Spring Boot 3.0.0 RC2 Release Notes

For changes in earlier milestones, please refer to:

Upgrading from Spring Boot 2.x

Jakarta EE 10

Following the end of life announcement for Apache Tomcat 10.0, we have upgraded from Jakarta EE 9 to Jakarta EE 10. Where Spring Boot depends upon a Jakarta EE specification, we now use the version that is included in Jakarta EE 10. For example, Spring Boot 3.0 uses the Servlet 6.0 and JPA 3.1 specifications by default. Jakarta EE 9 is still supported and a war-packaged Spring Boot application can be deployed to an EE 9 environment.

Jetty

Jetty does not yet support Servlet 6.0. To use Jetty with Spring Boot 3.0, you will have to downgrade the Servlet API to 5.0. You can use the jakarta-servlet.version property to do so.

Dependency Management for Hazelcast Hibernate Removed

Spring Boot does not depend on Hazelcast Hibernate so it need not have an opinion about its version. As such, dependency management for Hazelcast Hibernate has been removed. If you wish to continue using Hazelcast Hibernate, specify a version that meets your needs. Alternatively, consider using org.hibernate.orm:hibernate-jcache instead.

`httptrace` Endpoint Renamed to `httpexchanges`

The httptrace endpoint and related infrastructure records and provides access to information about recent HTTP request-response exchanges. Following the introduction of support for Micrometer Tracing, the name httptrace may cause confusion. To reduce this possible confusion the endpoint has been renamed to httpexchanges. The contents of the endpoint’s response has also been affected by this renaming. Please refer to the Actuator API documentation for further details.

Related infrastructure classes have also been renamed. For example, HttpTraceRepository is now named HttpExchangeRepository and can be found in the org.springframework.boot.actuate.web.exchanges package.

Actuator JSON

Responses from the actuator endpoints shipped with Spring Boot now use an isolated ObjectMapper instance to ensure results are consistent. If you want to revert to the old behavior and use the application ObjectMapper you can set management.endpoints.jackson.isolated-object-mapper to false.

If you have developed your own endpoints, you might want to ensure that responses implement the OperationResponseBody interface. This will ensure that the isolated ObjectMapper is considered when serializing the response as JSON.

Micrometer Metrics and Spring Cloud Sleuth Traces

If your project is using metrics or traces, please refer to the dedicated page for Spring Boot Metrics 3.0.

New and Noteworthy

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

GraalVM

Spring Boot now requires Graal 22.3 or later and Native Build Tools Plugin 0.9.17 or later

Dependency Upgrades

Spring Boot 3.0.0-RC2 moves to new versions of several Spring projects:

Spring Batch 5.0.0-RC2
Spring Data 2022.0.0-RC2
Spring Framework 6.0.0-RC4
Spring Integration 6.0.0-RC2
Spring Kafka 3.0.0-RC2
Spring Security 6.0.0-RC2
Spring Session 3.0.0-RC2

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

Couchbase Client 3.4
Elasticsearch Client 8.5
Glassfish JAXB 4.0
Glassfish JSTL 3.0
Hibernate Validator 8.0
Jackson 2.14
Jakarta Activation 2.1
Jakarta Json 2.1
Jakarta Json Bind 3.0
Jakarta Mail 2.1
Jakarta Persistence 3.1
Jakarta Servlet 6.0
Jakarta Servlet JSP JSTL 3.0
Jakarta XML Bind 4.0
Jakarta XML SOAP 3.0
Jakarta XML WS 4.0
Jakarta WebSocket 2.1
Jakarta WS RS 3.1
Jersey 3.1
Micrometer 1.10
Micrometer Tracing 1.0
Neo4j Java Driver 5.2
Reactor 2022.0
SAAJ Implements 3.0
Tomcat 10.1
Undertow 2.3
Yasson 3.0

Miscellaneous

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

SpanCustomizer beans for Brave and OpenTelemetry are now auto-configured.
Host names are no longer logged during application startup. This prevents a network lookup which helps improve startup times.
Bean implementing the MeterBinder interface are now bound to meter registries only after all singleton beans have been initialized.