@Nullable
    public static Double parseDoubleNullable(@Nonnull String s) {
        Objects.requireNonNull(s);
        try {
            return Double.parseDouble(s);
        } catch (NumberFormatException e) {
            return null;
        }
    }
Utility methods for parsing {@link Number}s, {@link Integer}s, {@link Long}s,
{@link Float}s and {@link Double}s from {@link String}s.
helper/src/main/java/me/lucko/helper/function/Numbers.java