Profiles & Environments

What Are Profiles, and Why Do They Exist?

A Spring profile is a named configuration scope. When a profile is active, Spring loads its profile-specific property files and registers only the beans annotated for that profile — everything else stays exactly the same. The result is one application binary that behaves differently in development, CI, and production without any code changes between environments.

This fits directly into the property source priority system covered in Application Properties: profile-specific files (application-prod.properties) sit higher in the priority order than the default application.properties, so they selectively override only the keys that genuinely differ per environment while the shared base file covers the rest.

Profile-Specific Property Files

src/main/resources/
├── application.properties          # Shared defaults — loaded always
├── application-dev.properties      # Loaded only when "dev" profile is active
├── application-test.properties     # Loaded only when "test" profile is active
└── application-prod.properties     # Loaded only when "prod" profile is active

# application.properties — keys shared by ALL environments
app.name=My Application
spring.jpa.open-in-view=false

# application-dev.properties — dev overrides only
spring.datasource.url=jdbc:h2:mem:devdb
spring.jpa.hibernate.ddl-auto=create-drop  # destroys schema on shutdown — fine for dev, never for prod
spring.jpa.show-sql=true
logging.level.com.example=DEBUG

# application-prod.properties — prod overrides only
spring.datasource.url=${DB_URL}            # resolved from env var — never hardcoded here
spring.jpa.hibernate.ddl-auto=validate
logging.level.root=WARN

Activating Profiles

# In application.properties — useful for local dev, never commit "prod" here
spring.profiles.active=dev

# Command-line argument — overrides the file, useful for one-off runs
java -jar app.jar --spring.profiles.active=prod

# Environment variable — the correct approach in containers and CI/CD
export SPRING_PROFILES_ACTIVE=prod
java -jar app.jar

# Multiple profiles — all their property files are loaded, all their @Profile beans register
java -jar app.jar --spring.profiles.active=prod,metrics,featureX

Profile-Conditional Beans

// Two implementations of the same interface — only one registers per profile
@Service
@Profile("dev")
public class MockEmailService implements EmailService {
    @Override
    public void send(String to, String body) {
        log.info("[DEV] Fake email to {}: {}", to, body);  // no real email sent
    }
}

@Service
@Profile("prod")
public class SmtpEmailService implements EmailService {
    @Override
    public void send(String to, String body) { /* real SMTP */ }
}

@Configuration
public class DataSourceConfig {

    // Registers in any profile except prod — dev, test, staging, local, etc.
    @Bean
    @Profile("!prod")
    public DataSource embeddedDataSource() {
        return new EmbeddedDatabaseBuilder()
            .setType(EmbeddedDatabaseType.H2)
            .build();
    }

    // Prod DataSource reads its config from @ConfigurationProperties — no hardcoded URLs here
    @Bean
    @Profile("prod")
    public DataSource prodDataSource(DataSourceProperties props) {
        return props.initializeDataSourceBuilder().build();
        // spring.datasource.url/username/password are resolved from env vars in prod
    }

    // Seed data loader — only outside prod, AND only when the "seed" feature profile is active
    @Bean
    @Profile({"dev", "test"})
    public DataInitializer dataInitializer() {
        return new DataInitializer();
    }
}

YAML Multi-Document — All Profiles in One File

# application.yml — shared defaults (no profile block)
app:
  name: My Application
spring:
  jpa:
    open-in-view: false

---
# Document 2 — active only when profile "dev" is active
spring:
  config:
    activate:
      on-profile: dev
  datasource:
    url: jdbc:h2:mem:devdb
  jpa:
    hibernate:
      ddl-auto: create-drop
    show-sql: true

---
# Document 3 — active only when profile "prod" is active
spring:
  config:
    activate:
      on-profile: prod
  datasource:
    url: "${DB_URL}"
  jpa:
    hibernate:
      ddl-auto: validate
logging:
  level:
    root: WARN

Profiles in Tests

// @ActiveProfiles activates the named profile for the entire test class
@SpringBootTest
@ActiveProfiles("test")
class UserServiceIntegrationTest {
    // Loads application.properties + application-test.properties
    // Registers all @Profile("test") beans, none of the @Profile("prod") ones
}

// @DataJpaTest already activates an embedded database — combine with a custom profile
// to load test-specific seed data or configuration without a full context
@DataJpaTest
@ActiveProfiles("test")
class UserRepositoryTest { ... }

# application-test.properties — test-specific overrides
spring.datasource.url=jdbc:h2:mem:testdb;DB_CLOSE_DELAY=-1
spring.jpa.hibernate.ddl-auto=create-drop
logging.level.root=WARN  # suppress noise during test runs

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