An abstraction for hypermedia libraries (like HTMX, Unpoly and Hotwired Turbo) with Spring MVC. Features:

• A @RequestMapping can be annotated with @HyperTextMapping to select it for rendering special content. Typically this will be part of a page, not a whole HTML page.
• HyperTextResponse as a return value from a @RequestMapping method. This is a collection of view renderings, typically HTML fragments. It can also be used to set additional headers on the response.
• HyperTextRequest as a method argument for a @RequestMapping method. It detects a hypermedia request from one of the libraries and allows the controller to react to it.
• MultiViewResolver is a ViewResolver that splits its view name parameter by commas and resolves each part separately. This allows a controller to return multiple views in a single response without using HyperTextResponse (but all the views get the same model when they render).

HTMX, Unpoly and Turbo each get their own specific version of the @HyperTextMapping annotation and the HyperTextResponse. This allows the controller to react differently to requests from different libraries.

Example with HTMX:

@HtmxMapping
@PostMapping(path = "/greet")
HtmxResponse name(Map<String, Object> model, @RequestParam String name) {
	...
	return HtmxResponse.builder().view("greet::main").view("layout::menu").build();
}

or taking advantage of the MultiViewResolver and HyperTextRequest:

@PostMapping(path = "/greet")
String name(Map<String, Object> model, @RequestParam String name, HyperTextRequest hx) {
	...
	return hx.isActive() ? "greet::main,layout::menu" : "greet";
}