How to use LocalDateTime RequestParam in Spring? I get “Failed to convert String to LocalDateTime”

Question

I use Spring Boot and included jackson-datatype-jsr310 with Maven:

    com.fasterxml.jackson.datatype         


        

Answer 1

I ran into the same problem and found my solution here (without using Annotations)

...you must at least properly register a string to [LocalDateTime] Converter in your context, so that Spring can use it to automatically do this for you every time you give a String as input and expect a [LocalDateTime]. (A big number of converters are already implemented by Spring and contained in the core.convert.support package, but none involves a [LocalDateTime] conversion)

So in your case you would do this:

public class StringToLocalDateTimeConverter implements Converter {
    public LocalDateTime convert(String source) {
        DateTimeFormatter formatter = DateTimeFormatter.BASIC_ISO_DATE;
        return LocalDateTime.parse(source, formatter);
    }
}

and then just register your bean:

With Annotations

add it to your ConversionService:

@Component
public class SomeAmazingConversionService extends GenericConversionService {

    public SomeAmazingConversionService() {
        addConverter(new StringToLocalDateTimeConverter());
    }

}

and finally you would then @Autowire in your ConversionService:

@Autowired
private SomeAmazingConversionService someAmazingConversionService;

You can read more about conversions with spring (and formatting) on this site. Be forewarned it has a ton of ads, but I definitely found it to be a useful site and a good intro to the topic.