URI toUriWithKeys(String[] keys, final String... pathSegments) {
    return ServletUriComponentsBuilder.fromCurrentContextPath().path(getRestApiVersion())
        .pathSegment(pathSegments)
        .queryParam("keys", StringUtils.arrayToCommaDelimitedString(keys))
        .build(true).toUri();
  }
AbstractBaseController class contains common functionalities required for other controllers.

@since GemFire 8.0
geode-web-api/src/main/java/org/apache/geode/rest/internal/web/controllers/AbstractBaseController.java