Spring Boot 2.3.3 Released with JDK 15 Support, New Features and 67 Bugfixes

Spring Boot 2.3.3 stable version is now available and can be obtained from repo.spring.io or Maven Central.

The release includes a total of 67 bug fixes, feature enhancements, documentation improvements, and dependency upgrades.

New Features

Applying HTTP/2 in Spring Boot no longer requires a forced Jetty and Conscrypt binding (issue #22188).

Bugfixes

Fixed externalized configuration ignoring null values in SPRING_APPLICATION_JSON (issue #22895).

Fixed migration issues for legacy endpoint IDs containing a hyphen (issue #22849).

Ensured that the cause of Reactor debug agent initialization failures is no longer discarded (issue #22847).

Resolved OCI image build failures when the environment contains empty properties (issue #22703).

Fixed LiquibaseEndpoint not reporting changesets from ancestor contexts (issue #22686).

Corrected 404 responses caused by requests that should be handled by another DispatcherServlet (issue #22682).

Addressed asynchronous exception handling failures for pages deployed as WAR (issue #22672).

Fixed incompatibility of XADataSourceAutoConfiguration with DB2XADataSource due to missing URL property (issue #22641).

Adjusted TaskExecutorBuilder to use second‑level precision when configuring shutdown wait periods (issue #22611).

Resolved the problem where setting ignoreInvalidFields=true on @ConfigurationProperties caused unknown fields to be ignored (issue #22585).

Ensured a new application context is created for each integration test class when using @SpyBean (issue #22583).

Fixed silent removal of Kotlin detection warnings in Jackson2ObjectMapperBuilder during backend pre‑initialization (issue #22580).

Corrected UndertowWebServerFactoryCustomizer to support UndertowOptions instead of only Options (issue #22578).

Ensured WebMvcTest and WebFluxTest import the necessary Jackson module beans (issue #22576).

Allowed CouchbaseCacheManager to be customized via CacheManagerCustomizer (issue #22573).

Fixed Kubernetes readiness probe endpoint returning 404 (issue #22562).

Corrected ordering issues in CouchbaseCacheConfiguration (issue #22542).

Resolved a Mustache environment collector failure when using the nullValue compiler option in 2.3.1 (issue #22039).

In addition, many dependencies have been upgraded and the documentation has been improved. For full details, see the official release page:

https://github.com/spring-projects/spring-boot/releases/tag/v2.3.3.RELEASE