After migrating to Spring Integration 4 I've noticed that my logs become very clear, no exceptions. Looking deeper at the problem, found this commit:
1. Instead of logging throwable - now we log e.getMessage() and so, stack-trace is not available anymore. I could not find another lightweight and reliable way to log all exceptions, so propose to add second parameter (Throwable) again to the log statement:
2. This is probably not so important as first one, but anyway: by default we do not log exceptions anymore (only in debug level) and it might be not obvious for developers how find this place and enable logging of errors. I would propose to set logging level here to warn and everyone can suppress error messages in logging configuration.