Spring Boot AspectJ Logging Example

This project demonstrates how to use AspectJ in a Spring Boot application to perform automatic logging for key operations like creating, retrieving, and deleting accounts.

📜 What is an Aspect?

An Aspect is a modularization of a concern that cuts across multiple classes, like logging, security, or transaction management. In Aspect-Oriented Programming (AOP), aspects help you separate these concerns cleanly from your business logic.

In this project, we use AspectJ (a popular AOP framework) to create a reusable logging aspect that automatically logs method execution without cluttering your business code.

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🚀 How it Works

• The @Loggable annotation is used to mark methods that should be automatically logged.
• The LoggingAspect class intercepts method calls annotated with @Loggable.
• It logs method entry, arguments, execution time, and method exit.

For example:

@Loggable
public Account execute(UUID id) {
    // Business logic
}

Any method annotated with @Loggable will be automatically logged.

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🛠️ Project Structure

File	Description
@Loggable	Custom annotation to mark methods for logging.
LoggingAspect	Aspect that captures and logs method calls at runtime.
CreateAccountUseCaseImpl	Example service for creating an account.
GetAccountUseCaseImpl	Example service for retrieving an account.
DeletetAccountUseCaseImpl	Example service for deleting an account.
AccountDTO, AccountRequest	DTOs used in API communication.

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🔥 Running the Application

1. Clone the repository.
2. Run the application with your favorite IDE or mvn spring-boot:run.
3. Use the following curl commands to test the endpoints:

➕ Create an Account

curl --location 'http://localhost:8080/accounts' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--data '{
    "username": "johndoe",
    "password": "securePassword123",
    "id": "a8bdb935-6bac-4621-94f3-bacbf69e4409"
}'

🔍 Get an Account

curl --location 'localhost:8080/accounts/bb2cc380-2f3d-4b0b-aa65-b216753b83a5'

❌ Delete an Account

curl --location --request DELETE 'http://localhost:8080/accounts/123e4567-e89b-12d3-a456-426614174000' --header 'Accept: application/json'

All these operations will automatically trigger logs thanks to the AspectJ configuration!

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📋 Example Log Output

When you call one of the endpoints, you might see logs like:

[LOG] Entering method: GetAccountUseCaseImpl.execute(UUID)
Arguments: [bb2cc380-2f3d-4b0b-aa65-b216753b83a5]
[LOG] Exiting method: GetAccountUseCaseImpl.execute(UUID) after 12ms
Returned: Account(id=bb2cc380-2f3d-4b0b-aa65-b216753b83a5, username=Test, ...)

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📚 References

• Spring AOP Documentation
• AspectJ Documentation