Unexpected message conversion with MappingJackson2MessageConverter - spring-integration

Question

The snippet below works with 5.0.8.RELASE but fails with 5.1.0.RELEASE.
#Bean
public IntegrationFlow flow(RestTemplateBuilder restTemplateBuilder, MessageChannel outputChannel) {
return f -> f
.handle(Http.outboundGateway("http://localhost:80/test", restTemplateBuilder.build())
.httpMethod(HttpMethod.GET).expectedResponseType(String.class))
.enrichHeaders(h -> h.header(JsonHeaders.TYPE_ID, Response.class))
.transform(Transformers.fromJson())
.filter(Response.class, p -> true)
.channel(outputChannel);
}
public static class Response {
private int result;
public int getResult() { return result; }
public void setResult(int result) { this.result = result; }
}
The full stack trace is:
org.springframework.messaging.converter.MessageConversionException: Could not read JSON: Unrecognized token 'org': was expecting ('true', 'false' or 'null')
at [Source: (String)"org.example.Application$Response#2d195ee4"; line: 1, column: 4]; nested exception is com.fasterxml.jackson.core.JsonParseException: Unrecognized token 'org': was expecting ('true', 'false' or 'null')
at [Source: (String)"org.example.Application$Response#2d195ee4"; line: 1, column: 4], failedMessage=GenericMessage [payload=org.example.Application$Response#2d195ee4, headers={id=a621f44f-dc89-19b6-6c80-f372c86e755d, contentType=application/json, http_statusCode=200 OK, timestamp=1542638474438}]
at org.springframework.messaging.converter.MappingJackson2MessageConverter.convertFromInternal(MappingJackson2MessageConverter.java:234)
at org.springframework.messaging.converter.AbstractMessageConverter.fromMessage(AbstractMessageConverter.java:181)
at org.springframework.messaging.converter.AbstractMessageConverter.fromMessage(AbstractMessageConverter.java:172)
at org.springframework.messaging.converter.CompositeMessageConverter.fromMessage(CompositeMessageConverter.java:57)
at org.springframework.integration.handler.LambdaMessageProcessor.processMessage(LambdaMessageProcessor.java:112)
at org.springframework.integration.filter.AbstractMessageProcessingSelector.accept(AbstractMessageProcessingSelector.java:62)
at org.springframework.integration.filter.MessageFilter.doHandleRequestMessage(MessageFilter.java:165)
at org.springframework.integration.handler.AbstractReplyProducingPostProcessingMessageHandler.handleRequestMessage(AbstractReplyProducingPostProcessingMessageHandler.java:46)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:123)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:169)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:115)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:133)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:106)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:459)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:400)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:187)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:166)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:47)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:109)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:415)
at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:334)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:225)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:129)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:169)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:115)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:133)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:106)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:459)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:400)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:187)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:166)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:47)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:109)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:415)
at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:334)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:225)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:129)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:169)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:115)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:133)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:106)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:459)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:400)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:187)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:166)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:47)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:109)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:415)
at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:334)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:225)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:129)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:169)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:115)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:133)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:106)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:459)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:400)
at org.example.ApplicationTest.flow(ApplicationTest.java:46)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)
at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)
Caused by: com.fasterxml.jackson.core.JsonParseException: Unrecognized token 'org': was expecting ('true', 'false' or 'null')
at [Source: (String)"org.example.Application$Response#2d195ee4"; line: 1, column: 4]
at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:1804)
at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:679)
at com.fasterxml.jackson.core.json.ReaderBasedJsonParser._reportInvalidToken(ReaderBasedJsonParser.java:2839)
at com.fasterxml.jackson.core.json.ReaderBasedJsonParser._handleOddValue(ReaderBasedJsonParser.java:1891)
at com.fasterxml.jackson.core.json.ReaderBasedJsonParser.nextToken(ReaderBasedJsonParser.java:749)
at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:4141)
at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4000)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3042)
at org.springframework.messaging.converter.MappingJackson2MessageConverter.convertFromInternal(MappingJackson2MessageConverter.java:229)
... 92 more
However if the line .filter(Response.class, p -> true) is commented out, it works as expected.
For some reason, the MappingJackson2MessageConverter is used as a converter in the filter, although I think it shouldn't. In fact, the converters used in 5.1.0.RELEASE for the filter do not have many similarities to those used in 5.0.8.RELEASE. It seems to me that something has gone wrong in the registration process of the converters in 5.1.0.RELEASE. Is there a chance that this is indeed expected behaviour? How should the code be adjusted in this case?
A sample project can be found here. Please check org.example.FilterAfterJsonTransformation and org.example.FilterAfterJsonTransformationTest. Switch between erroneous and correct behaviour by toggling the version and/or commenting the aforementioned line.

Answer 1

That's really a bug (will fix soon).
Meanwhile you should avoid to use the filter() with extra class argument. If you still need that type in the filter function, you need to do an explicit cast manually.
Another trick is to remove a contentType header to not let that MappingJackson2MessageConverter to do its conversion logic.
UPDATE
The Pull Request on the matter: https://github.com/spring-projects/spring-integration/pull/2635