public void addServerInstance(ServerInstance serverInstance) {
            Objects.requireNonNull(serverInstance, "serverInstance");

            List<ServerInstance> find = getServerGroupList0(serverInstance.getHostName());
            addServerInstance(find, serverInstance);
        }
@author emeroad
@author netspider
@author minwoo.jung
@author HyunGil Jeong
web/src/main/java/com/navercorp/pinpoint/web/applicationmap/nodes/ServerGroupList.java