Fetching Mails to Space Fails Due to [Ljava.lang.Object; cannot be cast to com.atlassian.confluence.content.CustomContentEntityObject
Platform Notice: Data Center - This article applies to Atlassian products on the Data Center platform.
Note that this knowledge base article was created for the Data Center version of the product. Data Center knowledge base articles for non-Data Center-specific features may also work for Server versions of the product, however they have not been tested. Support for Server* products ended on February 15th 2024. If you are running a Server product, you can visit the Atlassian Server end of support announcement to review your migration options.
*Except Fisheye and Crucible
Symptoms
After an upgrade from to Confluence 4.2.x, Confluence failed to fetch mails if mail-user in Lotus Notes Domino is forbidden from deleting mails from the database. However, this might used to work before with the same setting in Confluence 4.1.x or earlier.
The following appears in the atlassian-confluence.log:
ERROR [scheduler_Worker-3] [confluence.mail.archive.DefaultMailAccountManager] poll Error retrieving mail from POP3 account [eas@www.sea.net:110] for space TCOMEAS: [Ljava.lang.Object; cannot be cast to com.atlassian.confluence.content.CustomContentEntityObject
java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.atlassian.confluence.content.CustomContentEntityObject
at com.atlassian.confluence.mail.archive.content.DefaultMailContentManager.getMailItemFromSpace(DefaultMailContentManager.java:217)
at com.atlassian.confluence.mail.archive.content.DefaultMailContentManager.storeIncomingMail(DefaultMailContentManager.java:102)
at com.atlassian.confluence.mail.archive.DefaultMailAccountManager.retrieveMessages(DefaultMailAccountManager.java:183)
at com.atlassian.confluence.mail.archive.DefaultMailAccountManager.poll(DefaultMailAccountManager.java:128)
at com.atlassian.confluence.mail.archive.DefaultMailAccountManager.poll(DefaultMailAccountManager.java:84)
at com.atlassian.confluence.mail.archive.DefaultMailAccountManager.pollAllSpaces(DefaultMailAccountManager.java:284)
at com.atlassian.confluence.mail.archive.jobs.MailPollJob$1.doInTransaction(MailPollJob.java:35)
at com.atlassian.confluence.mail.archive.jobs.MailPollJob$1.doInTransaction(MailPollJob.java:31)
at com.atlassian.sal.core.transaction.HostContextTransactionTemplate$1.doInTransaction(HostContextTransactionTemplate.java:25)
at com.atlassian.sal.spring.component.SpringHostContextAccessor$1.doInTransaction(SpringHostContextAccessor.java:88)
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:128)
at com.atlassian.sal.spring.component.SpringHostContextAccessor.doInTransaction(SpringHostContextAccessor.java:82)
at sun.reflect.GeneratedMethodAccessor97.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.atlassian.plugin.osgi.hostcomponents.impl.DefaultComponentRegistrar$ContextClassLoaderSettingInvocationHandler.invoke(DefaultComponentRegistrar.java:129)
at $Proxy249.doInTransaction(Unknown Source)
at sun.reflect.GeneratedMethodAccessor97.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.atlassian.plugin.osgi.bridge.external.HostComponentFactoryBean$DynamicServiceInvocationHandler.invoke(HostComponentFactoryBean.java:154)
at $Proxy249.doInTransaction(Unknown Source)
at com.atlassian.sal.core.transaction.HostContextTransactionTemplate.execute(HostContextTransactionTemplate.java:21)
at sun.reflect.GeneratedMethodAccessor176.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
at org.springframework.osgi.service.importer.support.internal.aop.ServiceInvoker.doInvoke(ServiceInvoker.java:58)
at org.springframework.osgi.service.importer.support.internal.aop.ServiceInvoker.invoke(ServiceInvoker.java:62)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.osgi.service.util.internal.aop.ServiceTCCLInterceptor.invokeUnprivileged(ServiceTCCLInterceptor.java:56)
at org.springframework.osgi.service.util.internal.aop.ServiceTCCLInterceptor.invoke(ServiceTCCLInterceptor.java:39)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.osgi.service.importer.support.LocalBundleContextAdvice.invoke(LocalBundleContextAdvice.java:59)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy383.execute(Unknown Source)
at com.atlassian.confluence.mail.archive.jobs.MailPollJob.doExecute(MailPollJob.java:31)
at com.atlassian.quartz.jobs.AbstractJob.executeInternal(AbstractJob.java:86)
at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
at org.quartz.core.JobRunShell.run(JobRunShell.java:199)
at com.atlassian.confluence.schedule.quartz.ConfluenceQuartzThreadPool$1.run(ConfluenceQuartzThreadPool.java:20)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:549)Cause
The cause is still unknown but could be due to Mail Archiving became a bundled plug-in in Confluence 4.2. The issue is tracked here: CONFSERVER-26036 - Error retrieving message: [Ljava.lang.Object; cannot be cast to com.atlassian.confluence.content.CustomContentEntityObject.
Resolution
Allow mail-user to delete emails from the mail database and the issue will not appear.
Certain organization forbid their mail-users from deleting mails from the database because the database is used for other applications. In this case, you can duplicate the mail databases for Confluence and allow the users to delete the mails.