What is @ParameterizedClass in JUnit 6 and how does it differ from @ParameterizedTest?

import org.junit.jupiter.params.ParameterizedClass;
import org.junit.jupiter.params.provider.MethodSource;
import org.junit.jupiter.api.*;

// @ParameterizedClass: the ENTIRE class runs once per argument
@ParameterizedClass
@MethodSource("locales")
@DisplayName("Cart service in locale")
class CartServiceLocaleTest {

    // Arguments injected via constructor or field
    private final Locale locale;

    CartServiceLocaleTest(Locale locale) {
        this.locale = locale;
    }

    static Stream<Locale> locales() {
        return Stream.of(Locale.US, Locale.UK, Locale.DE);
    }

    @Test
    void currencySymbolIsCorrect() {
        CartService svc = new CartService(locale);
        assertNotNull(svc.getCurrencySymbol());
    }

    @Test
    void priceFormattingMatchesLocale() {
        CartService svc = new CartService(locale);
        String price = svc.format(9.99);
        assertTrue(price.contains(svc.getCurrencySymbol()));
    }
}
// Runs 2 tests x 3 locales = 6 test invocations total

// Compare with @ParameterizedTest (method-level):
class CartServiceTest {
    @ParameterizedTest
    @MethodSource("locales")
    void currencySymbolIsCorrect(Locale locale) {  // single method only
        assertNotNull(new CartService(locale).getCurrencySymbol());
    }
}