🌿

Spring Annotations

The annotations a Spring developer reaches for every day.

Stereotypes & configuration

```
@Component
```
generic Spring-managed bean
```
@Service
```
business-logic bean (semantic)
```
@Repository
```
data access; translates persistence exceptions
```
@Configuration
```
class that declares @Bean methods
```
@Bean
```
method whose return value is a bean
```
@ConfigurationProperties("app")
```
bind typed config

Boot & context

```
@SpringBootApplication
```
config + auto-config + scan
```
@ComponentScan
```
where to look for beans
```
@Value("${app.name}")
```
inject a single property
```
@Profile("prod")
```
bean active only in a profile
```
@ConditionalOnMissingBean
```
back off if user defined one

Web (Spring MVC)

```
@RestController
```
@Controller + @ResponseBody
```
@RequestMapping("/api")
```
base path for a controller

@GetMapping @PostMapping @PutMapping @DeleteMapping

@PathVariable  @RequestParam  @RequestBody

bind request data

```
@Valid
```
trigger Bean Validation on the body
```
@RestControllerAdvice
```
global exception handling

Data & transactions

```
@Entity  @Id  @GeneratedValue
```
JPA mapping
```
@ManyToOne  @OneToMany  @ManyToMany
```
relationships
```
@Query("select b from Book b …")
```
custom JPQL/SQL
```
@Transactional
```
wrap a method in a DB transaction
```
@Transactional(readOnly = true)
```
read optimization

Security & testing

```
@EnableWebSecurity
```
turn on the security config
```
@PreAuthorize("hasRole('ADMIN')")
```
method-level rule
```
@SpringBootTest
```
full-context integration test
```
@WebMvcTest  @DataJpaTest
```
focused slice tests
```
@MockitoBean
```
replace a bean with a mock (Boot 3.4+)