DDD4j Project Creator
When to use this skill
CRITICAL: This skill should ONLY be triggered when the user explicitly mentions creating a ddd4j project, initializing ddd4j project, or setting up ddd4j-boot project.
ALWAYS use this skill when the user mentions:
- Creating a ddd4j project (explicitly mentions "ddd4j")
- Initializing ddd4j-boot project
- Setting up ddd4j project structure
- Creating ddd4j project scaffolding
- 创建 ddd4j 项目 (explicitly mentions "ddd4j")
- 初始化 ddd4j 项目 (initialize ddd4j project)
- ddd4j-boot 项目创建 (create ddd4j-boot project)
Trigger phrases include:
- "创建 ddd4j 项目" (create ddd4j project) - must include "ddd4j"
- "初始化 ddd4j 项目" (initialize ddd4j project) - must include "ddd4j"
- "创建 ddd4j-boot 项目" (create ddd4j-boot project) - must include "ddd4j"
- "使用 ddd4j 创建项目" (create project using ddd4j)
- "ddd4j 项目脚手架" (ddd4j project scaffolding)
DO NOT trigger this skill for:
- Generic DDD projects without mentioning ddd4j
- JPA/Hibernate projects
- Other ORM frameworks
- Generic project initialization without ddd4j context
- "创建 DDD 项目" without "ddd4j" (too generic)
- "初始化项目" without "ddd4j" (too generic)
About DDD4j Boot
DDD4j Boot is a Java microservice development scaffold based on Domain-Driven Design (DDD) principles. It is built with Spring Boot 3.5.x and uses lightweight ddd-4-java and cqrs-4-java libraries to implement Domain-Driven Design, Command Query Responsibility Segregation (CQRS), and Event Sourcing.
Core Design Principles
- Domain-Driven Design (DDD): Strategic design through bounded contexts, tactical design with entities, value objects, aggregates, domain services, repositories, and domain events
- Command Query Responsibility Segregation (CQRS): Separation of read and write models, independent optimization
- Event Sourcing: State changes recorded as event sequences, supporting complete history and state reconstruction
- Diamond Architecture (COLA): Adapter → Application → Domain ← Infrastructure four-layer architecture
Key Features
- Complete DDD layered architecture supporting COLA V5 pattern
- Lightweight DDD implementation based on ddd-4-java and cqrs-4-java
- Technology stack integration: Spring Boot 3.5.x, MyBatis Plus, Jackson, Guava, Swagger, SaToken
- Dual stack support: WebMVC (traditional Servlet) and WebFlux (reactive)
- Domain model base capabilities: BaseEntity, BaseRepository, BaseService
- Domain event support with built-in event publishing mechanism
- Anti-Corruption Layer (ACL) for external service integration
- Unified exception handling mechanism
Project Types Supported
1. Single-Module Monolith (单体单模块)
适用场景: 中小型应用,单个业务领域,团队规模 5-15 人
特点:
- 单一 Maven 模块
- 所有层(interfaces, application, domain, infrastructure)在同一模块内
- 适合快速开发和部署
2. Multi-Module Monolith (单体多模块)
适用场景: 中大型应用,多个业务域,团队规模 15-50 人
特点:
- 多个 Maven 模块,按业务域划分
- 每个业务域包含完整的 DDD 四层架构
- 共享 common 模块
- 统一 BOM 和依赖管理
3. Microservices (单体微服务)
适用场景: 大型电商平台,多个业务域,团队规模 50+ 人
特点:
- 每个服务独立部署
- 服务间通过 RPC 和消息队列通信
- 每个服务内部按 DDD 四层架构组织
- 独立的数据库和配置
How to use this skill
CRITICAL: This skill should ONLY be triggered when the user explicitly mentions creating a ddd4j project. Do NOT trigger for generic DDD project creation requests without ddd4j context.
