What's New in Spring Framework 6.x

What's New in Version 6.2

Core Container

• Revised lifecycle phases and default timeouts; see 32152.
• Lenient locking in the core container; see 23501.
• Callback for singleton availability; see 21362.
• Faster component scanning for multiple scan operations through local root directory and jar caching; see 21190.
• Background initialization of specific beans via @Bean(bootstrap=BACKGROUND); see 13410 and 19487.
• Fast shortcut autowiring when parameter name (or @Qualifier value) matches bean name; see 28122 and 17677.
• Consistent generic type matching for nested/bounded/unresolvable type variables; see 30079, 22902 and 20727.
• Fallback bean definitions, with @Fallback as companion of @Primary; see 26241.
• Bean definitions with qualifier enforcement, based on defaultCandidate=false flag; see 26528.
• Support for escaping prefix and separator in property placeholders; see 9628.
• Consistent TaskDecorator support among TaskScheduler variants; see 23755.
• Consistent ErrorHandler support among TaskScheduler variants; see 32460.

Spring Expression Language (SpEL)

• Fully revised documentation for SpEL's property navigation and indexing support.
• Official documentation for indexing into strings and objects in SpEL expressions.
• First-class support for indexing into custom structures via new IndexAccessor and CompilableIndexAccessor SPIs plus a built-in ReflectiveIndexAccessor implementation of those SPIs; see related documentation.
• Safe navigation support for indexing into arrays, collections, strings, maps, objects, and custom structures; see related documentation.
• Improved compilation support for constructor and method invocations that use varargs as well as for expressions that index into arrays and lists with an Integer.
• Methods are now invoked via a public interface or public superclass whenever possible when compiling SpEL expressions.
• Class names generated by the SpEL compiler now take the form org.springframework.expression.spel.generated.CompiledExpression#####, where ##### is a 0-padded counter.

Data Access and Transactions

• Configurable default rollback rules, including rollbackOn attribute in @EnableTransactionManagement; see 23473.
• Type-level @Qualifier annotations as a hint for default transaction manager selection; see 24291.
• Savepoint callbacks on TransactionSynchronization; see 30509.
• Initial support for JPA 3.2; see 31157.
• Support for backticks for quoted SQL identifiers; see 31944 and 32285.
• Configuration of connection URL via EmbeddedDatabaseBuilder; see 21160.

Web Applications

• Interception of RFC-7807 responses; see 31822.
• Web support for YAML via Jackson; see 32345.
• Efficient webjars version resolution via webjars-locator-lite; see 27619.
• Optimized request predicate execution for router functions; see 32245.
• New URL parser implementation for UriComponentsBuilder etc.; see 32513.
• Support for content negotiation and view rendering in ResponseEntityExceptionHandler; see 31936 and reference documentation.
• FormHttpMessageConverter now supports single-value maps; see 32826.

Messaging Applications

• First-class virtual thread support for JMS DefaultMessageListenerContainer; see 32252.
• JMS DefaultMessageListenerContainer scales up as well as down with its default executor, based on revised idleReceivesPerTaskLimit semantics; see 32260.

Testing

• First-class mechanism for bean overriding in tests through @TestBean, @MockitoBean, and @MockitoSpyBean; see related documentation.
• Dynamic properties can now be registered from within a test's ApplicationContext; see related documentation.
  • The DynamicPropertyRegistry is now registered as a singleton bean in a test's ApplicationContext which allows it to be injected into @Configuration classes and @Bean methods.
  • @DynamicPropertySource can now optionally be applied to a @Bean method to signal that the corresponding bean should be eagerly initialized.
• Servlet 6.1 support in Spring's Servlet API mocks (while retaining Servlet 6.0 compatibility); see 31159.
• AssertJ support for MockMvc; see 21178.
• HtmlUnit 3.x/4.x support for MockMvc; see 30392.
• Improved JSONPath support; see 31651 and 31653.
• Testing support for WebMvc.fn; see 30477.

