Spring Boot 4.0.0 M1 Release Notes

Spring Boot 4.0.0-M1 Release Notes

Upgrading from Spring Boot 3.5

Migration Guide

To help with upgrading, a migration guide is available.

Minimum Requirements Changes

• Spring Framework 7

• Kotlin 2.2

New and Noteworthy

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

Milestones Available from Maven Central

Starting with 4.0.0-M1, Spring Boot milestones (and release candidates) are now published to Maven Central in addition to https://repo.spring.io.

Configuration Properties Metadata for External Types

It is now possible for @ConfigurationProperties-annotated types to refer to types that are located in a different module. To source the metadata from those modules, you should add the annotation processor (if necessary) and flag the type with @ConfigurationPropertiesSource.

See the reference documentation for more details.

SSL Info

Support for the certificate validity threshold has been removed from the SSL info contribution. A certificate that had a status of WILL_EXPIRE_SOON will now appear as VALID. The information about the start and end of a certificate’s validity remains.

SSL Health

Certificate chains that contain one or more certificates that will expire within the configured threshold (management.health.ssl.certificate-validity-warning-threshold) are now listed in a new expiringChains entry in the details of the health response. The status WILL_EXPIRE_SOON is no longer used and expiring certificates will have a status of VALID.

Task Decoration

The auto-configurations for task scheduling and task execution now support multiple TaskDecorator beans. When the context contains multiple TaskDecorator beans, a CompositeTaskDecorator that delegates to them is created. The individual decorators are called in the ordered defined by @Order and Ordered.

JmsClient

The auto-configuration for JMS now includes support for the new JmsClient API. The support for JmsTemplate and JmsMessagingTemplate is left unchanged.

Dependency Upgrades

Spring Boot 4.0.0-M1 moves to new versions of several Spring projects:

• Micrometer 1.16.0-M1

• Micrometer Tracing 1.6.0-M1

• Reactor 2025.0.0-M5

• Spring AMQP 4.0.0-M3

• Spring Authorization Server 2.0.0-M1

• Spring Batch 6.0.0-M1

• Spring Data 2025.1.0-M4

• Spring Framework 7.0.0-M7

• Spring GraphQL 2.0.0-M1

• Spring HATEOAS 3.0.0-M3

• Spring Integration 7.0.0-M1

• Spring Kafka 4.0.0-M3

• Spring LDAP 4.0.0-M1

• Spring Pulsar 2.0.0-M1

• Spring REST Docs 4.0.0-M1

• Spring Security 7.0.0-M1

• Spring Session 4.0.0-M1

• Spring WS 5.0.0-M1

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

• Brave 6.3

• Commons Codec 1.19

• Commons Lang 3.18

• Elasticsearch Client 9.0

• Flyway 11.10

• Hibernate 7.0

• Hibernate Validator 9.0

• HtmlUnit 4.13

• Jakarta Annotation 3.0

• Jakarta Persistence 3.2

• Jakarta Servlet 6.1

• Jakarta Validation 3.1

• Jakarta WebSocket 2.2

• Jakarta WS RS 4.0

• Jersey 4.0.0-M2

• Kafka 4.0

• Kotlin 2.2

• Kotlin Serialization 1.9

• Liquibase 4.33

• Mockito 5.18

• OpenTelemetry 1.52

• Pulsar Reactive 0.7

• Rabbit AMQP Client 5.26

• Selenium 4.34

• Selenium HtmlUnit 4.33

• Tomcat 11.0

Miscellaneous

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

• The auto-configuration for Micrometer’s metrics aspects now enables support for @MeterTag on @Counted and @Timed methods with a SpEL-based ValueExpressionResolver.

• @ServiceConnection support for MongoDB now supports Testcontainers' MongoDBAtlasLocalContainer

• Improved error message when configuration property binding fails due to a class not found error

• Names of several reactive auto-configuration classes have been updated for consistency

Deprecations in Spring Boot 4.0.0-M1

• OperationMethod(Method method, OperationType operationType) in favor of OperationMethod(Method method, OperationType operationType, Predicate<Parameter> optionalParameters)