Convert GregorianCalendar to XMLGregorianCalendar

问题

While working with legacy code not yet updated for the modern java.time classes, I need to convert a ZonedDateTime to XMLGregorianCalendar. So I thought I'd go by way of GregorianCalendar, calling GregorianCalendar.from( ZonedDateTime ).

I see methods for going from XMLGregorianCalendar to GregorianCalendar: XMLGregorianCalendar::toGregorianCalendar.

➥ I need the opposite, going from GregorianCalendar to XMLGregorianCalendar.

回答1:

DatatypeFactory.newInstance().newXMLGregorianCalendar( … )

While neither the XMLGregorianCalendar nor GregorianCalendar classes offer the conversion method you need, there is a workaround.

A javax.xml.datatype.DatatypeFactory object can convert from GregorianCalendar to XMLGregorianCalendar by calling its newXMLGregorianCalendar method.

XMLGregorianCalendar xmlGregCal = 
        DatatypeFactory
        .newInstance()
        .newXMLGregorianCalendar( gregCal ) 
;

---

To complete the entire cascade you mentioned, from java.time.ZonedDateTime to GregorianCalendar to XMLGregorianCalendar.

XMLGregorianCalendar xmlGregCal = 
        DatatypeFactory
        .newInstance()
        .newXMLGregorianCalendar( 
            GregorianCalendar
            .from(
                myZonedDateTime
            )
        ) 
;

来源：https://stackoverflow.com/questions/59257517/convert-gregoriancalendar-to-xmlgregoriancalendar