Spring Boot 4.1.0 RC1 Release Notes

Spring Boot 4.1.0-RC1 Release Notes

For changes in earlier milestones, please refer to:

• v4.1.0-M4

• v4.1.0-M3

• v4.1.0-M2

• v4.1.0-M1

Upgrading from Spring Boot 4.0

New and Noteworthy

Tip	Check the configuration changelog for a complete overview of the changes in configuration.

Load Layers Configuration from the Classpath with Maven

It is now possible to load the layers configuration that the Maven plugin should use to repackage the application. Custom layers should be placed in META-INF/spring/layers/<name>.xml and added as a plugin’s dependency.

Review the documentation for more details.

OpenTelemetry Support

Support has been added to read most of the OpenTelemetry environment variables (for example those, those, and those).

A complete list of all supported variables and their corresponding Spring Boot configuration property can be found in the documentation.

Dependency Upgrades

Spring Boot 4.1.0-RC1 moves to new versions of several Spring projects:

• …​

Numerous third-party dependencies have been updated, some of the more noteworthy of which are the following:

• …​

Miscellaneous

Apart from the changes listed above, there have also been lots of minor tweaks and improvements including:

• Application-wide HTML escaping configuration for webflux can be configured using spring.webflux.default-html-escape.

Deprecations in Spring Boot 4.1.0-RC1

• None.