Spring Boot Course
Spring Boot Configuration Annotations
@SpringBootApplication
Combines @Configuration, @EnableAutoConfiguration, and @ComponentScan.
Marks the main application class
@EnableAutoConfiguration
Enables Spring Boot’s auto-configuration mechanism.
@PropertySource
Loads properties files into the Spring Environment.
@ConfigurationProperties
Binds properties from application.properties/application.yml to a Java object.
Core Spring Annotations
@Configuration
Marks a class as a source of bean definitions.
@ComponentScan
Configures component scanning for Spring Beans.
@Bean
Indicates that a method produces a bean to be managed by the Spring container.
@RestController
Combination of @Controller and @ResponseBody. Used for REST APIs.
@Controller
Marks a class as a Spring MVC Controller.
@RequestMapping
Maps HTTP requests to handler methods.
Variants: @GetMapping, @PostMapping, @PutMapping, @DeleteMapping, @PatchMapping.
@ResponseBody
Indicates that the return value of a method should be written directly to the HTTP response.
@RequestBody
Binds the HTTP request body to a method parameter.
@RequestParam
Binds a request parameter to a method parameter.
@PathVariable
Binds a URI template variable to a method parameter.
@ExceptionHandler
Handles exceptions for a specific controller.
Dependency Injection and Stereotypes
@Component
Indicates a Spring-managed component.
@Service
Specialization of @Component for service classes.
@Repository
Specialization of @Component for persistence classes.
@Autowired
Automatically injects dependencies.
@Qualifier
Specifies which bean to inject when multiple candidates exist.
@Primary
Indicates the default bean to use when multiple candidates exist.
Spring Data JPA Annotations
@Entity
Marks a class as a JPA entity.
@Table
Specifies the table associated with a JPA entity.
@Id
Marks a field as the primary key.
@GeneratedValue
Specifies the primary key generation strategy.
@Column
Maps a field to a column in the database.
@ManyToOne, @OneToMany, @OneToOne, @ManyToMany
Define relationships between entities.
@Repository
Indicates a repository that interacts with the database.
@Query
Defines a custom SQL or JPQL query.
@Transactional
Manages transaction boundaries.
Validation Annotations (Hibernate Validator)
@Valid
Triggers validation for an object.
@NotNull
Ensures a field is not null.
@NotEmpty
Ensures a field is not empty (for collections or strings).
@NotBlank
Ensures a string is not blank.
@Size
Validates the size of a collection, map, array, or string.
@Min, @Max
Validates minimum and maximum values.
@Pattern
Validates a string using a regex.
Spring Security Annotations
@EnableWebSecurity
Enables Spring Security in the application.
@Secured
Specifies roles allowed to execute a method.
@PreAuthorize
Specifies a SpEL expression to control access before a method is invoked.
@PostAuthorize
Specifies a SpEL expression to control access after a method is invoked.
Spring Test Annotations
@SpringBootTest
Loads the complete application context for testing.
@WebMvcTest
Loads only the web layer for testing.
@MockBean
Creates a mock and adds it to the Spring ApplicationContext.
@TestConfiguration
Custom configuration for test classes.
Scheduling and Asynchronous Annotations
@EnableScheduling
Enables scheduled tasks in the application.
@Scheduled
Schedules a method to run at fixed intervals or cron expressions.
@Async
Executes a method asynchronously.
Caching Annotations
@EnableCaching
Enables caching in the application.
@Cacheable
Indicates a method whose result should be cached.
@CacheEvict
Indicates a method to evict cache entries.
@CachePut
Updates the cache without skipping the method execution.
Miscellaneous
@Profile
Activates a bean only for specific profiles.
@Conditional
Registers a bean conditionally based on the context.
@Value
Injects values from properties files or environment variables.
@CrossOrigin
It enables cross-origin resource sharing only for this specific method.
@Scope
To change this default behavior, use @Scope spring annotation.
@SessionAttributes
Lists the names of model attributes which should be transparently stored in the session
@PreDestroy and @PostConstruct
Alternative way for bean initMethod and destroyMethod.
@Consumes
Used to specify the MIME media types of representations a resource can consume.
@Produces
Used to specify the MIME media types of representations a resource can produce
@Validated
To tell Spring to validate parameters that are passed into a method of the annotated class.