Implementing Custom Type Converters for Spring Data ConversionService

public record IsoCurrency(String currencyCode, int fractionDigits) {}
 
@Component
public class StringToIsoCurrencyConverter implements Converter<String, IsoCurrency> {
 
    @Override
    public IsoCurrency convert(String source) {
        if (source == null || source.isBlank()) {
            return null;
        }
        String normalized = source.trim().toUpperCase();
        Currency currency = Currency.getInstance(normalized);
        return new IsoCurrency(currency.getCurrencyCode(), currency.getDefaultFractionDigits());
    }
}
 
@Configuration
public class WebFormattingConfiguration implements WebMvcConfigurer {
    @Override
    public void addFormatters(FormatterRegistry registry) {
        registry.addConverter(new StringToIsoCurrencyConverter());
    }
}