Modern applications run in multiple environments—development, testing, staging, and production.
Spring Boot provides Profiles to manage environment-specific configuration cleanly without changing code.

This post explains how profiles work, how to configure them, and how to use them effectively.

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1. What Is a Spring Profile?

A Spring Profile represents a named logical environment.

Common profiles:

• dev
• test
• qa
• prod

Profiles allow Spring Boot to:

• Load different configuration
• Enable/disable beans
• Change behavior per environment

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2. Why Profiles Are Important

Without profiles, developers often:

• Hardcode values
• Use if-else logic
• Maintain multiple branches

Profiles solve this by:

• Keeping code clean
• Centralizing configuration
• Supporting CI/CD pipelines
• Improving security

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3. Profile-Specific Configuration Files

Spring Boot automatically detects profile-specific files.

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3.1 application.properties Example

application-dev.properties
application-prod.properties

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3.2 application.yml Example

spring:
  profiles:
    active: dev

And profile-specific files:

application-dev.yml
application-prod.yml

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4. Activating Profiles

Profiles can be activated in multiple ways.

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4.1 Using application.properties

spring.profiles.active=dev

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4.2 Using Command Line

java -jar app.jar --spring.profiles.active=prod

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4.3 Using Environment Variables

SPRING_PROFILES_ACTIVE=prod

This is commonly used in Docker and cloud deployments.

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5. Using @Profile on Beans

You can conditionally load beans using @Profile.

@Service
@Profile("dev")
public class DevEmailService { }

@Service
@Profile("prod")
public class ProdEmailService { }

Only one bean is loaded based on the active profile.

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6. Using @Profile with @Configuration

@Configuration
@Profile("test")
public class TestConfig { }

Useful for:

• Mock beans
• Test-specific setup
• Local development tools

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7. Multiple Active Profiles

Spring Boot supports multiple profiles at once.

spring.profiles.active=dev,feature-x

Profiles are applied in order, later ones overriding earlier ones.

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8. Default Profile

If no profile is active, Spring Boot uses:

default

You can define default configuration in:

• application.properties
• application.yml

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9. Common Mistakes

• Hardcoding profiles in code
• Committing prod secrets
• Forgetting to activate correct profile
• Mixing environment logic inside services

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10. Best Practices

• Use profiles only for environment differences
• Keep profile names simple
• Externalize secrets using environment variables
• Use @Profile for infrastructure beans
• Avoid business logic differences across profiles

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11. Real-World Example

Development:

• In-memory DB
• Debug logging

Production:

• External DB
• Optimized logging
• Security enabled

Profiles make this switch effortless.

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12. Summary

• Profiles enable environment-based configuration
• Profile-specific files are auto-detected
• Profiles can activate beans conditionally
• Multiple activation methods exist
• Profiles are essential for production-ready apps

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What's Next?

Next post:

34 - Spring Boot Logging – Complete Guide

We’ll explore logging configuration, levels, and best practices.