Codegen

Overview

Motivation

Building (RESTful) APIs in Java Spring Boot requires many of the same components: Controllers, Services, Mappers, Repository interfaces and/or data-access objects (DAOs), data-transfer-objects (DTO), and entity models. The business logic to implement CRUD operations for each domain is similar as well. Thus, many of these components can be abstracted with parameterized dependencies so that implementing them at the concrete level can be done with minimal lines of code. This abstraction is provided by the components submodule.

Although the components submodule greatly improves a developer’s ability to quickly implement Spring Boot components with full CRUD functionality, the developer experience requires implementing and/or extending the interfaces and abstract classes that have been parameterized. This task can be tedious and reduce developer productivity.

To improve the developer experience by reducing the amount of code necessary to implement CRUD functionality for a domain’s Spring Boot components, the codegen project uses code generation technologies to auto implement the Controller, Service, Mapper, Repository interfaces and/or DAOs and DTOs based on a domain's Entity model. It is the Entity model that typically dictates differences in the business logic, after all.

Community Context

Limitations

Architecture

Abstracted Components

Annotation

The codegen submodule generates Spring Boot components for RESTful APIs, with GraphQL support planned in the roadmap. At compile time, the project uses annotation processing with Java Poet to write Java files compile time based on the components submodule that

Annotation Processing

Usage

Examples

Pitfalls

Next Steps

Nested Annotations

DTO

• Implement DTO 1:1 based on Entity model
• Ability to exclude attributes in the DTO that are present in the Entity model.

Business Logic for nested entities

Criteria Specification Search

Testing

GraphQL Support