What's New in Version 6.1

Core Container

• General compatibility with virtual threads and JDK 21 overall.
• Configuration options for virtual threads: a dedicated VirtualThreadTaskExecutor and a virtual threads mode on SimpleAsyncTaskExecutor, plus an analogous SimpleAsyncTaskScheduler with a new-thread-per-task strategy and a virtual threads mode.
• Lifecycle integration with Project CRaC for JVM checkpoint restore (see related documentation), including a -Dspring.context.checkpoint=onRefresh option.
• Lifecycle integrated pause/resume capability and parallel graceful shutdown for ThreadPoolTaskExecutor and ThreadPoolTaskScheduler as well as SimpleAsyncTaskScheduler.
• A -Dspring.context.exit=onRefresh option is available with AppCDS training runs as the main use-case; see 31595.
• Reachability metadata contribution improvements, preparing for upcoming GraalVM changes: missing reachability metadata will be soon reported as runtime exceptions for better developer experience; see 31213.
• New ModuleResource: Resource implementation for java.lang.Module resolution, performing getInputStream() access via Module.getResourceAsStream.
• Custom @Component stereotype annotations may now use @AliasFor to configure an annotation attribute override for the component's name. Consequently, the name of the annotation attribute that is used to specify the bean name is no longer required to be value, and custom stereotype annotations can now declare an attribute with a different name (such as name) and annotate that attribute with @AliasFor(annotation = Component.class, attribute = "value").
• Convention-based @Component stereotype names based on the value attribute are now deprecated in favor of explicit @AliasFor declarations. See previous bullet point.
• Spring now finds all @ComponentScan and @PropertySource annotations; see 30941.
• Async/reactive destroy methods – for example, on R2DBC ConnectionFactory; see 26691.
• Async/reactive cacheable methods, including corresponding support in the Cache interface and in CaffeineCacheManager; see 17559 and 17920.
• Reactive @Scheduled methods (including Kotlin coroutines); see 22924.
• Selecting a specific target scheduler for each @Scheduled method; see 20818.
• @Scheduled methods for one-time tasks (with just an initial delay); see 31211.
• Observation instrumentation of @Scheduled methods; see 29883.
• Spring Framework will not produce observations out-of-the-box for @Async or @EventListener annotated methods, but will help you with propagating context (e.g. MDC logging with the current trace id) for the execution of those methods. See the new ContextPropagatingTaskDecorator, the relevant reference documentation section, and issue 31130.
• Validator factory methods for programmatic validator implementations; see 29890.
• Validator.validateObject(Object) with returned Errors and Errors.failOnError method for flexible programmatic usage; see 19877.
• MethodValidationInterceptor throws MethodValidationException subclass of ConstraintViolationException with violations adapted to MessageSource resolvable codes, and to Errors instances for @Valid arguments with cascaded violations; see 29825 and umbrella issue 30645.
• Support for resource patterns in @PropertySource; see 21325.
• Support for Iterable and MultiValueMap binding in BeanWrapper and DirectFieldAccessor; see 907 and 26297.
• Revised Instant and Duration parsing (aligned with Spring Boot); see 22013.
• Spring AOP now supports Kotlin Coroutines; see 22462.
• ControlFlowPointcut has been revised to make its internals more open to extension by subclasses.
• ControlFlowPointcut now provides built-in pattern matching support for method names, analogous to the pattern matching support in NameMatchMethodPointcut. Users can provide one or more method name patterns when constructing a ControlFlowPointcut. Alternatively, subclasses can override one of the new protected isMatch(...) methods – for example, to support regular expressions instead of simple pattern matching.
• New getMergedRepeatableAnnotationAttributes() method in AnnotatedTypeMetadata that provides dedicated support for finding merged repeatable annotation attributes with full @AliasFor semantics.

Spring Expression Language (SpEL)

• Numerous improvements to the SpEL Language Reference, including but not limited to:
  • Supported letters in variable names
  • Limitation regarding minimum values for numeric literals
  • Safe navigation support for selection and projection
  • Safe navigation semantics within compound expressions
  • Official documentation of the power operator, custom overloading operators, between operator, increment and decrement operators, as well as the repeat and character subtraction operators for strings
• Numerous bug fixes.
• Improved support for constructor and method invocations that use varargs.
• The maximum length of a SpEL expression used in an ApplicationContext is now configurable via the spring.context.expression.maxLength Spring property.
• Support for letters other than A-Z in property/field/variable names in SpEL expressions; see 30580.
• Support for registering a MethodHandle as a SpEL function; see related documentation.

