public static SamlNameIdPolicy of(SamlNameIdFormat format, boolean isCreatable) {
        requireNonNull(format, "format");
        return new SamlNameIdPolicy(format, isCreatable);
    }
Returns a {@link SamlNameIdPolicy} with the specified {@link SamlNameIdFormat} and
{@code isCreatable}.
saml/src/main/java/com/linecorp/armeria/server/saml/SamlNameIdPolicy.java