Spring mvc controller

```
@RequestMapping(method = RequestMethod.POST)
public Result<String> create(CouponModel model) {//...}

CuponModel:
private Date beginDate;
private Date overDate;

```

when call this api

```
curl -X POST -d '...&beginDate=1459500407&overDate=1459699200' 'http://localhost:8080/coupons'
Error 400 Bad Request

```

first nothing error log output, then changed to `debug` level, ouput

```
Field error in object 'couponModel' on field 'beginDate': rejected value [1459500407]; codes [typeMismatch.couponModel.beginDate,typeMismatch.beginDate,typeMismatch.java.util.Date,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [couponModel.beginDate,beginDate]; arguments []; default message [beginDate]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'java.util.Date' for property 'beginDate'; nested exception is org.springframework.core.convert.ConversionFailedException: Failed to convert from type java.lang.String to type @javax.validation.constraints.NotNull java.util.Date for value '1459500407'; nested exception is java.lang.IllegalArgumentException]

```

How to let parameter long convert to date in model?

I tried below way but it does not work

```
public class StringToDateConverter implements Converter<String, Date> {

    @Override
    public Date convert(String source) {
        if (source == null ) {
            return null;
        }
        return new Date(Long.valueOf(source));
    }

}

@Configuration
@EnableWebMvc
public class WebMvcContext extends WebMvcConfigurerAdapter {
    @Override
    public void addFormatters(FormatterRegistry registry) {
         registry.addConverter(new StringToDateConverter());
    }
}

```