How to convert XMLGregorianCalendar to Date to XMLGregorianCalendar in Java - Example Tutorial

To convert an XMLGregorianCalendar to a Date and then back to an XMLGregorianCalendar in Java, you can follow these steps:

1. Import the necessary classes:

import java.util.Date;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

2. Convert XMLGregorianCalendar to Date:

public Date convertXMLGregorianCalendarToDate(XMLGregorianCalendar xmlCalendar) {
    return xmlCalendar.toGregorianCalendar().getTime();
}

3. Convert Date to XMLGregorianCalendar:

public XMLGregorianCalendar convertDateToXMLGregorianCalendar(Date date) throws Exception {
    GregorianCalendar calendar = new GregorianCalendar();
    calendar.setTime(date);
    return DatatypeFactory.newInstance().newXMLGregorianCalendar(calendar);
}

Here's an example that demonstrates the conversion:

import java.util.Date;
import java.util.GregorianCalendar;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

public class XMLGregorianCalendarConversionExample {

    public static void main(String[] args) {
        try {
            // Create an XMLGregorianCalendar object representing a date
            XMLGregorianCalendar xmlCalendar = DatatypeFactory.newInstance().newXMLGregorianCalendarDate(2023, 5, 25, 0);

            // Convert XMLGregorianCalendar to Date
            Date date = convertXMLGregorianCalendarToDate(xmlCalendar);
            System.out.println("XMLGregorianCalendar to Date: " + date);

            // Convert Date to XMLGregorianCalendar
            XMLGregorianCalendar convertedCalendar = convertDateToXMLGregorianCalendar(date);
            System.out.println("Date to XMLGregorianCalendar: " + convertedCalendar);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static Date convertXMLGregorianCalendarToDate(XMLGregorianCalendar xmlCalendar) {
        return xmlCalendar.toGregorianCalendar().getTime();
    }

    public static XMLGregorianCalendar convertDateToXMLGregorianCalendar(Date date) throws Exception {
        GregorianCalendar calendar = new GregorianCalendar();
        calendar.setTime(date);
        return DatatypeFactory.newInstance().newXMLGregorianCalendar(calendar);
    }
}

In this example, we create an XMLGregorianCalendar object representing the date May 25, 2023. We then convert it to a Date object using the convertXMLGregorianCalendarToDate method and print the result. 

Next, we convert the Date object back to an XMLGregorianCalendar using the convertDateToXMLGregorianCalendar method and print the result. 

Note: The convertDateToXMLGregorianCalendar method throws an exception of type Exception. In a real application, you should handle or propagate this exception as appropriate.