@PreDestroy
    public void close() {
        if (checked) {
            if (Objects.nonNull(scheduledFuture)) {
                scheduledFuture.cancel(false);
            }
            if (Objects.nonNull(executor)) {
                executor.shutdown();
            }
        }
    }
Close relative resource on container destroy.
shenyu-admin/src/main/java/org/apache/shenyu/admin/service/impl/UpstreamCheckService.java