Auto-configuration Classes Reference for Spring Boot

Spring Boot’s auto-configuration system is the engine behind convention-over-configuration: it inspects the libraries on your classpath, the beans already defined in your application context, and a set of environment properties, then automatically registers exactly the infrastructure beans your application needs — without requiring any explicit @Bean declarations from you. Understanding how this mechanism works lets you extend it, override it, and debug it when something does not behave as expected.

How auto-configuration works

Auto-configuration classes are regular @Configuration classes annotated with @AutoConfiguration. Spring Boot discovers them at startup by reading every META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports file found on the classpath. Each line in that file is a fully-qualified class name of an auto-configuration class to consider.

META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports

org.springframework.boot.jdbc.autoconfigure.DataSourceAutoConfiguration
org.springframework.boot.jdbc.autoconfigure.JdbcTemplateAutoConfiguration
org.springframework.boot.hibernate.autoconfigure.HibernateJpaAutoConfiguration

To see which auto-configurations are active (or inactive, and why), start your application with --debug or -Ddebug=true. The conditions report printed to the log shows every auto-configuration class, which conditions passed, and which conditions caused it to be skipped. In an Actuator application, you can also query the /actuator/conditions endpoint at runtime.

The `@AutoConfiguration` annotation

@AutoConfiguration is a composed annotation that combines @Configuration(proxyBeanMethods = false) with auto-configuration-specific metadata. Disabling CGLIB proxying is the default because auto-configuration classes are typically infrastructure configuration that does not need full proxy semantics.

@AutoConfiguration(after = DataSourceAutoConfiguration.class)
@ConditionalOnClass({ DataSource.class, JdbcTemplate.class })
@ConditionalOnSingleCandidate(DataSource.class)
public class JdbcTemplateAutoConfiguration {

    @Bean
    @ConditionalOnMissingBean(JdbcOperations.class)
    JdbcTemplate jdbcTemplate(DataSource dataSource, JdbcProperties properties) {
        // ...
    }
}

Ordering auto-configurations

Auto-configurations can declare ordering constraints to ensure that one configuration runs before or after another:

@AutoConfiguration(after = X.class) — equivalent to @AutoConfigureAfter. Ensures this class is processed after X.
@AutoConfiguration(before = X.class) — equivalent to @AutoConfigureBefore. Ensures this class is processed before X.

Ordering only determines the order in which Spring evaluates conditions, not the order in which beans are instantiated at runtime. For runtime ordering, use @DependsOn or @Order on the beans themselves.

Conditional annotations

Auto-configurations use conditional annotations to activate only when the right conditions are met. Stacking multiple @Conditional* annotations requires all conditions to pass.

Annotation	Activates when…
`@ConditionalOnClass`	All listed classes are on the classpath.
`@ConditionalOnMissingClass`	None of the listed classes are on the classpath.
`@ConditionalOnBean`	A bean of the given type or name already exists.
`@ConditionalOnMissingBean`	No bean of the given type or name exists (lets users override).
`@ConditionalOnProperty`	A configuration property has a specific value.
`@ConditionalOnResource`	A specific resource is present on the classpath.
`@ConditionalOnWebApplication`	The application is a web application.
`@ConditionalOnNotWebApplication`	The application is not a web application.
`@ConditionalOnSingleCandidate`	Exactly one candidate bean of the given type exists.
`@ConditionalOnExpression`	A SpEL expression evaluates to `true`.

@ConditionalOnMissingBean is the standard pattern auto-configurations use to back off when you provide your own bean. Define your own @Bean of the same type to take full control and disable the auto-configured one.

Disabling specific auto-configurations

You can exclude auto-configurations you do not want:

@SpringBootApplication
properties

@SpringBootApplication(exclude = { DataSourceAutoConfiguration.class })
public class MyApplication { }

spring.autoconfigure.exclude=\
  org.springframework.boot.jdbc.autoconfigure.DataSourceAutoConfiguration

Auto-configuration classes by category

The classes below are read from the META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports files in the Spring Boot source. Only selected, commonly used classes are listed here; run --debug to see the complete list for your application.

Core

These auto-configurations are always considered regardless of which starters are on the classpath.

