Spring Data JPA Showcase Development

Guide development of a full-stack Spring Data showcase application demonstrating Spring Data JPA features with a Spring Boot backend and Angular Material frontend.

Project Architecture

This is a full-stack Spring Data showcase with two main components:

**Backend (`backend/`):**

**Frontend (`frontend/`):**

Development Workflow

Backend Commands

When working with the Spring Boot backend:

```bash

Run the application (port 8080)

cd backend && mvn spring-boot:run

Run tests

mvn test

Build the project

mvn clean package

```

Frontend Commands

When working with the Angular frontend:

```bash

Start development server (port 4200)

cd frontend && ng serve

Install dependencies

npm install

Build for production

ng build

Run tests

ng test

Generate new component

ng generate component components/component-name

```

Spring Data Features Demonstrated

1. Query Methods

The ProductRepository demonstrates various Spring Data query method patterns:

2. REST API Design

The backend implements these endpoint patterns:

| Method | Endpoint | Purpose |

|--------|----------|---------|

| GET | `/api/products` | Get all products |

| GET | `/api/products/paged` | Paginated products with sorting |

| GET | `/api/products/{id}` | Get product by ID |

| POST | `/api/products` | Create new product |

| PUT | `/api/products/{id}` | Update product |

| DELETE | `/api/products/{id}` | Delete product |

| GET | `/api/products/category/{category}` | Filter by category |

| GET | `/api/products/search?name=` | Search by name |

| GET | `/api/products/search/keyword?keyword=` | Search by keyword |

| GET | `/api/products/price-range?minPrice=&maxPrice=` | Filter by price range |

3. Frontend Integration Patterns

The Angular frontend demonstrates:

Implementation Guidelines

When Adding Backend Features

1. **Repository Layer**: Add query methods following Spring Data naming conventions

2. **Service Layer**: Keep business logic separate from controllers

3. **Controller Layer**: Use proper HTTP methods and status codes

4. **Error Handling**: Implement proper validation and exception handling

5. **Testing**: Write unit tests for repositories and integration tests for endpoints

When Adding Frontend Features

1. **Components**: Keep components focused and reusable

2. **Services**: Centralize API calls in services

3. **Material UI**: Use Angular Material components consistently

4. **Forms**: Use reactive forms with proper validation

5. **State Management**: Keep component state minimal and focused

Code Organization

```

backend/

├── src/main/java/

│ └── com/example/showcase/

│ ├── model/ # JPA entities

│ ├── repository/ # Spring Data repositories

│ ├── service/ # Business logic

│ └── controller/ # REST endpoints

└── src/main/resources/

└── application.properties # Configuration

frontend/

├── src/app/

│ ├── components/ # Angular components

│ ├── services/ # HTTP services

│ └── models/ # TypeScript interfaces

└── angular.json # Angular configuration

```

Key Constraints

Testing Strategy

**Backend:**

**Frontend:**

Next Steps for Extension

When extending this showcase:

1. Add more complex query examples (Specifications, QueryDSL)

2. Implement additional Spring Data features (Projections, Auditing)

3. Add authentication/authorization examples

4. Demonstrate caching strategies

5. Show performance optimization techniques

6. Add GraphQL endpoint examples

7. Implement real-time updates with WebSockets