关于nacos-client中的HostReactor的一点疑问

最近在学习Nacos相关的源码中，在com.alibaba.nacos:nacos-client:1.4.0中, com.alibaba.nacos.client.naming.core.HostReactor.getServiceInfo:261行

if (null == serviceObj) { serviceObj = new ServiceInfo(serviceName, clusters);

        serviceInfoMap.put(serviceObj.getKey(), serviceObj);
        
        updatingMap.put(serviceName, new Object());
        updateServiceNow(serviceName, clusters);
        updatingMap.remove(serviceName);
        
    } else if (updatingMap.containsKey(serviceName)) {

当有新的服务注册的时候，我发现此处 serviceInfoMap 若不存在该新服务，仍然会将服务信息put到 serviceInfoMap 中去，这将导致 HostReacot.processServiceJson(json) 中 oldService != null 的判断恒为 真

public ServiceInfo processServiceJson(String json) { ServiceInfo serviceInfo = JacksonUtils.toObj(json, ServiceInfo.class); ServiceInfo oldService = serviceInfoMap.get(serviceInfo.getKey()); if (serviceInfo.getHosts() == null || !serviceInfo.validate()) { //empty or error push, just ignore return oldService; }

    boolean changed = false;
    
    if (oldService != null) {
        
        if (oldService.getLastRefTime() > serviceInfo.getLastRefTime()) {
            NAMING_LOGGER.warn("out of date data received, old-t: " + oldService.getLastRefTime() + ", new-t: "
                    + serviceInfo.getLastRefTime());
        }
        
        serviceInfoMap.put(serviceInfo.getKey(), serviceInfo);

当然，我并没有完全读懂整个代码的逻辑，但是我希望有人能给我解释一下。不胜感激

原提问者GitHub用户VincentCh01