使用terracotta设置hibernate分布式ehcache时的会话工厂问题

Question

我正在尝试使用Terracotta在分布式环境中设置EHCache。在这里，我能够连接应用程序服务器和兵马俑服务器，在兵马俑开发人员控制台中，我能够看到复制的对象。

但是在应用程序服务器中不断出现以下异常消息，尽管应用程序的其余部分运行正常：

大家好，如果有人能指导一下为什么会出现这个异常消息，以及我们该如何解决它。此外，它将有助于我有任何全面的教程，为hibernate应用程序设置terracotta。

这里[CacheByAmitNode8081]是我在应用服务器中定义的缓存节点的名称。

[DEBUG][04/05/12 12:49:07.973][CacheByAmitNode8081] Running mbean initializer task for ehcache hibernate...
[DEBUG][04/05/12 12:49:07.995][CacheByAmitNode8081] Successfully registered bean
[ERROR][04/05/12 12:49:08.000][CacheByAmitNode8081] Error locating Hibernate Session Factory
java.lang.NullPointerException
at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:36)
at sun.reflect.UnsafeQualifiedObjectFieldAccessorImpl.get(UnsafeQualifiedObjectFieldAccessorImpl.java:20)
at java.lang.reflect.Field.get(Field.java:358)
at org.hibernate.cache.ehcache.management.impl.ProviderMBeanRegistrationHelper$RegisterMBeansTask.locateSessionFactory(ProviderMBeanRegistrationHelper.java:152)
at org.hibernate.cache.ehcache.management.impl.ProviderMBeanRegistrationHelper$RegisterMBeansTask.run(ProviderMBeanRegistrationHelper.java:117)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
[DEBUG][04/05/12 12:49:08.001][CacheByAmitNode8081] SessionFactory is probably still being initialized... waiting for it to complete before enabling hibernate statistics monitoring via JMX
[DEBUG][04/05/12 12:49:08.001][CacheByAmitNode8081] Running mbean initializer task for ehcache hibernate...
[ERROR][04/05/12 12:49:08.001][CacheByAmitNode8081] Error locating Hibernate Session Factory
java.lang.NullPointerException
at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:36)
at sun.reflect.UnsafeQualifiedObjectFieldAccessorImpl.get(UnsafeQualifiedObjectFieldAccessorImpl.java:20)
at java.lang.reflect.Field.get(Field.java:358)
at org.hibernate.cache.ehcache.management.impl.ProviderMBeanRegistrationHelper$RegisterMBeansTask.locateSessionFactory(ProviderMBeanRegistrationHelper.java:152)
at org.hibernate.cache.ehcache.management.impl.ProviderMBeanRegistrationHelper$RegisterMBeansTask.run(ProviderMBeanRegistrationHelper.java:117)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)*

Answer 1

当你使用 Terracotta 时，你需要在类路径上添加特定的 terracotta jar 来取代 ehcache 实现。在您的异常堆栈中，我没有看到任何兵马俑类输出...

在我的maven依赖中，我有：

<dependency>
  <groupId>net.sf.ehcache</groupId>
  <artifactId>ehcache-core-ee</artifactId>
  <version>2.5.2</version>
  <scope>compile</scope>
</dependency>
<dependency>
  <groupId>net.sf.ehcache</groupId>
  <artifactId>ehcache-terracotta-ee</artifactId>
  <version>2.5.2</version>
  <scope>compile</scope>
</dependency>
<dependency>
  <groupId>org.terracotta</groupId>
  <artifactId>terracotta-toolkit-1.5-runtime-ee</artifactId>
  <version>4.2.0</version>
  <scope>compile</scope>
</dependency>

您还可以查看兵马俑教程，了解如何插入Hibernate：http://terracotta.org/documentation/enterprise-ehcache/get-started-hibernate