Hi, Spring fans! Welcome to yet another installment of This Week in Spring! It's October 17th, 2023, and I am here in Montreal, Canada, and then I'm off to Salt Lake City, Utah on Thursday for the Java User Group there. Don't miss it!

We've got a lot to cover this week so let's dive right into it!

• Apache Kafka's Exactly-Once Semantics in Spring Cloud Stream Kafka Applications
• Guide to Modulith with Spring Boot - Piotr's TechBlog
• Runtime efficiency with Spring (today and tomorrow)
• Spring Data 2023.0.5, 2022.0.11, and 2021.2.17 released
• Spring Framework 6.0.13 available now
• Transactional Rollback Strategies with Spring Cloud Stream and Apache Kafka
• Using Records as Projections in JPA
…

On behalf of the team and everyone who has contributed, I’m happy to announce that Spring Cloud Dataflow 2.11.1 has been released and is now available from Maven Central.

Notable Changes in 2.11.1

• Updated versions and mitigations for CVEs.
  • json-smart: 2.4.11
  • nimbus-jose-jwt: 9.31
  • snappy-java: 1.1.10.4
  • commons-compress: 1.24.0
• Ensure TaskOperations launch API is backwards compatible.
• Fix issues in dependency managements of modules after creating mono-repo.

Library Updates

• Spring Boot 2.7.16

See the release notes for more information.

Stay in touch...

As always, we welcome feedback and contributions, so please reach out to us on Stackoverflow or GitHub…

Other parts in this blog series

Part 1: Introduction to Transactions in Spring Cloud Stream Kafka Applications

Part 2: Producer Initiated Transactions in Spring Cloud Stream Kafka Applications

Part 3: Synchronizing with External Transaction Managers in Spring Cloud Stream Kafka Applications

Part 4: Transactional Rollback Strategies with Spring Cloud Stream and Apache Kafka

With the fundamental analysis of how transactions work with Spring Cloud Stream Kafka applications out of the way from our previous discussions in this series, we have finally arrived at the elephant in the room: the exactly-once semantics, a much-discussed and required feature in streaming applications. In this part of this blog series, we look at how you can get exactly-once semantics in Spring Cloud Stream applications via Apache Kafka transactions. The knowledge of how transactions work from the previous sections makes it relatively easy to understand how Spring Cloud Stream Kafka applications achieve…

With Spring Framework 6.1 and Spring Boot 3.2 general availability approaching, we would like to share an overview about several efforts the Spring team is pursuing to allow developers to optimize the runtime efficiency of their applications.

We are going to cover the following technologies and use cases:

• Spring MVC as a lean Virtual Threads web stack on JDK 21
• Optimized container deployment with Spring and GraalVM Native Image
• JVM Checkpoint Restore: Scale to zero with Spring and Project CRaC
• A glimpse into OpenJDK’s future with Spring AOT and Project Leyden

If you prefer watching a video…

On behalf of the team and everyone who has contributed, I’m pleased to announce the availability of 2023.0.5, 2022.0.11, and 2021.2.17 service releases. These releases ship with dependency upgrades, fixes and improvements.

The upcoming Spring Boot releases 3.1.5, respective 3.0.12 and 2.7.17 will pick up the above releases by next week.

We expect the next set of Spring Data maintenance releases to ship in mid-November, along with the new and exciting 3.2 we have been working on the last few months.

2023.0.5

• Spring Data Commons 3.1.5 - Javadoc - Documentation - Changelog
• Spring Data JPA 3.1.5 - Javadoc - Documentation - Changelog
• Spring Data Neo4j 7.1.5 - Javadoc - Documentation - Changelog
• Spring Data for Apache Cassandra 4.1.5 - Javadoc - Documentation - Changelog
• Spring Data MongoDB 4.1.5 - Javadoc - Documentation - Changelog
• Spring Data KeyValue 3.1.5 - Javadoc - Documentation - Changelog
• Spring Data LDAP 3.1.5 - Javadoc - Documentation - Changelog
• Spring Data REST 4.1.5 - Javadoc - Documentation - Changelog
• Spring Data Redis 3.1.5 - Javadoc - Documentation - Changelog
• Spring Data Elasticsearch 5.1.5 - Javadoc - Documentation - …

Spring Shell 3.2.0-M2 is now available

On behalf of the team and everyone who has contributed, I'm happy to announce that Spring Shell 3.2.0-M2 is now available from Spring repos.

This release is adding first experimental support for Terminal UI as shown in a below screencast:

Please see the release notes 3.2.0-M2 for more details.

Thanks to all those who have contributed with issue reports and pull requests.

How can you help?

Project Page | GitHub | Issues | Documentation

It is my pleasure to announce that a feature-complete Spring Data 2023.1 release candidate is available now! This release is in preparation for a first Spring Boot 3.2 release candidate next week. We expect final releases for general availability in November.

This RC ships a couple of New and Noteworthy changes:

• @ReadPreference support for Repository Query Methods and support for dots in MongoDB document field names.
• Revision of the Converter arrangement in Spring Data Relational allowing to use the same converter abstraction for JDBC and R2DBC modules.
• Asynchronous Caching support for Redis when using the Lettuce driver.
…

On behalf of the team and everyone who has contributed, I am pleased to announce that Spring Framework 6.0.13 is available now.

Spring Framework 6.0.13 ships with 34 fixes and documentation improvements, including 7 fixes for regressions. This version will be shipped with Spring Boot 3.0.12 and 3.1.5, to be released next week.

We expect the next set of Spring Framework maintenance releases to ship next November, along with the new and exciting 6.1.0 we have been working on the last few months.

Project Page | GitHub | Issues | Documentation

On behalf of the Spring Framework team, it is my pleasure to announce that the first Spring Framework 6.1 release candidate is available from repo.spring.io/milestone now.

Spring Framework 6.1.0-RC1 ships 75 fixes and improvements.

New Features

This first release candidate ships a few new features:

• Spring Framework 6.1 requires now a Jackson 2.14 baseline and supports the new DatatypeFeature
• We have made further AOT improvements, reduced the runtime reflection and prepared Framework for upcoming reachability changes in GraalVM
• You can now use an OutputStream as a source of data in reactive web APIs, thanks to a new BodyInserter method variant
• Functional web frameworks now allow headers manipulation when serving static resources; this makes it easier to write HTTP caching response headers.
…