@Override
            public void serverStopping(Server server) {
                // NOT_SERVING will be sent to clients by changing a healthiness of a server
                serverHealth.setHealthy(false);
                synchronized (watchers) {
                    watchers.values().forEach(StreamObserver::onCompleted);
                    watchers.clear();
                }
            }
Returns a new builder which builds a new {@link GrpcHealthCheckService}.
grpc/src/main/java/com/linecorp/armeria/server/grpc/GrpcHealthCheckService.java