[PHJ2000]

Deprecate the Paho-based spring-integration-mqtt types for removal as of 7.2 in favor of the HiveMQ-based spring-integration-mqtt-client module. Update the MQTT reference and What's New with the deprecation and migration direction. No runtime logic is changed.

Fixes #11538.

Validation

• :spring-integration-mqtt:check api antora: passed after updating the branch to main at 6a037f85a8 (50 MQTT tests passed, zero failures/skips; Checkstyle, API docs, and reference docs passed; JDK 25 and Docker).
• The full test suite has not completed successfully locally. JDBC testing on unmodified main also exhibits repeated MySqlTxTimeoutMessageStoreTests.concurrentPolling timeouts, reported in MySqlTxTimeoutMessageStoreTests.concurrentPolling repeatedly times out during JDBC module tests #11553. In a separate observation, two attempts reached the existing 10-minute JUnit timeout and advanced to retries; the run was stopped by my 30-minute observation limit before all retries completed. This is not a claim of a permanent hang or a final suite failure.

Proposed migration guide note

The wiki is maintained separately from this repository. Could the following note be included in the 7.1-to-7.2 migration guide?

Paho-based MQTT support

The spring-integration-mqtt module and its types are deprecated for removal in Spring Integration 7.2.
Use the spring-integration-mqtt-client module, which is based on the HiveMQ MQTT client, for new MQTT integrations.

When migrating an existing integration, replace the org.springframework.integration:spring-integration-mqtt dependency with org.springframework.integration:spring-integration-mqtt-client.
Update the Spring Integration MQTT components to use the org.springframework.integration.mqtt.client packages and adapt client configuration to the HiveMQ API.
For example, the new module provides Mqtt3ClientManager and Mqtt5ClientManager instead of Mqttv3ClientManager and Mqttv5ClientManager, and Mqtt3MessageDrivenChannelAdapter and Mqtt5MessageDrivenChannelAdapter for inbound adapters.
Paho connection options and callback implementations need to be adapted to the corresponding HiveMQ APIs.

The deprecated module remains available in 7.2.

[artembilan]

The Migration Guide note is done: https://github.com/spring-projects/spring-integration/wiki/Spring-Integration-7.1-to-7.2-Migration-Guide

[artembilan]

Thank you!

A little inconvenience, though.
Now we got a gazillion of removal warnings in our build logs.
Please, go over all the classes in the module (including tests) and add a @SuppressWarnings("removal"), too.
This will mitigate build noise on the matter and won't cause a situation that some other problem would slip from us.

[artembilan]

I don't think it makes sense to put such an annotation on all the inner types.
I believe just top-level class is enough.

[PHJ2000]

Removed the redundant @Deprecated annotations and @deprecated Javadoc tags from ConnectCallback, DefaultMessageHandler, and Will in 02b7ee2. Deprecation is now declared only on the enclosing top-level types.

[PHJ2000]

Addressed in 02b7ee2.

Added @SuppressWarnings("removal") to all top-level types in the module, including test classes, while preserving existing warning suppressions. Removed the redundant deprecation annotations and Javadoc tags from nested types, as noted in the inline thread.

Validation: :spring-integration-mqtt:check api with --no-build-cache passed on JDK 25. All 50 MQTT tests passed with no failures or skips; Checkstyle and API documentation generation passed, and the build log contains no removal warnings. The full project test suite was not rerun for this annotation-only follow-up.

Thank you for adding the migration guide note.