1. What's new in Spring Integration 4.0?

This chapter provides an overview of the new features and improvements that have been introduced with Spring Integration 4.0. If you are interested in more details, please see the Issue Tracker tickets that were resolved as part of the 4.0 development process.

1.1 New Components

1.1.1 MQTT Channel Adapters

The MQTT channel adapters (previously available in the Spring Integration Extensions repository) are now available as part of the normal Spring Integration distribution. See Chapter 22, MQTT Support

1.2 General Changes

Core messaging abstractions (Message, MessageChannel etc) have moved to the Spring Framework spring-messaging module. Users who reference these classes directly in their code will need to make changes as described in the first section of the Migration Guide.

1.2.1 Header Type for XPath Header Enricher

The header-type attribute has been introduced for the header sub-element of the <int-xml:xpath-header-enricher>. This attribute provides the target type for the header value to which the result of the XPath expression evaluation will be converted. For more information see Section 32.7, “XPath Header Enricher”.

1.2.2 Object To Json Transformer: Node Result

The result-type attribute has been introduced for the <int:object-to-json-transformer>. This attribute provides the target type for the result of object mapping to JSON. It supports STRING (default) and NODE. For more information see the section called “Configuring Transformer with XML”.

1.2.3 JMS Header Mapping

The DefaultJmsHeaderMapper now maps an incoming JMSPriority header to the Spring Integration priority header. Previously priority was only considered for outbound messages. For more information see Section 19.6, “Mapping Message Headers to/from JMS Message”.