AsyncRestTemplate not calling DELETE endpoint

Question

I need to call rest endpoint with delete method in fire and forget fashion. I don't care about result. I am trying to use AsyncRestTemplate but server side is not being called. If I switch to RestTemplate everything works. Then I have noticed that when I wait for response

AsyncRestTemplate template = new AsyncRestTemplate();
ListenableFuture<ResponseEntity<String>> exchange = template.exchange(
    url, 
    HttpMethod.DELETE, 
    new HttpEntity<Object>(headers), 
    String.class
);
exchange.get();

it is also working. Calling PUT endpoint works without any problems (don't have to call get() method). Then, I tried to use timeout since I don't want to wait for response and used

    try {
        exchange.get(1, TimeUnit.MILLISECONDS);
    } catch (InterruptedException | ExecutionException | TimeoutException e) {
        //dirty hack
    }

On my machine if I set 1 millisecond timeout there is a 50% chance that endpoint gets called. At 50 millis it gets too 100% chance...

Any ideas what's the problem?

EDIT:

I also tried

CompletableFuture.runAsync(() -> {
    try {
        exchange.get();
    } catch (InterruptedException | ExecutionException e) {
        e.printStackTrace();
    }
});

which has worked.

AsyncRestTemplate template = new AsyncRestTemplate(
     new ConcurrentTaskExecutor(Executors.newCachedThreadPool())
);

without calling get() method did not work.

Answer 1

If you set 1 ms timeout it is very likely that request will in fact timeout, but also client will terminate the connection while handling the timeout.

Try calling it in a thread or create an ExecutorService and queue up the requests.