从 Hibernate 5.2 升级到 5.3 时 SingletonEhCacheRegionFactory 不再可用答案

【问题标题】：SingletonEhCacheRegionFactory is no longer available when upgrading from Hibernate 5.2 to 5.3从 Hibernate 5.2 升级到 5.3 时 SingletonEhCacheRegionFactory 不再可用
【发布时间】：2019-10-30 00:10:54
【问题描述】：

我从事的一个项目目前正在使用 Hibernate 版本 5.2.15.Final。配置二级缓存时，项目一直使用org.hibernate.cache.ehcache.SingletonEhCacheRegionFactory作为hibernate.cache.region.factory_class的值。

当我将 Hibernate 版本更改为 5.3.12.Final 时，SingletonEhCacheRegionFactory 不再包含在该包中。 net.sf.ehcache.hibernate 包中提供了一个具有相同名称的类，我可以使用它而不会出现编译错误。但如果我运行它，它会在尝试构建会话时出错：

org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.cache.spi.RegionFactory]

    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:275)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:237)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214)
    at org.hibernate.boot.internal.MetadataBuilderImpl$MetadataBuildingOptionsImpl.<init>(MetadataBuilderImpl.java:688)
    at org.hibernate.boot.internal.MetadataBuilderImpl.<init>(MetadataBuilderImpl.java:123)
    at org.hibernate.boot.internal.MetadataBuilderImpl.<init>(MetadataBuilderImpl.java:93)

如果我深入挖掘堆栈跟踪，真正的错误似乎是这样的：

Caused by: org.hibernate.boot.registry.selector.spi.StrategySelectionException: Unable to resolve name [net.sf.ehcache.hibernate.SingletonEhCacheRegionFactory] as strategy [org.hibernate.cache.spi.RegionFactory]
    at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.selectStrategyImplementor(StrategySelectorImpl.java:133)
    at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.resolveStrategy(StrategySelectorImpl.java:212)
    at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.resolveStrategy(StrategySelectorImpl.java:169)
    at org.hibernate.cache.internal.RegionFactoryInitiator.resolveRegionFactory(RegionFactoryInitiator.java:93)
    at org.hibernate.cache.internal.RegionFactoryInitiator.initiateService(RegionFactoryInitiator.java:47)
    at org.hibernate.cache.internal.RegionFactoryInitiator.initiateService(RegionFactoryInitiator.java:32)
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:94)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:263)
    ... 64 more
Caused by: org.hibernate.boot.registry.classloading.spi.ClassLoadingException: Unable to load class [net.sf.ehcache.hibernate.SingletonEhCacheRegionFactory]
    at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:137)
    at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.selectStrategyImplementor(StrategySelectorImpl.java:129)
    ... 71 more
Caused by: java.lang.NoClassDefFoundError: org/hibernate/cache/QueryResultsRegion
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:374)
    at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:131)
    ... 72 more
Caused by: java.lang.ClassNotFoundException: org.hibernate.cache.QueryResultsRegion
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
    ... 75 more

这是我的 pom.xml 依赖项的样子：

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>5.3.12.Final</version>
</dependency>
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-ehcache</artifactId>
    <version>5.3.12.Final</version>
</dependency>

<dependency>
    <groupId>net.sf.ehcache</groupId>
    <artifactId>ehcache-core</artifactId>
    <version>2.6.11</version>
    <exclusions>
        <exclusion>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-c3p0</artifactId>
    <version>5.3.12.Final</version>
</dependency>

【问题讨论】：

标签： java hibernate ehcache

【解决方案1】：

好的，我想我找到了问题所在。以前我的代码通过以下方式获取完整的类名和路径：

SingletonEhCacheRegionFactory.class.getCanonicalName()

但在 Hibernate 5.3 中，该类已被移至内部包，这就是我再也找不到它的原因。如果我使用带有旧包名称 ("org.hibernate.cache.ehcache.SingletonEhCacheRegionFactory") 的硬编码字符串，我将不再收到该异常。

【讨论】：