Spring 引导无法为 REST API 输入设置全局日期格式

Question

I am trying to set a global format for date-time, so that I don't have to annotate each and every method or on DTO fields.

I have tried to configure it globally, the only impact it had was on API response , it is formatting the date in specific pattern.

But it does not accept it as an input format.

@Configuration
public class DateFormatConfig {

    public DateFormatConfig() {
        TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
    }

    @Bean
    public Jackson2ObjectMapperBuilderCustomizer jsonCustomizer() {
        return builder -> {
            builder.simpleDateFormat("yyyy-MM-dd HH:mm:ss");
            builder.serializers(new LocalDateSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
            builder.serializers(new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        };
    }
}

Exception message

org.springframework.web.method.annotation.MethodArgumentTypeMismatchException: 
    Failed to convert value of type 'java.lang.String' to required type 'java.util.Date'; 
nested exception is org.springframework.core.convert.ConversionFailedException: 
    Failed to convert from type [java.lang.String] to type [@org.springframework.web.bind.annotation.RequestParam 
    java.util.Date] for value '2022-01-03 19:32:22'; nested exception is java.lang.IllegalArgumentException
....
Caused by: java.lang.IllegalArgumentException: null
    at java.base/java.util.Date.parse(Date.java:616) ~[na:na]
    at java.base/java.util.Date.<init>(Date.java:274) ~[na:na]
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:na]
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:490) ~[na:na]

A REST controller method where the call lands is as follow

public Response update(@PathVariable("id") 
                            Long id,
                       @RequestParam(value = "someTime", required = false) 
                            Date someTime)

My expectaion from above configuration is, it should work for both input and output of the API

1. It must accept the format I specificy for input
2. It must accept null as value

Everything works fine if I use @DateTimeFormat annotation , which means for each field I have to make such changes

@RequestParam(value = "someTime", required = false)
@DateTimeFormat(pattern = "yyyy-MM-dd HH:mm:ss") Date someTime

Answer 1

Can you try with below code.It should work.

@PostConstruct
    public void init() {
        // Setting Spring Boot SetTimeZone
        TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
    }

Answer 2

you should use

@Bean
public Converter<String, Date> stringDateConverter() {
    return new Converter<String, Date>() {
        final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

        @Override
        public Date convert(@NonNull String source) {
            return Date.from(formatter.parse(source, LocalDateTime::from).toInstant(ZoneOffset.UTC));
        }
    };
}

AbstractNamedValueMethodArgumentResolver#resolveArgument use WebDataBinder , WebDataBinder use ConversionService registered in WebMvcAutoConfiguration.EnableWebMvcConfiguration#mvcConversionService , and this converter will be registered in org.springframework.boot.convert.ApplicationConversionService#addBeans