presto-spi/src/main/java/io/prestosql/spi/security/SelectedRole.java/SelectedRole/valueOf
class SelectedRole:    public static SelectedRole valueOf(String value)
    {
        Matcher m = PATTERN.matcher(value);
        if (m.matches()) {
            Type type = Type.valueOf(m.group(1));
            Optional<String> role = Optional.ofNullable(m.group(3));
            return new SelectedRole(type, role);
        }
        throw new IllegalArgumentException("Could not parse selected role: " + value);
    }