@Transactional Usage & Rollbacks

How @Transactional Works in Spring

Spring uses AOP proxies to intercept methods annotated with `@Transactional`. It opens a database connection, begins a transaction, and commits upon completion.

Rollback Rules:

• Default Rollback: Spring rolls back ONLY for unchecked exceptions (`RuntimeException` and `Error`).
• Checked Exception Rollback: Must explicitly set `@Transactional(rollbackFor = Exception.class)`.
• readOnly Optimization: Use `@Transactional(readOnly = true)` for SELECT queries to allow DB performance optimizations.

Production Code Example:

package com.anujsingh.digitalguru.service;

import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
public class PaymentService {

    @Transactional(rollbackFor = Exception.class)
    public void processPayment() throws Exception {
        // Payment logic
    }
}

Key Architectural Concepts & Best Practices:

When working with @Transactional Usage & Rollbacks in enterprise Spring Boot applications, keep these key architectural guidelines in mind:

• Separation of Concerns: Maintain a strict boundary between HTTP endpoints, service logic, and database persistence layers.
• Framework Conventions: Rely on Spring Boot auto-configuration defaults whenever possible, overriding settings only via application.yml or @Configuration classes when customized behavior is required.
• Production Monitoring & Reliability: Ensure proper exception handling, thread-safety, and resource cleanup to prevent memory leaks and unexpected runtime downtime.
• Developer Ergonomics: Write clean, self-documenting code with modern Java features (Records, Lambdas, Streams) to simplify code reviews and maintenance.

Summary Takeaway:

Mastering @Transactional Usage & Rollbacks ensures that your Java & Spring Boot backend microservices remain maintainable, secure, and compliant with modern enterprise software engineering standards.