CompletableFuture example (like javascript promises)

ThreadTestCompletableFuture.java

public class ThreadTest { 

    public static void main(String[] args) throws InterruptedException, ExecutionException {

        List<String> refs = new ArrayList<String>();
        refs.add("AA907");
        refs.add("H0704");
        refs.add("FD123");
        refs.add("DV067");
        
        List<CompletableFuture<ProductPivot>> list = new ArrayList<CompletableFuture<ProductPivot>>();
        for (String ref : refs) {
            
            list.add(CompletableFuture.supplyAsync(new Supplier<ProductPivot>() {
                
                @Override
                public ProductPivot get() {
            
                    RestTemplate template = new RestTemplate();
                    ResponseEntity<ProductPivot> product = template.getForEntity("http://myServer/v1/styles/" + ref, ProductPivot.class);
                    System.out.println("wake up !" + Thread.currentThread().getId());
                    return product.getBody();

                }

            }));
            
        }
        
        for (ProductPivot completableFuture : all(list).get()) {
            System.out.println(completableFuture.getTitle());
        }

    }
    
    public static <T> CompletableFuture<List<T>> all(List<CompletableFuture<T>> futures) {
        CompletableFuture[] cfs = futures.toArray(new CompletableFuture[futures.size()]);

        return CompletableFuture.allOf(cfs)
                .thenApply(v -> 
                    futures.stream().
                    map(CompletableFuture::join).
                    collect(Collectors.toList())
                );
    }

}