Spring integration mail inbound adapter throws exception when mail is deleted

Question

I have configured the following imap-inbound-adapter to receive already seen mails from an inbox. The mails should be deleted after they were received, so I set the "should be deleted" flag to "true". I am using the spring-boot-starter-integration with version 1.4.1.

@Configuration
public class MailDeleteAdapterConfiguration {

@Bean
public IntegrationFlow deleteMailFlow(MailNotifierProperties properties,
                                      SeenSearchTermStrategy seenSearchTermStrategy,
                                      DeleteMailHandler deleteMailHandler
) {
    return IntegrationFlows
            .from(Mail.imapInboundAdapter(properties.getImapUrl())
                    .javaMailProperties(p -> p
                            .put("mail.imap.starttls.enable", "true")
                            .put("mail.imap.ssl.trust", "*"))
                    .searchTermStrategy(seenSearchTermStrategy)
                    .shouldDeleteMessages(true)
            )
            .handle(deleteMailHandler)
            .get();
}

@Bean(name = PollerMetadata.DEFAULT_POLLER)
public PollerMetadata poller() {
    return Pollers.fixedRate(10000).maxMessagesPerPoll(100).get();
}

}

The mails are deleted, but there is also a exception thrown by the framework:

    org.springframework.messaging.MessageHandlingException: nested exception is java.lang.NullPointerException
    at org.springframework.integration.handler.MethodInvokingMessageProcessor.processMessage(MethodInvokingMessageProcessor.java:96) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.router.AbstractMessageProcessingRouter.getChannelKeys(AbstractMessageProcessingRouter.java:80) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.router.AbstractMappingMessageRouter.determineTargetChannels(AbstractMappingMessageRouter.java:185) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.router.AbstractMessageRouter.handleMessageInternal(AbstractMessageRouter.java:182) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.dispatcher.BroadcastingDispatcher.invokeHandler(BroadcastingDispatcher.java:236) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.dispatcher.BroadcastingDispatcher.dispatch(BroadcastingDispatcher.java:185) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:77) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:423) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.channel.MessagePublishingErrorHandler.handleError(MessagePublishingErrorHandler.java:95) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.util.ErrorHandlingTaskExecutor$1.run(ErrorHandlingTaskExecutor.java:58) [spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50) [spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.integration.util.ErrorHandlingTaskExecutor.execute(ErrorHandlingTaskExecutor.java:51) [spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint$Poller.run(AbstractPollingEndpoint.java:344) [spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54) [spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81) [spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_121]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_121]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_121]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) [na:1.8.0_121]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_121]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_121]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]
Caused by: java.lang.NullPointerException: null
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_121]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_121]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_121]
    at org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:113) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:129) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.ast.MethodReference.access$000(MethodReference.java:49) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.ast.MethodReference$MethodValueRef.getValue(MethodReference.java:347) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:88) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:131) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:330) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.integration.util.AbstractExpressionEvaluator.evaluateExpression(AbstractExpressionEvaluator.java:169) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.util.MessagingMethodInvokerHelper.processInternal(MessagingMethodInvokerHelper.java:317) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.util.MessagingMethodInvokerHelper.process(MessagingMethodInvokerHelper.java:155) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.handler.MethodInvokingMessageProcessor.processMessage(MethodInvokingMessageProcessor.java:93) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    ... 22 common frames omitted

2018-01-22 15:29:02.223 ERROR 25726 --- [ask-scheduler-4] o.s.i.c.MessagePublishingErrorHandler    : failure occurred in messaging task

