CompletableFuture eventual race condition

I sorry for posting in list, but I need an authoritative answer. I was told by one of the developers of another JVM (Ceylon) language that CompletableFuture.supplyAsync(() -> "Hejjo Worjd from Java") .thenApply(s -> s.replaceAll("j","l")) .thenAccept(System.out::println); would eventual fail to print if run enough times. Is this true?