缓存 */publicbooleangetAndSet(finalString key,String value){ boolean result =false;try{ redisTemplate.opsForValue().getAndSet(key, value); result =true;}...
importlombok.extern.slf4j.Slf4j;importorg.springframework.beans.factory.annotation.Autowired;importorg.springframework.data.redis.core.RedisTemplate;importorg.springframework.stereotype.Component;importorg.springframework.util.CollectionUtils;importjava.util.*;importjava.util.concurrent.TimeUnit; @Component @Slf...
public long getExpire(String key) { return redisTemplate.getExpire(key, TimeUnit.SECONDS); } /** * 判断key是否存在 * @param key 键 * @return true 存在 false不存在 */ public boolean hasKey(String key) { try { return redisTemplate.hasKey(key); ...
close(); //测试String redisTemplate.opsForValue().set("k1","v1"); System.out.println("k1旧值:"+redisTemplate.opsForValue().getAndSet("k1","V1111")); System.out.println("k1新值:"+redisTemplate.opsForValue().get("k1")); //测试set redisTemplate.opsForSet().add("a",1,2,3); ...
} @Override public Boolean del(String key) { return redisTemplate.delete(key); ...
根据OpenJDK 8的源码我们可以看出,getAndAddInt()循环获取给定对象o中的偏移量处的值v,然后判断内存值是否等于v。如果相等则将内存值设置为 v + delta,否则返回false,继续循环进行重试,直到设置成功才能退出循环,并且将旧值返回。整个“比较+更新”操作封装在compareAndSwapInt()中,在JNI里是借助于一个CPU指令完成...
Redis是一个高性能的内存数据库,支持分布式锁的实现。基于Redis实现分布式锁的步骤如下: (1)获取Redis连接 (2)使用setnx命令设置键值对,如果返回值为1,则表示获取锁成功,否则获取锁失败 (3)如果获取锁失败,则使用get命令获取锁的值,并判断当前时间是否大于锁的超时时间,如果是,则使用getset命令设置新的锁值,并判...
ashOperations<String, String, Boolean> hashOperations = redisTemplate.opsForHash();hashOperations.delete("key", userId);执行后报如下错误err:Handler dispatch failed; nested exception is java.l...