org.springframework.messaging.MessagingException: failure occurred while polling for mail; nested exception is javax.mail.MessagingException: IOException while copying message;
  nested exception is:
    com.sun.mail.util.MessageRemovedIOException
    at org.springframework.integration.mail.MailReceivingMessageSource.receive(MailReceivingMessageSource.java:131) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.SourcePollingChannelAdapter.receiveMessage(SourcePollingChannelAdapter.java:209) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint.doPoll(AbstractPollingEndpoint.java:245) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint.access$000(AbstractPollingEndpoint.java:58) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint$1.call(AbstractPollingEndpoint.java:190) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint$1.call(AbstractPollingEndpoint.java:186) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint$Poller$1.run(AbstractPollingEndpoint.java:353) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.util.ErrorHandlingTaskExecutor$1.run(ErrorHandlingTaskExecutor.java:55) ~[spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50) [spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.integration.util.ErrorHandlingTaskExecutor.execute(ErrorHandlingTaskExecutor.java:51) [spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.AbstractPollingEndpoint$Poller.run(AbstractPollingEndpoint.java:344) [spring-integration-core-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54) [spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81) [spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_121]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_121]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_121]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) [na:1.8.0_121]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_121]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_121]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]
Caused by: javax.mail.MessagingException: IOException while copying message
    at javax.mail.internet.MimeMessage.<init>(MimeMessage.java:254) ~[javax.mail-api-1.5.5.jar:1.5.5]
    at org.springframework.integration.mail.AbstractMailReceiver$IntegrationMimeMessage.<init>(AbstractMailReceiver.java:557) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.mail.AbstractMailReceiver$IntegrationMimeMessage.<init>(AbstractMailReceiver.java:552) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.mail.AbstractMailReceiver.postProcessFilteredMessages(AbstractMailReceiver.java:415) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.mail.AbstractMailReceiver.receive(AbstractMailReceiver.java:342) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.mail.MailReceivingMessageSource.receive(MailReceivingMessageSource.java:112) ~[spring-integration-mail-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    ... 19 common frames omitted
Caused by: com.sun.mail.util.MessageRemovedIOException: null
    at com.sun.mail.imap.IMAPInputStream.forceCheckExpunged(IMAPInputStream.java:113) ~[javax.mail-1.5.5.jar:1.5.5]
    at com.sun.mail.imap.IMAPInputStream.fill(IMAPInputStream.java:166) ~[javax.mail-1.5.5.jar:1.5.5]
    at com.sun.mail.imap.IMAPInputStream.read(IMAPInputStream.java:218) ~[javax.mail-1.5.5.jar:1.5.5]
    at com.sun.mail.imap.IMAPInputStream.read(IMAPInputStream.java:244) ~[javax.mail-1.5.5.jar:1.5.5]
    at com.sun.mail.imap.IMAPMessage.writeTo(IMAPMessage.java:849) ~[javax.mail-1.5.5.jar:1.5.5]
    at javax.mail.internet.MimeMessage.<init>(MimeMessage.java:245) ~[javax.mail-api-1.5.5.jar:1.5.5]
    ... 24 common frames omitted

I had the mail.debug property set to "true", but I did not receive any hint for an error:

2018-01-22 15:54:24.702  INFO 27337 --- [ask-scheduler-1] o.s.integration.mail.ImapMailReceiver    : attempting to receive mail from folder [INBOX]
A32 SEARCH SEEN ALL
* SEARCH 1
A32 OK SEARCH completed in 0.00 s
A33 FETCH 1 (ENVELOPE INTERNALDATE RFC822.SIZE FLAGS BODYSTRUCTURE)
* 1 FETCH (ENVELOPE (CONTENT......))
A33 OK FETCH completed
A34 STORE 1 +FLAGS (\Flagged)
* 1 FETCH (FLAGS (\Seen \Flagged))
A34 OK STORE completed
A35 STORE 1 +FLAGS (\Seen)
* 1 FETCH (FLAGS (\Seen \Flagged))
A35 OK STORE completed
A36 STORE 1 +FLAGS (\Deleted)
* 1 FETCH (FLAGS (\Seen \Flagged \Deleted))
A36 OK STORE completed
A37 FETCH 1 (BODY.PEEK[]<0.16384>)
A37 NO FETCH Some of the requested messages no longer exist
DEBUG IMAP: IMAPProtocol noop
A38 NOOP
* 1 EXPUNGE
* 0 EXISTS
A38 OK NOOP completed
A39 CLOSE
A39 OK CLOSE completed
DEBUG IMAP: added an Authenticated connection -- size: 1

Mayby anyone has used the inbound adapter with the delete flag set to true successfully and can share a solution.

Answer 1

The server you're using seems to be broken. It's removing the message immediately even though you just marked it as deleted. Normally the message is not removed until you do an expunge. Perhaps there's a setting on the server that controls this behavior?