@NotNull
  private static Map<Integer, TraceElement> difference(@NotNull Collection<TraceElement> before, @NotNull Set<Integer> timesAfter) {
    return makeIndexByTime(before.stream().filter(x -> !timesAfter.contains(x.getTime())));
  }
@NotNull
  private static Map<Integer, TraceElement> difference(@NotNull Collection<TraceElement> before, @NotNull Set<Integer> timesAfter)