本篇内容主要讲解“JAVA怎么用redisUtils工具类来防止高并发获取缓存出现并发问题”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“JAVA怎么用redisUtils工具类来防止高并发获取缓存出现并发问题”吧!
计算
安全
数据库
网络和加速
企业服务
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.core.BoundHashOperations;
import org.springframework.data.redis.core.BoundValueOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.function.BiFunction;
import java.util.function.Function;
@Slf4j
public class RedisUtils{
/**
* @param redisTemplate redis操作模板工具
* @param key 缓存主键
* @param timeout 过期时间
* @param timeUnit 过期时间单位
* @return
* @description 方法描述
* @author kejie.huang
* @date 2019/10/18 9:20
*/
public static void expire(RedisTemplate<Object, Object> redisTemplate, String key, long timeout, TimeUnit timeUnit) {
boolean hasKey = redisTemplate.hasKey(key);
// 如果key存在
if (hasKey) {
// 获取过期时间是永久则设置
Long timeOut = redisTemplate.getExpire(key);
if (timeOut.intValue() == -1) {
redisTemplate.expire(key, timeout, timeUnit);
}
}
}
public static Object getValue(RedisTemplate<Object, Object> redisTemplate, String key, Function<String, Object> mappingFunction){
BoundValueOperations boundValueOperations = redisTemplate.boundValueOps(key);
Object value = boundValueOperations.get();
if(value == null){
synchronized (key.intern()){
value = boundValueOperations.get();
if(value == null){
value = mappingFunction.apply(key);
if(value != null){
boundValueOperations.set(value);
}
}
}
}
return value;
}
public static Object getHashValue(RedisTemplate<Object, Object> redisTemplate, String key, String hashKey, BiFunction<String, String, Object> mappingFunction){
BoundHashOperations boundHashOperations = redisTemplate.boundHashOps(key);
Object value = boundHashOperations.get(hashKey);
if(value == null){
synchronized (key.concat(hashKey).intern()){
value = boundHashOperations.get(hashKey);
if(value == null){
value = mappingFunction.apply(key, hashKey);
if(value != null){
boundHashOperations.put(hashKey, value);
}
}
}
}
return value;
}
public static Map<?, ?> getHashValue(RedisTemplate<Object, Object> redisTemplate, String key, Function<String, Map<?,?>> mappingFunction){
Map<?,?> entries = redisTemplate.opsForHash().entries(key);
if(entries == null){
synchronized (key.intern()){
if(!redisTemplate.hasKey(key)){
entries = mappingFunction.apply(key);
if(entries != null){
redisTemplate.opsForHash().putAll(key, entries);
}
}
}
}
return entries;
}
public static String getHashValue(StringRedisTemplate redisTemplate, String key, String hashKey, BiFunction<String, String, String> mappingFunction){
BoundHashOperations<String, String, String> boundHashOperations = redisTemplate.boundHashOps(key);
String value = boundHashOperations.get(hashKey);
if(value == null){
synchronized (key.concat(hashKey).intern()){
value = boundHashOperations.get(hashKey);
if(value == null){
value = mappingFunction.apply(key, hashKey);
if(value != null){
boundHashOperations.put(hashKey, value);
}
}
}
}
return value;
}
}到此，相信大家对“JAVA怎么用redisUtils工具类来防止高并发获取缓存出现并发问题”有了更深的了解，不妨来实际操作一番吧！这里是亿速云网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！
亿速云「云服务器」，即开即用、新一代英特尔至强铂金CPU、三副本存储NVMe SSD云盘，价格低至29元/月。点击查看>>
免责声明：本站发布的内容（图片、视频和文字）以原创、转载和分享为主，文章观点不代表本网站立场，如果涉及侵权请联系站长邮箱：is@yisu.com进行举报，并提供相关证据，一经查实，将立刻删除涉嫌侵权内容。
原文链接：https://my.oschina.net/u/3155476/blog/3121297