Class	Purpose
`org.springframework.boot.autoconfigure.context.ConfigurationPropertiesAutoConfiguration`	Enables `@ConfigurationProperties` bean processing.
`org.springframework.boot.autoconfigure.context.MessageSourceAutoConfiguration`	Auto-configures `MessageSource` for internationalization.
`org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration`	Registers a `PropertySourcesPlaceholderConfigurer` for `${…}` resolution.
`org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration`	Configures an `AsyncTaskExecutor` for `@Async` and virtual threads.
`org.springframework.boot.autoconfigure.task.TaskSchedulingAutoConfiguration`	Configures a `ThreadPoolTaskScheduler` for `@Scheduled`.
`org.springframework.boot.autoconfigure.aop.AopAutoConfiguration`	Enables Spring AOP via `@EnableAspectJAutoProxy`.
`org.springframework.boot.autoconfigure.ssl.SslAutoConfiguration`	Registers SSL bundles from `spring.ssl.bundle.*` properties.

Web (Servlet and Reactive)

Web auto-configurations set up the dispatcher, error handling, HTTP encoding, and view technologies.

Class	Purpose
`org.springframework.boot.webmvc.autoconfigure.DispatcherServletAutoConfiguration`	Registers `DispatcherServlet` for Spring MVC.
`org.springframework.boot.webmvc.autoconfigure.WebMvcAutoConfiguration`	Configures Spring MVC defaults (content negotiation, formatters, static resources).
`org.springframework.boot.webmvc.autoconfigure.error.ErrorMvcAutoConfiguration`	Provides the default `/error` endpoint and `BasicErrorController`.
`org.springframework.boot.servlet.autoconfigure.HttpEncodingAutoConfiguration`	Sets the character encoding for HTTP requests and responses.
`org.springframework.boot.servlet.autoconfigure.MultipartAutoConfiguration`	Configures multipart file upload support.
`org.springframework.boot.webflux.autoconfigure.WebFluxAutoConfiguration`	Configures Spring WebFlux for reactive web applications.
`org.springframework.boot.webflux.autoconfigure.error.ErrorWebFluxAutoConfiguration`	Provides reactive error handling via `DefaultErrorWebExceptionHandler`.
`org.springframework.boot.thymeleaf.autoconfigure.ThymeleafAutoConfiguration`	Configures Thymeleaf template engine and view resolver.
`org.springframework.boot.freemarker.autoconfigure.FreeMarkerAutoConfiguration`	Configures FreeMarker template engine.
`org.springframework.boot.restclient.autoconfigure.RestClientAutoConfiguration`	Configures `RestClient.Builder` with default settings.
`org.springframework.boot.restclient.autoconfigure.RestTemplateAutoConfiguration`	Configures `RestTemplateBuilder` for `RestTemplate` creation.
`org.springframework.boot.webclient.autoconfigure.WebClientAutoConfiguration`	Configures `WebClient.Builder` for reactive HTTP clients.
`org.springframework.boot.graphql.autoconfigure.GraphQlAutoConfiguration`	Configures Spring for GraphQL schema and execution.
`org.springframework.boot.graphql.autoconfigure.servlet.GraphQlWebMvcAutoConfiguration`	Exposes GraphQL over HTTP in servlet applications.

Data (JDBC, JPA, NoSQL)

Data auto-configurations cover relational and NoSQL databases, connection pooling, and Spring Data repositories.

