backend-coding-standards

name	backend-coding-standards
description	HiMarket backend coding standards for Java and Spring Boot. Use whenever modifying or reviewing himarket-server, himarket-dal, himarket-bootstrap, backend Maven POMs, Flyway SQL, controllers, services, DTOs, repositories, validation, logging, exceptions, or backend tests. Read docs/standards/backend before editing.

HiMarket Backend Coding Standards

This skill is the entry point for HiMarket backend development standards. It should route the agent to the project documentation instead of duplicating the full rules here.

Source of Truth

The canonical backend standards live under:

• docs/standards/backend/README.md
• docs/standards/backend/project-structure.md
• docs/standards/backend/api-controller.md
• docs/standards/backend/service-transaction.md
• docs/standards/backend/dto-json.md
• docs/standards/backend/dependency-management.md
• docs/standards/backend/data-flyway.md
• docs/standards/backend/security-logging.md
• docs/standards/backend/testing.md

If this skill conflicts with docs/standards/backend, follow docs/standards/backend.

Activation

Use this skill for changes in:

• himarket-server
• himarket-dal
• himarket-bootstrap
• backend pom.xml files
• Flyway migration files
• backend tests and verification scripts

Reading Flow

Always read docs/standards/backend/README.md first. Then read the topic document that matches the change:

Change area	Read
Naming, annotation order, Lombok, dependency injection, imports, Stream, Optional, utilities	docs/standards/backend/project-structure.md
Controller routes, request validation, pagination, OpenAPI	docs/standards/backend/api-controller.md
Service orchestration, exceptions, transactions, events	docs/standards/backend/service-transaction.md
DTO conversion, JSON, polymorphic config	docs/standards/backend/dto-json.md
Maven dependencies and utility selection	docs/standards/backend/dependency-management.md
Entity mapping and Flyway migrations	docs/standards/backend/data-flyway.md
JavaDoc, comments, logging, sensitive data	docs/standards/backend/security-logging.md
Backend verification and test expectations	docs/standards/backend/testing.md

Working Rules

• Prefer existing code in the same layer or module as the local reference.
• For product-domain orchestration, use ProductServiceImpl as a useful reference, but keep smaller implementations simple when the scenario is smaller.
• Keep changes scoped to the user request and the touched module.
• Do not introduce unrelated refactors while applying a standard.
• Preserve user changes in the working tree.

High-Priority Reminders

• Use constructor injection through Lombok; do not use @Autowired.
• Follow the documented annotation order.
• Use block JavaDoc format for field and method comments that need JavaDoc.
• Use Stream only for simple, side-effect-free collection transformations.
• Use Optional only at absent-value boundaries, not as business control flow.
• Prefer JDK, Spring, and project helpers before adding broad utility dependencies.
• Keep logs in stable English with SLF4J placeholders and the throwable as the final argument.
• Keep troubleshooting values visible unless they are credentials, tokens, secrets, or credential payloads.
• Add @Validated when controller method parameters use Jakarta validation constraints.
• Validate collection elements when blank IDs inside a list are invalid.
• Use Spring transaction annotations from org.springframework.transaction.annotation.

Verification

For backend code changes, default to:

git diff --check
./mvnw -q spotless:check -DskipTests
./mvnw -q -DskipTests test-compile

Run targeted tests when behavior changes. For broader backend work, use one of:

• ./scripts/code-check.sh backend
• the command set in docs/standards/backend/testing.md