What’s New in Spring Framework 5.3? Key Features and Upgrade Benefits

On October 27, the Spring Framework team announced the official GA of version 5.3, which is now available on repo.spring.io and Maven Central.

JDK version support

Spring Framework 5.3 requires JDK 8 or higher and adds explicit support for JDK 15. As the final feature branch of the 5.x line, future releases will continue to extend support to newer JDK versions, including JDK 17 LTS.

Spring Boot version support

Spring Boot 2.4 and the upcoming Spring Boot 2.5 will be based on this version.

Key updates

spring-r2dbc module adds core R2DBC support as the foundation for Spring Data R2DBC and introduces JdbcTemplate query result streaming.

Performance improvements for PathPattern parsing in Spring MVC.

Unified API for MockMvc with full HTTP testing and a revised Kotlin DSL.

WebFlux now includes a fully reactive multipart request body reader and an Apache HttpComponents 5 WebClient connector.

Kotlin Multiplatform serialization support for JSON payloads in Web and messaging endpoints, plus new RSocketClient and load‑balancing support for RSocket 1.1.

For a complete list of changes, see the official GitHub wiki.

Why upgrade?

Spring Framework 5.3 is the recommended upgrade for all 5.x and 4.x users. It is a long‑term maintenance release with support through 2024, whereas the previous 4.3.x line ends maintenance in December 2020.