Jak dostać Optional określonego typu?

    protected  <T> T getValueFromResultSet(ResultSet resultSet, String valueName, T defaultValue) {
        try {
            Optional<T> valueOpt = switch (defaultValue.getClass()) {
                case String.class -> Optional.ofNullable(resultSet.getString(valueName));
                case Integer.class -> Optional.ofNullable(resultSet.getInt(valueName));
                // inne typy
                default -> Optional.empty();
            };
            return valueOpt.orElse(defaultValue);
        } catch (SQLException e) {
            return defaultValue;
        }
    }

Incompatible types. Required Optional<T> but 'ofNullable' was inferred to Optional<T>:
no instance(s) of type variable(s) exist so that String conforms to T
inference variable T has incompatible bounds:
 equality constraints: T
lower bounds: String

public class PriceCodec extends Codec {
    private final String reservationTemplateId;
    private final String name;
    private final String description;
    private final String currencyCode; // TODO: Zmienić na typ waultowy
    private final int taxRate;
    private final BigDecimal defaultAmountNet;

    public PriceCodec(String id, int numericId, String reservationTemplateId, String name, String description,
                      String currencyCode, int taxRate, BigDecimal defaultAmountNet, LocalDateTime created) {
        super(id, numericId, created);
        this.reservationTemplateId = reservationTemplateId;
        this.name = name;
        this.description = description;
        this.currencyCode = currencyCode;
        this.taxRate = taxRate;
        this.defaultAmountNet = defaultAmountNet;
    }

    public static PriceCodec fromResultSet(ResultSet resultSet) throws SQLException {
        return new PriceCodec(
                resultSet.getString("id"),
                resultSet.getInt("numeric_id"),
                resultSet.getString("reservation_template_id"),
                resultSet.getString("name"),
                resultSet.getString("description"),
                resultSet.getString("currencyCode"),
                resultSet.getInt("tax_rate"),
                resultSet.getBigDecimal("default_amount_net"),
                resultSet.getTimestamp("created").toLocalDateTime()
        );
    }
// ...

@FunctionalInterface
interface ThrowingBiFunction<T, N, R, E extends Exception> {
    R apply(T t, N n) throws E;
}

protected <T> T getValueFromResultSet(ResultSet resultSet, String valueName, T defaultValue, ThrowingBiFunction<ResultSet, String, T, SQLException> extractor) {
        try {
            return Optional.ofNullable(extractor.apply(resultSet, valueName))
                    .orElse(defaultValue);
        } catch (SQLException e) {
            return defaultValue;
        }
    }

        String a = getValueFromResultSet(rs, "aaa", "test", ResultSet::getString);
        Integer b = getValueFromResultSet(rs, "bbb", 123, ResultSet::getInt);