Data Access and Transactions

• Common TransactionExecutionListener contract with beforeBegin/afterBegin, beforeCommit/afterCommit and beforeRollback/afterRollback callbacks triggered by the transaction manager (for thread-bound as well as reactive transactions); see 27479.
• @TransactionalEventListener and TransactionalApplicationListener always run in the original thread, independent from an async multicaster setup; see 30244.
• @TransactionalEventListener and TransactionalApplicationListener can participate in reactive transactions when the ApplicationEvent gets published with the transaction context as its event source; see 27515.
• A failed CompletableFuture triggers a rollback for an async transactional method; see 30018.
• DataAccessUtils provides various optionalResult methods with a java.util.Optional return type; see 27735.
• The new JdbcClient provides a unified facade for query/update statements on top of JdbcTemplate and NamedParameterJdbcTemplate, with flexible parameter options as well as flexible result retrieval options; see 30931.
• SimplePropertyRowMapper and SimplePropertySqlParameterSource strategies for use with JdbcTemplate/NamedParameterJdbcTemplate as well as JdbcClient, providing flexible constructor/property/field mapping for result objects and named parameter holders; see 26594.
• SimpleJdbcInsert now provides support for quoted identifiers which can be enabled via the new usingQuotedIdentifiers() builder method.
• SQLExceptionSubclassTranslator can be configured with an overriding customTranslator; see 24634.
• The R2DBC DatabaseClient provides bindValues(Map) for a pre-composed map of parameter values and bindProperties(Object) for parameter objects based on bean properties or record components; see 27282.
• The R2DBC DatabaseClient provides mapValue(Class) for plain database column values and mapProperties(Class) for result objects based on bean properties or record components; see 26021.
• BeanPropertyRowMapper and DataClassRowMapper available for R2DBC as well; see 30530.
• JpaTransactionManager with HibernateJpaDialect translates Hibernate commit/rollback exceptions to DataAccessException subclasses wherever possible, e.g. to CannotAcquireLockException, aligned with the exception hierarchy thrown from persistence exception translation for repository operations; see 31274 for the primary motivation.

Web Applications

• Spring MVC and WebFlux now have built-in method validation support for controller method parameters with @Constraint annotations. That means you no longer need @Validated at the controller class level to enable method validation via an AOP proxy. Built-in method validation is layered on top of the existing argument validation for model attribute and request body arguments. The two are more tightly integrated and coordinated, e.g. avoiding cases with double validation. See Upgrading to 6.1 for migration details and umbrella issue 30645 for all related tasks and feedback.
• Method validation is supported with method parameters that are collections, arrays, or maps of objects.
• The HandlerMethodValidationException raised by the new built-in method validation exposes a Visitor API to process validation errors by controller method parameter type, e.g. @RequestParameter, @PathVariable, etc.
• MethodValidationInterceptor supports validation of Mono and Flux method parameters; see issue 20781.
• Spring MVC raises NoHandlerFoundException by default if there is no matching handler or ResponseStatusException(NOT_FOUND) if there is no matching static resource, and also handles these with the aim of consistent handling for 404 errors out of the box, including RFC 7807 responses; see 29491.
• ErrorResponse allows customization of ProblemDetail type via MessageSource and use of custom ProblemDetail through its builder.
• Spring MVC resets the Servlet response buffer prior to handling an error and rendering an error response.
• DataBinder now supports constructor binding where argument values are looked up through a NameResolver (e.g. in the HTTP request parameters map), and those lookups can be customized through an @BindParam annotation. This also supports nested object structures through the invocation of constructors necessary to initialize constructor parameters. The feature is integrated in the data binding of Spring MVC and WebFlux and provides a safer option for data binding of expected parameters only; see Model Design for more details. Spring MVC and WebFlux now support data binding via constructors, including nested objects constructors
• @ControllerAdvice and @RestControllerAdvice can now specify custom component names via their new name attributes.
• WebFlux provides an option for blocking execution of controller methods with synchronous signatures on a different Executor such as the VirtualThreadTaskExecutor; see Blocking Execution in the reference documentation.
• SseEmitter now formats data with newlines according to the SSE format.
• New RestClient, a synchronous HTTP client that offers an API similar to WebClient, but sharing infrastructure with the RestTemplate; see 29552.
• Jetty-based ClientHttpRequestFactory for use with RestTemplate and RestClient; see 30564.
• JDK HttpClient-based ClientHttpRequestFactory for use with RestTemplate and RestClient; see 30478.
• Reactor Netty-based ClientHttpRequestFactory for use with RestTemplate and RestClient; see 30835.
• Improved buffering in various ClientHttpRequestFactory implementations; see 30557.
• HTTP Interface client with built-in adapters for the new RestClient and RestTemplate in addition to the existing adapter for the reactive WebClient.
• HTTP Interface client supports MultipartFile as an input method parameter.
• HTTP Interface client supports UriBuilderFactory as an input method parameter to use instead of the one the underlying client is configured with – for example, if it's necessary to vary the baseUri dynamically.
• The @HttpExchange annotation used on HTTP interface methods is now supported for server-side handling in Spring MVC and WebFlux as an alternative to @RequestMapping; see @HttpExchange for more details and guidance.
• JVM checkpoint restore support added to Reactor Netty-based ClientHttpRequestFactory for use with RestTemplate and RestClient and to ClientHttpConnector for use with WebClient; see 31280, 31281, and 31180.
• General Coroutines support revision in WebFlux, which includes CoroutineContext propagation in CoWebFilter, CoroutineContext propagation in coRouter DSL with filter, a new context function in coRouter DSL, support for @ModelAttribute with suspending function in WebFlux, and consistent usage of the Mono variant of awaitSingle().
• Support for Kotlin parameter default and optional values in HTTP handler methods; see 21139 and 29820.