Class	Purpose
`org.springframework.boot.jdbc.autoconfigure.DataSourceAutoConfiguration`	Configures a `DataSource` (defaults to HikariCP).
`org.springframework.boot.jdbc.autoconfigure.JdbcTemplateAutoConfiguration`	Configures `JdbcTemplate` and `NamedParameterJdbcTemplate`.
`org.springframework.boot.jdbc.autoconfigure.JdbcClientAutoConfiguration`	Configures the fluent `JdbcClient` API.
`org.springframework.boot.jdbc.autoconfigure.DataSourceTransactionManagerAutoConfiguration`	Configures `DataSourceTransactionManager` for JDBC.
`org.springframework.boot.hibernate.autoconfigure.HibernateJpaAutoConfiguration`	Configures Hibernate as the JPA provider.
`org.springframework.boot.data.jpa.autoconfigure.DataJpaRepositoriesAutoConfiguration`	Enables `@EnableJpaRepositories` for Spring Data JPA.
`org.springframework.boot.data.jdbc.autoconfigure.DataJdbcRepositoriesAutoConfiguration`	Enables Spring Data JDBC repositories.
`org.springframework.boot.mongodb.autoconfigure.MongoAutoConfiguration`	Configures a MongoDB `MongoClient`.
`org.springframework.boot.data.mongodb.autoconfigure.DataMongoAutoConfiguration`	Configures MongoDB template and repositories.
`org.springframework.boot.data.redis.autoconfigure.DataRedisAutoConfiguration`	Configures `RedisTemplate` and `StringRedisTemplate`.
`org.springframework.boot.flyway.autoconfigure.FlywayAutoConfiguration`	Configures Flyway database migration.
`org.springframework.boot.liquibase.autoconfigure.LiquibaseAutoConfiguration`	Configures Liquibase database migration.
`org.springframework.boot.r2dbc.autoconfigure.R2dbcAutoConfiguration`	Configures a reactive R2DBC `ConnectionFactory`.
`org.springframework.boot.data.elasticsearch.autoconfigure.DataElasticsearchAutoConfiguration`	Configures Elasticsearch client and template.
`org.springframework.boot.data.neo4j.autoconfigure.DataNeo4jAutoConfiguration`	Configures Neo4j driver and template.
`org.springframework.boot.jooq.autoconfigure.JooqAutoConfiguration`	Configures jOOQ `DSLContext`.

Security

Security auto-configurations set up Spring Security’s filter chain, user details, OAuth2, and SAML2.

Class	Purpose
`org.springframework.boot.security.autoconfigure.SecurityAutoConfiguration`	Registers the default `SpringBootWebSecurityConfiguration` and `AuthenticationEventPublisher`.
`org.springframework.boot.security.autoconfigure.UserDetailsServiceAutoConfiguration`	Configures an in-memory `UserDetailsService` with a generated password (for development).
`org.springframework.boot.security.autoconfigure.web.servlet.ServletWebSecurityAutoConfiguration`	Enables `@EnableWebSecurity` in servlet applications.
`org.springframework.boot.security.autoconfigure.web.reactive.ReactiveWebSecurityAutoConfiguration`	Enables `@EnableWebFluxSecurity` in reactive applications.
`org.springframework.boot.security.oauth2.client.autoconfigure.OAuth2ClientAutoConfiguration`	Configures OAuth2 / OpenID Connect client support.
`org.springframework.boot.security.oauth2.server.resource.autoconfigure.OAuth2ResourceServerAutoConfiguration`	Configures JWT or opaque-token resource server validation.
`org.springframework.boot.security.oauth2.server.authorization.autoconfigure.servlet.OAuth2AuthorizationServerAutoConfiguration`	Configures Spring Authorization Server.
`org.springframework.boot.security.saml2.autoconfigure.Saml2RelyingPartyAutoConfiguration`	Configures SAML 2.0 relying party (service provider).

Messaging

Messaging auto-configurations support AMQP (RabbitMQ), Kafka, JMS, Pulsar, and other messaging systems.

Class	Purpose
`org.springframework.boot.amqp.autoconfigure.RabbitAutoConfiguration`	Configures RabbitMQ `ConnectionFactory`, `RabbitTemplate`, and listener containers.
`org.springframework.boot.kafka.autoconfigure.KafkaAutoConfiguration`	Configures Kafka `KafkaTemplate`, producer, consumer, and admin.
`org.springframework.boot.jms.autoconfigure.JmsAutoConfiguration`	Configures JMS `JmsTemplate` and listener container factory.
`org.springframework.boot.activemq.autoconfigure.ActiveMQAutoConfiguration`	Configures ActiveMQ Classic connection factory.
`org.springframework.boot.artemis.autoconfigure.ArtemisAutoConfiguration`	Configures ActiveMQ Artemis connection factory.
`org.springframework.boot.pulsar.autoconfigure.PulsarAutoConfiguration`	Configures Apache Pulsar client, producer, and consumer.
`org.springframework.boot.rsocket.autoconfigure.RSocketServerAutoConfiguration`	Configures an RSocket server.
`org.springframework.boot.integration.autoconfigure.IntegrationAutoConfiguration`	Configures Spring Integration message infrastructure.

Actuator and observability

Actuator auto-configurations expose production-ready endpoints. Observability auto-configurations integrate Micrometer metrics, tracing, and OpenTelemetry.

