#StackBounty: #java #spring #angular #spring-boot #spring-async Call async service which return DeferredResults, multiple times without…

Bounty: 200

my applications should have 2 core endpoints: push, pull for sending and fetching data.

Pull operation should works asynchronously and result DeferredResult. When user call pull service over rest, new DefferedResult is created and stored into Map<Long, DefferedResult> results = new ConcurrentHashMap<>() where is waiting for new data or until timeout is expired.

Push operation call user over rest as well, and this operation checks map of results for recipient of data pushed by this operation. When map contains result of recipient, these data are set to his result, DefferedResult is returned.

Here is base code:

public class FooServiceImpl {
    Map<Long, DefferedResult> results = new ConcurrentHashMap<>();

    public DeferredResult<String> pull(Long userId) {
        DeferredResult<String> newResult = new DeferredResult<>(5000L);
        results.putIfAbsent(userId, newResult);
        newResult.onCompletion(() -> results.remove(userId));
        return newResult;

    public void push(String data, Long recipientId) {
        if (results.containsKey(recipientId)) {

Code is working as I expected problem is that should also works for multiple users. I guess the max active users which will call pull operation will max 1000. So every call of pull take max 5 seconds as I set in DefferedResult but it isn’t.

As you can see in image, if I immediately call rest of pull operation from my javascript client multiple times you can see that tasks will executed sequentially instead of simultaneously. Tasks which I fired as last take about 25 seconds, but I need that when 1000 users execute at same time pull operation, that operation should take max 5 seconds + latency.

enter image description here

How to configure my app to execute these tasks simultaneously and ensure each each task will about 5 seconds or less (when another user send something to waiting user)? I tried add this configuration into property file:


and also this configuration:

public class AsyncConfig extends AsyncSupportConfigurer {

    protected AsyncTaskExecutor getTaskExecutor() {
        ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
        return taskExecutor;

But it didn’t help, still same result. Can you help me configure it please? Thanks in advice.


This is how I calling this service from angular:

this.http.get<any>(this.url, {params})
  .subscribe((data) => {
    console.log('s', data);
  }, (error) => {
    console.log('e', error);

When I tried call it multiple times with pure JS code like this:

function httpGet()
    var xmlHttp = new XMLHttpRequest();
    xmlHttp.open( "GET", 'http://localhost:8080/api/pull?id=1', true );
    xmlHttp.send( null );
    return xmlHttp.responseText;
setInterval(httpGet, 500);

it will execute every request call much faster (about 7 seconds). I expected that increasing is caused database calling in service, but it still better than 25 sec. Do I have something wrong with calling this service in angular?

Get this bounty!!!

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