requestParam 得到 null，因为 queryParam 发送字符串值

Question

从这里发送

UriComponentsBuilder builder =
UriComponentsBuilder.
fromUriString(mobileAnalyticsModuleUrl + "/avgsessionduration")

                    .queryParam("studyId", studyId)
                    .queryParam("clientId", clientId);
            if (siteId != null) {
                builder.queryParam(siteId).queryParam("isDefaultSiteOfStudy", isDefaultSiteOfStudy);
            }

Controller

public HashMap<String, Integer> getAvgSessionDurationRedShiftData(@RequestParam(value = "studyId") String studyId,

            @RequestParam(value = "siteId", required = false) String siteId,
            @RequestParam(value = "isDefaultSiteOfStudy", required = false) boolean isDefaultSiteOfStudy,
            @RequestParam(value = "clientId") String clientId) throws Exception {