I was interested in this as well and came across some examples on the Spring Boot site.
// get with query string parameters e.g. /system/resource?id="rtze1cd2"&person="sam smith"
// so below the first query parameter id is the variable and name is the variable
// id is shown below as a RequestParam
@GetMapping("/system/resource")
// this is for swagger docs
@ApiOperation(value = "Get the resource identified by id and person")
ResponseEntity<?> getSomeResourceWithParameters(@RequestParam String id, @RequestParam("person") String name) {
InterestingResource resource = getMyInterestingResourc(id, name);
logger.info("Request to get an id of "+id+" with a name of person: "+name);
return new ResponseEntity<Object>(resource, HttpStatus.OK);
}