Java-to-OpenAPI

Java-to-OpenAPI is a command-line interface (CLI) tool that converts Java classes into OpenAPI 3 specifications in YAML format. This tool is useful for developers who want to automatically generate OpenAPI documentation from Java classes.

Installation

You can use java-to-openapi directly with npx, without the need for prior installation:

npx java-to-openapi <source-directory> <output-file>

Usage

Basic Command

To use the tool, run the command:

npx java-to-openapi <source-directory> <output-file>

• <source-directory>: The path to the directory containing the .java files.
• <output-file>: The path and name of the output YAML file.

Example

If you have a src/example folder with your Java classes and want to generate an api-spec.yaml file in the project root, run:

npx java-to-openapi ./src/example ./api-spec.yaml

File Structure

src/
└── example/
    ├── Produto.java
    └── Categoria.java

Features

• Java Class Conversion: Analyzes Java classes and automatically generates the corresponding OpenAPI 3 specification.
• Primitive Type Support: Converts common Java types (int, String, boolean, etc.) to their OpenAPI equivalents.
• List Support: Identifies and converts lists (List) to arrays in OpenAPI.
• Recursiveness: Processes .java files in subdirectories recursively.

Supported Class Examples

The tool supports both simple and complex classes, including those containing lists or references to other classes.

Example Java Class:

import java.util.List;

public class Produto {
    private int id;
    private String nome;
    private double preco;
    private boolean emEstoque;
    private Categoria categoria;
    private List<String> tags;
    private List<Categoria> categoriasRelacionadas;

    // Getters and Setters omitted for brevity
}

YAML Output:

openapi: 3.0.0
info:
  title: API Documentation
  version: 1.0.0
components:
  schemas:
    Produto:
      type: object
      properties:
        id:
          type: integer
        nome:
          type: string
        preco:
          type: number
        emEstoque:
          type: boolean
        categoria:
          $ref: '#/components/schemas/Categoria'
        tags:
          type: array
          items:
            type: string
        categoriasRelacionadas:
          type: array
          items:
            $ref: '#/components/schemas/Categoria'
    Categoria:
      type: object
      properties:
        id:
          type: integer
        nome:
          type: string

Contributing

If you find any bugs or have suggestions for improvements, feel free to open an issue or submit a pull request.

License

This project is licensed under the MIT License. See the LICENSE file for more details.

Author

Developed by Gabriell Huver.