Light-Java provide a plugin architecture and dozens of middleware handlers to address cross-cutting concerns in general. When you decide to build an API or service, you have to choose from different styles and corresponding framework to get started.
For API categories and frameworks, please find details here
Chances are you are building a public Web API and want to follow RESTful style to make sure everyone can understand and consume it.
Light-rest-4j is a framework that is designed to speed up RESTful API development and deployment. On top of light-4j, it has several middleware handlers specifically designed around OpenAPI specification.