Messaging Applications

• STOMP messaging supports a new preserveReceiveOrder config option for ordered processing of messages received from a given client. That's in addition to the existing preservePublishOrder flag for messages published to clients; see the Order of Messages section of the reference docs.
• The @RSocketExchange annotation used on RSocket interface methods is now supported for responder-side handling as an alternative to @MessageMapping; see @RSocketExchange for more details and guidance.
• Interface parameter annotations are detected for messaging handler methods as well (analogous to web handler methods).
• The SpEL-based selector header support in WebSocket messaging is now disabled by default and must be explicitly enabled; see 30550 and Upgrading to 6.1 for migration details.
• Observability support for JMS: Spring Framework now produces observations when publishing messages with JmsTemplate and when processing messages with MessageListener or @JmsListener; see the reference docs section and issue 30335.

Testing

• ApplicationContext failure threshold support: avoids repeated attempts to load a failing ApplicationContext in the TestContext framework, based on a failure threshold which defaults to 1 but can be configured via a system property; see related documentation.
• @⁠SpringJUnitConfig and @⁠SpringJUnitWebConfig now declare loader attributes that support custom ContextLoader configuration.
• A ContextCustomizerFactory can now be registered for a particular test class via the new @ContextCustomizerFactories annotation.
• Numerous enhancments for @TestPropertySource:
  • Support for resource patterns (i.e., wildcards) in locations.
  • Multiple inlined properties can be supplied via a single text block.
  • Property file encoding can be configured via the new encoding attribute.
  • A custom PropertySourceFactory can be configured via the new factory attribute in order to support custom property file formats such as JSON, YAML, etc.
• Support for recording asynchronous events with @RecordApplicationEvents; see 30020.
  • Record events from threads other than the main test thread.
  • Assert events from a separate thread – for example with Awaitility.
• When used with JUnit Jupiter, @​BeforeTransaction and @​AfterTransaction methods can now make use of parameter injection to have Spring components (such as an @Autowired DataSource) injected directly into the method.
• JdbcTestUtils has new overloaded methods that accept a JdbcClient instead of JdbcOperations.
• MockMvc now supports initialization of filters with init parameters and mapping to specific dispatch types.
• MockMvcWebTestClient now supports the RequestPostProcessor hook which can, for example, allow varying user identity across tests; see 31298.
• MockRestServiceServer supports the new RestClient in addition to the RestTemplate.
• Support for null in MockHttpServletResponse.setCharacterEncoding(); see 30341.
• Errors encountered during build-time AOT processing now cause the build to fail immediately. This behavior can be disabled by setting the spring.test.aot.processing.failOnError property to false. See Upgrading to 6.1 for migration details.
• New @⁠DisabledInAotMode annotation that can be used to disable AOT build-time processing of a test's ApplicationContext and to disable an entire test class or a single test method at run time when the test suite is run with AOT optimizations enabled.
• @Resource may now be used for dependency injection in test classes when running in AOT mode.