Class	Purpose
`org.springframework.boot.actuate.autoconfigure.endpoint.EndpointAutoConfiguration`	Core endpoint infrastructure (discovery, caching, security).
`org.springframework.boot.actuate.autoconfigure.endpoint.web.WebEndpointAutoConfiguration`	Exposes endpoints over HTTP.
`org.springframework.boot.health.autoconfigure.actuate.endpoint.HealthEndpointAutoConfiguration`	Configures the `/actuator/health` endpoint.
`org.springframework.boot.health.autoconfigure.application.DiskSpaceHealthContributorAutoConfiguration`	Adds a disk-space health indicator.
`org.springframework.boot.actuate.autoconfigure.env.EnvironmentEndpointAutoConfiguration`	Configures the `/actuator/env` endpoint.
`org.springframework.boot.actuate.autoconfigure.logging.LoggersEndpointAutoConfiguration`	Configures the `/actuator/loggers` endpoint for runtime log-level changes.
`org.springframework.boot.actuate.autoconfigure.beans.BeansEndpointAutoConfiguration`	Configures the `/actuator/beans` endpoint.
`org.springframework.boot.micrometer.metrics.autoconfigure.MetricsAutoConfiguration`	Configures the Micrometer `MeterRegistry`.
`org.springframework.boot.micrometer.metrics.autoconfigure.export.prometheus.PrometheusMetricsExportAutoConfiguration`	Exposes metrics in Prometheus format via `/actuator/prometheus`.
`org.springframework.boot.micrometer.observation.autoconfigure.ObservationAutoConfiguration`	Configures Micrometer `ObservationRegistry` for unified observability.
`org.springframework.boot.micrometer.tracing.autoconfigure.MicrometerTracingAutoConfiguration`	Integrates distributed tracing with Micrometer Tracing.
`org.springframework.boot.micrometer.tracing.brave.autoconfigure.BraveAutoConfiguration`	Configures Brave as the Micrometer Tracing implementation.
`org.springframework.boot.opentelemetry.autoconfigure.OpenTelemetrySdkAutoConfiguration`	Configures the OpenTelemetry SDK.

Caching and task execution

Class	Purpose
`org.springframework.boot.cache.autoconfigure.CacheAutoConfiguration`	Configures Spring’s `CacheManager` (auto-detects Caffeine, Redis, EhCache, etc.).
`org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration`	Configures the application `TaskExecutor` used for `@Async` and virtual threads.
`org.springframework.boot.autoconfigure.task.TaskSchedulingAutoConfiguration`	Configures `ThreadPoolTaskScheduler` for `@Scheduled` methods.
`org.springframework.boot.quartz.autoconfigure.QuartzAutoConfiguration`	Configures the Quartz `Scheduler` with JDBC or in-memory job stores.
`org.springframework.boot.batch.autoconfigure.BatchAutoConfiguration`	Configures Spring Batch infrastructure (job repository, launcher).

Writing your own auto-configuration

To package reusable auto-configuration as a library, create an @AutoConfiguration class and register it in your JAR’s META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports file:

@AutoConfiguration(after = DataSourceAutoConfiguration.class)
@ConditionalOnClass(MyService.class)
@EnableConfigurationProperties(MyProperties.class)
public class MyServiceAutoConfiguration {

    @Bean
    @ConditionalOnMissingBean
    MyService myService(MyProperties properties) {
        return new MyService(properties.getEndpoint());
    }
}

META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports

com.example.mylib.autoconfigure.MyServiceAutoConfiguration

Starters

Appendix

Auto-configuration Classes Reference for Spring Boot

How auto-configuration works

The `@AutoConfiguration` annotation

Ordering auto-configurations

Conditional annotations

Disabling specific auto-configurations

Auto-configuration classes by category

Writing your own auto-configuration

Build docs developers (and LLMs) love

Starters

Appendix

Documentation Index

​How auto-configuration works

​The @AutoConfiguration annotation

​Ordering auto-configurations

​Conditional annotations

​Disabling specific auto-configurations

​Auto-configuration classes by category

​Writing your own auto-configuration

Build docs developers (and LLMs) love

How auto-configuration works

The `@AutoConfiguration` annotation

Ordering auto-configurations

Conditional annotations

Disabling specific auto-configurations

Auto-configuration classes by category

Writing your own auto-configuration