AnnotationMappingDiscoverer should read @RequestMapping#params()

[sp00m]

@RequestMapping allows to use requests' GET parameters to map incoming requests without having to inject parameters into a @RequestParam annotated method parameter:

@RequestMapping(method = GET, value = "/foobar", params = { "!one", "two", "three!=3", "four=4" })
public ResponseEntity<?> get() {
  return foobar();
}

This is pretty useful when you want clean API endpoints as well as clean code (e.g. no need of single method delegating to other methods thanks to a switch/case on the parameter's value).

It could be great if linkTo(methodOn(FooBarApi.class).get()) took these params into account as well, by generating for the above example at least:

http://example.com/foobar?four=4

And why not:

http://example.com/foobar?four=4&two=true

But iff no @RequestParam matched this two parameter (otherwise, the actual value would have been given when calling linkTo(methodOn(FooBarApi.class).get(twoParamValue))).

What do you think about it?

Technically, when dealing with the @RequestMapping annotation, the AnnotationMappingDiscoverer instance used in ControllerLinkBuilderFactory could instantiate an new org.springframework.web.servlet.mvc.condition.ParamsRequestCondition to parse thoses params.

[odrotbohm]

This should be in place thanks to @reda-alaoui's contribution. Minor comment on the original description: we do not add two=true as suggested as there's no value given in the params definition.