ddd4j Annotation

Overview

Choose annotations by their consumers and runtime semantics. Do not assume that an annotation's name implies it registers a Bean, persists a field, or fires an event.

When to Use

• Choosing which annotation family (ddd/Contract, cqrs, api, orm) fits a new field, method, or class.
• Applying @BizKey, @TenantId, @SystemId, @OnCreate, @OnUpdate, or @OrderBy to a PO and needing the consumer wired.
• Adding @ApiIdempotent, ApiModule, ApiOperationLog, or RawResponse to an endpoint and asking what must implement the behavior.
• Marking aggregate state changes with CreateEvent, UpdateEvent, or DeleteEvent.
• Reviewing existing annotation usage: retention, target, defaults, and whether a real consumer exists.
• Introducing a new ddd4j annotation and its test set (independence, default-value, target, consumer).

When NOT to Use

Do not use this skill when: