Spring deserializes a LocalDate in a @RequestBody differently from one in a @RequestParam - why, and can they be the same?

Question

QUESTION: Spring appears to use different deserialization methods for LocalDate depending on whether it appears in a @RequestBody or a request @R

Answer 1

Create a Formatter for LocalDate:

public class LocalDateFormatter implements Formatter {

    @Override
    public LocalDate parse(String text, Locale locale) throws ParseException {
        return LocalDate.parse(text, DateTimeFormatter.ISO_DATE);
    }

    @Override
    public String print(LocalDate object, Locale locale) {
        return DateTimeFormatter.ISO_DATE.format(object);
    }
}

Spring 5+: Register the formatter: Implement WebMvcConfigurer in your @Configuration and override addFormatters:

@Override
public void addFormatters(FormatterRegistry registry) {
    registry.addFormatter(new LocalDateFormatter());
}

Spring Boot: Define a @Primary @Bean to override the default formatter:

@Bean
@Primary
public Formatter localDateFormatter() {
    return new LocalDateFormatter();
}