Showing Posts From
Framework
Jason Yang · 02 Jun, 2026
Optimistic locking in Spring Boot and JPA: how it works and how to make it production-ready with retries, backoff, jitter, observability, and fallback.
System Design
Jason Yang · 26 Mar, 2026
A practical Kafka testing strategy using Spring EmbeddedKafka and Python testcontainers. Learn how to test producers and consumers with real Kafka instead of mocks.
System Design
Jason Yang · 26 Mar, 2026
Implement a Kafka producer and consumer in Spring Boot: KafkaTemplate, @KafkaListener, manual ACK, retry handling, and Dead Letter Topic best practices.
Framework
Jason Yang · 26 Jan, 2026
MapStruct is a compile-time mapping tool for Spring projects that reduces boilerplate, improves safety, and makes DTO mapping cleaner and more testable.
Programming Language
Jason Yang · 08 Jan, 2026
FastAPI vs Spring Core: how Python and Java differ on DI, singleton scope, resource lifecycle, and execution models — a practical developer comparison.
Programming Language
Jason Yang · 01 Jan, 2026
Lombok's @Builder ignores your field defaults — use @Builder.Default or final to keep them. Here's why it happens and how to fix it.
Programming Language
Jason Yang · 02 Dec, 2025
Add a gRPC endpoint to a Spring Boot order-service: define .proto files, generate stubs, implement the RPC logic, and expose a new CreateOrder API.
Programming Language
Jason Yang · 29 Nov, 2025
Exception logging in Java done right: catch errors in the correct layer, log them once, and keep clear context — practical patterns for real systems.
Programming Language
Jason Yang · 29 Nov, 2025
Design effective custom exceptions in Java: structure them well, separate business and system errors, and integrate cleanly with Spring Boot error handling.
Programming Language
Jason Yang · 28 Nov, 2025
Why real Spring Boot developers prefer unchecked exceptions over the textbook rules — modern exception-handling patterns for clean, maintainable service code.
Framework
Jason Yang · 22 Nov, 2025
Spring Boot 'required a bean of type String' error? It often hits when switching to constructor injection. How to correctly inject @Value into constructors.
Framework
Jason Yang · 22 Nov, 2025
Integrate Swagger (OpenAPI) into Spring Boot with springdoc: secure your endpoints with JWT auth and auto-generate the API docs.