What's New in Version 6.0

JDK 17+ and Jakarta EE 9+ Baseline

• Entire framework codebase based on Java 17 source code level now.
• Migration from javax to jakarta namespace for Servlet, JPA, etc.
• Runtime compatibility with Jakarta EE 9 as well as Jakarta EE 10 APIs.
• Compatible with latest web servers: Tomcat 10.1, Jetty 11, Undertow 2.3.
• Early compatibility with virtual threads (in preview as of JDK 19).

General Core Revision

• Upgrade to ASM 9.4 and Kotlin 1.7.
• Complete CGLIB fork with support for capturing CGLIB-generated classes.
• Comprehensive foundation for Ahead-Of-Time transformations.
• First-class support for GraalVM native images (see related Spring Boot 3 blog post).

Core Container

• Basic bean property determination without java.beans.Introspector by default.
• AOT processing support in GenericApplicationContext (refreshForAotProcessing).
• Bean definition transformation based on pre-resolved constructors and factory methods.
• Support for early proxy class determination for AOP proxies and configuration classes.
• PathMatchingResourcePatternResolver uses NIO and module path APIs for scanning, enabling support for classpath scanning within a GraalVM native image and within the Java module path, respectively.
• DefaultFormattingConversionService supports ISO-based default java.time type parsing.

Data Access and Transactions

• Support for predetermining JPA managed types (for inclusion in AOT processing).
• JPA support for Hibernate ORM 6.1 (retaining compatibility with Hibernate ORM 5.6).
• Upgrade to R2DBC 1.0 (including R2DBC transaction definitions).
• Aligned data access exception translation between JDBC, R2DBC, JPA and Hibernate.
• Removal of JCA CCI support.

Spring Messaging

• RSocket interface client based on @RSocketExchange service interfaces.
• Early support for Reactor Netty 2 based on Netty 5 alpha.
• Support for Jakarta WebSocket 2.1 and its standard WebSocket protocol upgrade mechanism.

General Web Revision

• HTTP interface client based on @HttpExchange service interfaces.
• Support for RFC 7807 problem details.
• Unified HTTP status code handling.
• Support for Jackson 2.14.
• Alignment with Servlet 6.0 (while retaining runtime compatibility with Servlet 5.0).

Spring MVC

• PathPatternParser used by default (with the ability to opt into PathMatcher).
• Removal of outdated Tiles and FreeMarker JSP support.

Spring WebFlux

• New PartEvent API to stream multipart form uploads (both on client and server).
• New ResponseEntityExceptionHandler to customize WebFlux exceptions and render RFC 7807 error responses.
• Flux return values for non-streaming media types (no longer collected to List before written).
• Early support for Reactor Netty 2 based on Netty 5 alpha.
• JDK HttpClient integrated with WebClient.

Observability

Direct Observability instrumentation with Micrometer Observation in several parts of the Spring Framework. The spring-web module now requires io.micrometer:micrometer-observation:1.10+ as a compile dependency.

• RestTemplate and WebClient are instrumented to produce HTTP client request observations.
• Spring MVC can be instrumented for HTTP server observations using the new org.springframework.web.filter.ServerHttpObservationFilter.
• Spring WebFlux can be instrumented for HTTP server observations using the new org.springframework.web.filter.reactive.ServerHttpObservationFilter.
• Integration with Micrometer Context Propagation for Flux and Mono return values from controller methods.

Testing

• Support for testing AOT-processed application contexts on the JVM or within a GraalVM native image.
• Integration with HtmlUnit 2.64+ request parameter handling.
• Servlet mocks (MockHttpServletRequest, MockHttpSession) are based on Servlet API 6.0 now.
• New MockHttpServletRequestBuilder.setRemoteAddress() method.
• The four abstract base test classes for JUnit 4 and TestNG no longer declare listeners via @TestExecutionListeners and instead now rely on registration of default listeners.