Question

我正在尝试将Hibernate JPA与Google AppEngine一起用于与我的Google Cloud SQL实例进行通信。在创建用于保存数据的实体管理器工厂时，我在appengine日志中看到以下异常：

javax.persistence.PersistenceException: Unable to build entity manager factory
    at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:81)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39)
    ...
    com.google.apphosting.runtime.ThreadGroupPool$PoolEntry.run(ThreadGroupPool.java:251)
    at java.lang.Thread.run(Thread.java:724)

**Caused by: java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "modifyThreadGroup")**
    at java.security.AccessControlContext.checkPermission(AccessControlContext.java:375)
    at java.security.AccessController.checkPermission(AccessController.java:565)
    at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
    at com.google.apphosting.runtime.security.CustomSecurityManager.checkPermission(CustomSecurityManager.java:56)
    at com.google.apphosting.runtime.security.CustomSecurityManager.checkAccess(CustomSecurityManager.java:131)
    at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:315)
    at java.lang.Thread.init(Thread.java:378)
    at java.lang.Thread.<init>(Thread.java:654)
    at java.util.concurrent.Executors$DefaultThreadFactory.newThread(Executors.java:572)
    at java.util.concurrent.ThreadPoolExecutor$Worker.<init>(ThreadPoolExecutor.java:591)
    at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:922)
        ...

我在https://developers.google.com/appengine/articles/using_hibernate中创建了我的persistence.xml和代码，但仍然得到了modifyThreadGroup的RunTimeException。我正在使用Hibernate 4.3.1.Final。有谁知道如何解决这一问题？我查看了现有的modifyThreadGroup异常解决方案，但那些不适用于我，因为我没有在本地运行，我正在运行GAE实例，所以我不能在eclipse项目中取消选中“使用GAE”。

Answer 1

我今天遇到了同样的问题，我找到了另一个问题，答案对我有用。根据这个answer，您必须使用4.2.0.Final版本的Hibernate，因为在较新版本中，DriverManagerConnectionProvider会尝试创建新线程。

在Google AppEngine中使用Hibernate JPA时，modifyThreadGroup RuntimeException

1 个答案: