For those who are already familiar with Spring Integration, this chapter provides a brief overview of the new features of version 5.2.

If you are interested in the changes and features that were introduced in earlier versions, see the Change History.

What’s New in Spring Integration 5.2?

If you are interested in more details, see the Issue Tracker tickets that were resolved as part of the 5.2 development process.

Also see a new Reactive Streams Support chapter in this documentation.

Package and Class Changes

Pausable has been moved from o.s.i.endpoint to o.s.i.core.

Behavior Changes

See the Migration Guide about behavior changes in this version.

New Components

RSocket Support

The spring-integration-rsocket module is now available with channel adapter implementations for RSocket protocol support. See RSocket Support for more information.

Rate Limit Advice Support

The RateLimiterRequestHandlerAdvice is now available for limiting requests rate on handlers. See Rate Limiter Advice for more information.

Caching Advice Support

The CacheRequestHandlerAdvice is now available for caching request results on handlers. See Caching Advice for more information.

Kotlin Scripts Support

The JSR223 scripting module now includes a support for Kotlin scripts. See Scripting Support for more information.

Flux Aggregator Support

The FluxAggregatorMessageHandler is now available for grouping and windowing messages logic based on the Project Reactor Flux operators. See Flux Aggregator for more information.

FTP/SFTP Event Publisher

The FTP and SFTP modules now provide an event listener for certain Apache Mina FTP/SFTP server events. See Apache Mina FTP Server Events and Apache Mina SFTP Server Events for more information.

Avro Transformers

Simple Apache Avro transformers are now provided. See Avro Transformers for more information.

General Changes

The JsonToObjectTransformer now supports generics for the target object to deserialize into. See JSON Transformers for more information.

The splitter now supports a discardChannel configuration option. See Splitter for more information.

The Control Bus can now handle Pausable (extension of Lifecycle) operations. See Control Bus for more information.

The Function<MessageGroup, Map<String, Object>> strategy has been introduced for the aggregator component to merge and compute headers for output messages. See Aggregator Programming Model for more information.

All the MessageHandlingException s thrown in the framework, includes now a bean resource and source for back tracking a configuration part in case no end-user code involved. See Error Handling for more information.

For better end-user experience, Java DSL now provides a configurer variant for starting flow with a gateway interface. See IntegrationFlows.from(Class<?> serviceInterface, Consumer<GatewayProxySpec> endpointConfigurer) JavaDocs for more information. Also a MethodArgsHolder is now a root object for evaluation context for all the expressions in the GatewayProxyFactoryBean. The #args and #method evaluation context variables are now deprecated. See Messaging Gateways for more information.

AMQP Changes

The outbound endpoints can now be configured to synthesize a "nack" if no publisher confirm is received within a timeout. See Outbound Channel Adapter for more information.

The inbound channel adapter can now receive batched messages as a List<?> payload instead of receiving a discrete message for each batch fragment. See Batched Messages for more information.

The outbound channel adapter can now be configured to block the calling thread until a publisher confirm (acknowledgment) is received. See Outbound Channel Adapter for more information.

File Changes

Some improvements to filtering remote files have been made. See Remote Persistent File List Filters for more information.

TCP Changes

The length header used by the ByteArrayLengthHeaderSerializer can now include the length of the header in addition to the payload. See Message Demarcation (Serializers and Deserializers) for more information.

When using a TcpNioServerConnectionFactory, priority is now given to accepting new connections over reading from existing connections, but it is configurable. See About Non-blocking I/O (NIO) for more information.

The outbound gateway has a new property closeStreamAfterSend; when used with a new connection for each request/reply it signals EOF to the server, without closing the connection. This is useful for servers that use the EOF to signal end of message instead of some delimiter in the data. See TCP Gateways for more information.

The client connection factories now support connectTimeout which causes an exception to be thrown if the connection is not established in that time. See TCP Connection Factories for more information.

SoftEndOfStreamException is now a RuntimeException instead of extending IOException.

Mail Changes

The AbstractMailReceiver has now an autoCloseFolder option (true by default), to disable an automatic folder close after a fetch, but populate IntegrationMessageHeaderAccessor.CLOSEABLE_RESOURCE header instead for downstream interaction. See Mail-receiving Channel Adapter for more information.

HTTP Changes

The HTTP inbound endpoint now support a request payload validation. See HTTP Support for more information.

WebFlux Changes

The WebFluxRequestExecutingMessageHandler now supports a Publisher, Resource and MultiValueMap as a request message payload. The WebFluxInboundEndpoint now supports a request payload validation. See WebFlux Support for more information.

MongoDb Changes

The MongoDbMessageStore can now be configured with custom converters. See MongoDB Support for more information.

Router Changes

You can now disable falling back to the channel key as the channel bean name. See Dynamic Routers for more information.

FTP/SFTP Changes

The RotatingServerAdvice is decoupled now from the RotationPolicy and its StandardRotationPolicy.

The remote file information, including host/port and directory are included now into message headers in the AbstractInboundFileSynchronizingMessageSource and AbstractRemoteFileStreamingMessageSource implementations. Also this information is included into headers in the read operations results of the AbstractRemoteFileOutboundGateway implementations. The FTP outbound endpoints now support chmod to change permissions on the uploaded file. (SFTP already supported it since version 4.3). See FTP(S) Support and SFTP Support for more information.