For New DDD4j Project Creation
- Identify the project type from user requirements:
- Single-module monolith → single-module - Multi-module monolith → multi-module - Microservices → microservices
- Load the appropriate example from the
examples/directory:
- examples/single-module.md - Single-module monolith structure - examples/multi-module.md - Multi-module monolith structure - examples/microservices.md - Microservices structure - examples/architecture-patterns.md - DDD, Hexagonal, Clean, COLA V5 patterns
- Collect project information:
- groupId: Maven group ID (e.g., com.github.hiwepy or io.ddd4j.base) - artifactId: Maven artifact ID (e.g., ddd4j-douyin or my-ddd4j-service) - version: Project version (e.g., 1.0.0-SNAPSHOT) - parentVersion: Parent POM version (e.g., 2023.0.x.20251205-SNAPSHOT or reference to ddd4j-boot-parent) - packageBase: Base package name (e.g., io.ddd4j.douyin or com.example.service) - modules: List of business modules (for multi-module/microservices) - architecture: Architecture pattern (DDD Classic, Hexagonal, Clean, COLA V5) - ddd4jBootVersion: DDD4j Boot version (if using ddd4j-boot-bom)
- Generate project structure:
- Create directory structure based on selected type - Generate pom.xml files (parent and modules) - Create package-info.java files for each module - Generate .gitignore, LICENSE, mvnw, mvnw.cmd - Create basic directory structure with src/main/java and src/test/java
- Save to project directory:
- Default location: Save directly to the command execution directory (same level as the command) - Directory creation: Automatically create the project directory structure if it doesn't exist - File naming: Use descriptive names based on project type and module names
For Existing Project Validation
- Analyze project structure:
- Scan project directory for Maven modules - Identify layer structure (interfaces, application, domain, infrastructure) - Check package naming conventions - Verify directory organization
- Identify project type:
- Single-module: Single pom.xml at root, all layers in one module - Multi-module: Parent pom.xml with multiple modules, each module has complete layers - Microservices: Multiple services, each with independent structure
- Validate against standards:
- Check DDD layer compliance - Verify dependency direction (interfaces → application → domain ← infrastructure) - Validate package naming ({basePackage}.{module}.{layer}) - Check for required directories (src/main/java, src/test/java) - Verify package-info.java files exist
- Generate validation report:
- List identified issues - Provide recommendations - Suggest fixes for non-compliant structures
Output Format and File Saving
When generating a project structure, follow this response structure:
- Save the files first: Create the project structure directly in the command execution directory
- The project will be created at the same level as where the command is executed - Generate all required files and directories (pom.xml, src/, etc.) - Use the artifactId as the project root directory name
- Inform the user: Tell them where the files were saved
- Display the structure: Show the generated directory structure in a code block
Example Response Structure:
- First line: "I've created the DDD project structure and saved it to
./{artifactId}/in the current directory." - Then show the structure wrapped in a code block:
- Start with: three backticks + text + newline - Then the directory structure - End with: three backticks + newline
Critical Requirements:
- Always save project files directly to the command execution directory (same level)
- Use artifactId as the project root directory name
- Create the directory structure automatically if it doesn't exist
- Generate complete project structure with all required files
- Follow Maven and DDD conventions strictly
Project Structure Standards
Package Naming Convention
For multi-module projects:
{basePackage}.{moduleName}.{layerName}Examples:
io.ddd4j.douyin.api.domain- API module, domain layerio.ddd4j.douyin.api.application- API module, application layerio.ddd4j.douyin.api.interfaces- API module, interfaces layerio.ddd4j.douyin.api.infrastructure- API module, infrastructure layer
Required Files
Every module must have:
pom.xml- Maven configurationsrc/main/java/{package}/package-info.java- Package documentationsrc/test/java/- Test directory structure.gitignore- Git ignore rules (at root)LICENSE- License file (at root)mvnw,mvnw.cmd- Maven wrapper (at root)
Layer Dependencies
Correct dependency direction:
interfaces → application → domain ← infrastructureRules:
- Domain layer must not depend on any other layer
- Infrastructure layer implements domain layer interfaces
- Application layer depends on domain layer
- Interfaces layer depends on application layer
Architecture Patterns
The skill supports four architecture patterns:
- DDD Classic Layered Architecture (DDD 经典分层架构)
- Layers: interfaces, application, domain, infrastructure - Reference: docs/1、DDD 经典分层架构目录结构.md and examples/architecture-patterns.md#ddd-classic
- Hexagonal Architecture (六边形架构)
- Ports and Adapters pattern - Reference: docs/2、六边形架构详细目录结构参考.md and examples/architecture-patterns.md#hexagonal
- Clean Architecture (整洁架构)
- Entities, Use Cases, Interface Adapters - Reference: docs/3、整洁架构详细目录结构参考.md and examples/architecture-patterns.md#clean
- COLA V5 (菱形架构)
- Adapter → App → Domain ← Infrastructure - Reference: docs/4、COLA V5 架构详细目录结构参考.md and examples/architecture-patterns.md#cola-v5
Validation Rules
When checking existing projects, validate:
- Structure Compliance:
- ✓ Correct layer organization - ✓ Proper module separation - ✓ Package naming conventions
- Dependency Rules:
- ✓ Domain layer has no external dependencies - ✓ Infrastructure implements domain interfaces - ✓ Correct dependency direction
- File Organization:
- ✓ Required directories exist - ✓ package-info.java files present - ✓ Maven configuration correct
- Naming Conventions:
- ✓ Package names follow convention - ✓ Module names are descriptive - ✓ Layer names are standard
Examples
See the examples/ directory for:
single-module.md- Complete single-module monolith examplemulti-module.md- Complete multi-module monolith example (based on ddd4j-douyin structure)microservices.md- Complete microservices examplearchitecture-patterns.md- All four architecture patterns with detailed structures
Keywords
English keywords: ddd4j, ddd4j-boot, ddd4j project, create ddd4j project, initialize ddd4j project, ddd4j project creator, ddd4j project scaffolding, ddd4j-boot project, ddd4j project structure, ddd4j-boot initialization, ddd4j microservice, ddd4j monolith
Chinese keywords (中文关键词): ddd4j, ddd4j-boot, ddd4j 项目, 创建 ddd4j 项目, 初始化 ddd4j 项目, ddd4j 项目创建, ddd4j 项目脚手架, ddd4j-boot 项目, ddd4j 项目结构, ddd4j-boot 初始化, ddd4j 微服务, ddd4j 单体应用
IMPORTANT: All keywords must include "ddd4j" to avoid false triggers. Generic terms like "DDD 项目" (DDD project) or "创建项目" (create project) without "ddd4j" should NOT trigger this skill.