Hibernate-Redis集成
介绍
在Spring Boot 中，以JPA为ORM框架的微服务，默认是二级缓存是关闭的。因为在分布式集群架构下，本地的二级缓存必然会带来多个微服务实例缓存不一致问题。将二级缓存移交给第三方中间件可以很好的解决缓存不一致问题。并且Redis一款高性能的K-V存储中间件，在保证缓存一致性的同时，还能提供高性能，高可用的特性。本篇文章就是基于开源框架hibernate-redisGitHub地址，将redis集成到微服务中作为JPA中作为二级缓存存储中间件。
###集成
在hibernate-redisConfiguration官方给很多种集成方式，针对于不同redis模式(redis单体模式，主从模式，哨兵模式,集群模式)给出了不同配置说明，本文为以最简单redis单体模式，将redis集成到服务中。
0. redis安装启动
将redis安装并启动，本文redis的地址为：127.0.0.1:6379
1. 引入pom
<dependency>
<groupId>com.github.debop</groupId>
<artifactId>hibernate-redis</artifactId>
<version>2.4.0</version>
</dependency>
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson</artifactId>
<version>2.5.1</version>
</dependency>
<dependency>
<groupId>de.ruedigermoeller</groupId>
<artifactId>fst</artifactId>
<version>2.48</version>
</dependency>
<dependency>
<groupId>org.xerial.snappy</groupId>
<artifactId>snappy-java</artifactId>
<version>1.1.7.3</version>
</dependency>2 . 配置
A . 在 src/main/resources/application.yml 配置数据源和开启二级缓存
spring:
application:
name: jps-redis-demo
datasource:
username: root
password: *****
url: jdbc:mysql://localhost:3306/tenant-center?&useUnicode=true&characterEncoding=UTF-8&useSSL=false
driver-class-name: com.mysql.cj.jdbc.Driver
type: com.alibaba.druid.pool.DruidDataSource
jpa:
hibernate:
naming:
physical-strategy: org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
ddl-auto: update
database-platform: org.hibernate.dialect.MySQL5InnoDBDialect
properties:
## 缓存策略，总是缓存
javax:
persistence:
sharedCache:
mode: ALL
##二级缓存配置
hibernate:
cache:
## 开启二级缓存
use_second_level_cache: true
## 查询缓存
use_query_cache: true
## RedisRegionFactory
region:
factory_class: org.hibernate.cache.redis.hibernate52.SingletonRedisRegionFactory
## 缓存标示前缀
region_prefix: hibernate
## 结构化缓存实体
use_structured_entries: true
## 配置文件路径
provider_configuration_file_resource_path: classpath:conf/hibernate-redis.properties
redisson-config: classpath:conf/redisson.yaml
redis:
expiryInSeconds:
default: 120
hibernate:
common: 0
account: 1200
show-sql: true缓存模式 javax.persistence.shared.Cache.mode
官方解释：SharedCacheMode
文本以ALL 表示：所有实体都缓存
B . 在 src/main/resources/创建 conf目录存放hibernate-redis的配置文件，并创建hibernate-redis.properties 和 redisson.yaml 配置文件
hibernate-redis.properties 配置文件：
redisson-config=classpath:conf/redisson.yaml
#
# Cache Expiry settings
# 'hibernate' is second cache prefix
# 'common', 'account' is actual region name
#
# default = 120 seconds (2 minutes) (see RedisCacheUtil.DEFAULT_EXPIRY_IN_SECONDS)
#
redis.expiryInSeconds.default=360
redis.expiryInSeconds.hibernate.common=0
redis.expiryInSeconds.hibernate.account=1200redisson.yaml 配置文件：
singleServerConfig:
## If pooled connection not used for a timeout time and current connections amount bigger than minimum idle connections pool size, then it will closed and removed from pool. Value in milliseconds.
idleConnectionTimeout: 10000
## Timeout during connecting to any Redis server.
connectTimeout: 10000
## Redis server response timeout. Starts to countdown when Redis command was succesfully sent. Value in milliseconds.
timeout: 3000
## Error will be thrown if Redis command can't be sended to Redis server after retryAttempts. But if it sent succesfully then timeout will be started.
retryAttempts: 3
## Time interval after which another one attempt to send Redis command will be executed. Value in milliseconds
retryInterval: 1500
## Password for Redis server authentication
password: null
## Subscriptions per subscribe connection limit. Used by RTopic, RPatternTopic, RLock, RSemaphore, RCountDownLatch, RClusteredLocalCachedMap, RClusteredLocalCachedMapCache, RLocalCachedMap, RLocalCachedMapCache objects and Hibernate READ_WRITE cache strategy.
subscriptionsPerConnection: 5
## Name of client connection
clientName: null
## Redis server address in host:port format. Use rediss:// protocol for SSL connection.
address:
- "redis://127.0.0.1:6379"
## Minimum idle Redis subscription connection amount.
subscriptionConnectionMinimumIdleSize: 1
## Redis subscription connection maximum pool size.
subscriptionConnectionPoolSize: 50
## Minimum idle Redis connection amount.
connectionMinimumIdleSize: 24
## Redis connection maximum pool size.
connectionPoolSize: 64
## Database index used for Redis connection
database: 0
## DNS change monitoring interval. Applications must ensure the JVM DNS cache TTL is low enough to support this. Set -1 to disable. Multiple IP bindings for single hostname supported in Proxy mode.
dnsMonitoringInterval: 5000
threads: 16
## Threads amount shared between all redis clients used by Redisson. Netty threads used in Redis response decoding and command sending.
nettyThreads: 32
## Redis data codec. Used during read and write Redis data. Several implementations are available:
codec: !<org.redisson.codec.FstCodec> {}
## Available values: default TransportMode.NIO
#TransportMode.NIO,
#TransportMode.EPOLL - requires netty-transport-native-epoll lib in classpath
#TransportMode.KQUEUE - requires netty-transport-native-kqueue lib in classpath
## transportMode: "NIO"配置文件中都有关于配置的官方说明，其中transportMode:"NIO" 为默认配置，可以不配置，配置会导致文件格式解析问题。
3 . 注解启动
在启动类上加入缓存启动注解
@SpringBootApplication
@EnableCaching
public class JpaRedisDemoApplication {
public static void main(String[] args) { SpringApplication.run(JpaRedisDemoApplication.class, args);}
}3 . 创建实体测试
创建相应的实体测试二级缓存是否生效。
就这样简单四个步骤就可以将hibernate-redis集成到JPA中
版本说明
hibernate-redis 官方发布的版本为2.3.2 ，可以支持hibernate (4.x, 5.1.x, 5.2.x) ，但是本文在集成该hibernate-core-5.2.11.Final版本，
出现问题：
官方的问题列表中也存在这个问题，并且说明在hibernate-redis-2.4.0 版本中解决，但2.4.0 版本还未发布，需要手动下载jar，并安装到本地仓库中去
下载地址：hibernate-redis-2.4.0
安装命令：
mvn install:install-file -Dfile=hibernate-redis-2.4.0.jar -DgroupId=com.github.debop -DartifactId=hibernate-redis -Dversion=2.4.0 -Dpackaging=jar
源代码实例
本篇源代码实例：jpa-redis-demo