hibernate - 防止Grails中过时的状态错误

Question

我遇到了一堆线程同时访问的方法的问题。该方案是线程A遍历列表，创建并保存域对象。当线程A仍在迭代时，线程B调用相同的方法，尝试访问线程A创建的域对象，并引发StaleStateException。

为了显示:

def populateStudents(listOfStudents) {

   listOfStudents.each { Student student ->
      def schoolName = student.schoolName
      def school = School.findByName(schoolName) ?: new School(name: schoolName).save(flush:true)

      student.addToSchools(school)

      // So Thread A creates a new School domain object and continues to iterate.
      // Thread B comes along and finds the domain created by Thread A.
      // However, it appears that the StaleStateException is thrown when Thread B tries to addToSchools

   }

}

这是堆栈:

org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): [com.app.School#60]
    at org.hibernate.persister.entity.AbstractEntityPersister.check(AbstractEntityPersister.java:1792)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2435)
    at org.hibernate.persister.entity.AbstractEntityPersister.updateOrInsert(AbstractEntityPersister.java:2335)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2635)
    at org.hibernate.action.EntityUpdateAction.execute(EntityUpdateAction.java:115)
    at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279)
    at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263)
    at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:168)
    at org.codehaus.groovy.grails.orm.hibernate.events.PatchedDefaultFlushEventListener.performExecutions(PatchedDefaultFlushEventListener.java:46)
    at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
    at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)
    at org.springframework.orm.hibernate3.HibernateTemplate$28.doInHibernate(HibernateTemplate.java:883)
    at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:406)
    at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:374)
    at org.springframework.orm.hibernate3.HibernateTemplate.flush(HibernateTemplate.java:881)
    at org.codehaus.groovy.grails.orm.hibernate.metaclass.MergePersistentMethod$1.doInHibernate(MergePersistentMethod.java:60)
    at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:406)
    at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:339)
    at org.codehaus.groovy.grails.orm.hibernate.metaclass.MergePersistentMethod.performSave(MergePersistentMethod.java:54)
    at org.codehaus.groovy.grails.orm.hibernate.metaclass.AbstractSavePersistentMethod.doInvokeInternal(AbstractSavePersistentMethod.java:179)
    at org.codehaus.groovy.grails.orm.hibernate.metaclass.AbstractDynamicPersistentMethod.invoke(AbstractDynamicPersistentMethod.java:59)
    at sun.reflect.GeneratedMethodAccessor23965.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoCachedMethodSite.invoke(PojoMetaMethodSite.java:188)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:52)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:132)
    at org.codehaus.groovy.grails.plugins.orm.hibernate.HibernatePluginSupport$_addBasicPersistenceMethods_closure73.doCall(HibernatePluginSupport.groovy:814)
    at sun.reflect.GeneratedMethodAccessor845.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:90)
    at org.codehaus.groovy.runtime.metaclass.ClosureMetaMethod.invoke(ClosureMetaMethod.java:80)
    at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite$PogoMetaMethodSiteNoUnwrapNoCoerce.invoke(PogoMetaMethodSite.java:307)
    at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite.call(PogoMetaMethodSite.java:63)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:124)
    at com.app.TransactionService$_populateStudents_closure3.doCall(TransactionService.groovy:96)
    at sun.reflect.GeneratedMethodAccessor24059.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:90)
    at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:233)
    at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1058)
    at groovy.lang.ExpandoMetaClass.invokeMethod(ExpandoMetaClass.java:1070)
    at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:886)
    at groovy.lang.Closure.call(Closure.java:282)
    at org.codehaus.groovy.runtime.DefaultGroovyMethods.eachWithIndex(DefaultGroovyMethods.java:1213)
    at org.codehaus.groovy.runtime.dgm$150.invoke(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoMetaMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:270)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:52)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:124)
    at com.app.TransactionService.populateStudents(TransactionService.groovy:49)
    at com.app.TransactionService$$FastClassByCGLIB$$1b289e99.invoke(<generated>)
    at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
    at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:688)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:621)
    at com.app.TransactionService$$EnhancerByCGLIB$$8986440c.populateStudents(<generated>)


INFO UpdateController - Object of class [com.app.School] with identifier [60]: optimistic locking failed; nested exception is org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): [com.app.School#60]

有任何想法吗

Answer 1

您可以使用pessimistic locking解决此问题:

def school = School.findByName(schoolName, [lock: true]) ?: new School(name: schoolName).save(flush:true)