public static CompletionStage combineFutures()

in src/main/java/com/spotify/futures/CompletableFutures.java [661:674]

• 13 lines of code
• 1 McCabe index (conditional complexity)

  public static <R, A, B, C, D> CompletionStage<R> combineFutures(
      CompletionStage<A> a,
      CompletionStage<B> b,
      CompletionStage<C> c,
      CompletionStage<D> d,
      Function4<A, B, C, D, CompletionStage<R>> function) {
    final CompletableFuture<A> af = a.toCompletableFuture();
    final CompletableFuture<B> bf = b.toCompletableFuture();
    final CompletableFuture<C> cf = c.toCompletableFuture();
    final CompletableFuture<D> df = d.toCompletableFuture();

    return CompletableFuture.allOf(af, bf, cf, df)
        .thenCompose(ignored -> function.apply(af.join(), bf.join(), cf.join(), df.join()));
  }