ObjectFactory Demo

ObjectFactory.java

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlElementDecl;
import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.namespace.QName;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;

/**
 * @author <a href="mailto:l.weinan@gmail.com">Weinan Li</a>
 */
@XmlRegistry
public class ObjectFactory {

    private static class Bar {
        private int x;

        public int getX() {
            return x;
        }

        public void setX(int x) {
            this.x = x;
        }
    }

    @XmlElementDecl(name = "barbar")
    public JAXBElement<Bar> createBar(Bar bar) {
        return new JAXBElement<Bar>(new QName("barbar"), Bar.class, bar);
    }

    public static void main(String[] args) throws Exception {
        Bar bar = new Bar();
        bar.setX(1);

        JAXBContext ctx = JAXBContext.newInstance(ObjectFactory.class);

        Unmarshaller um = ctx.createUnmarshaller();
        InputStream stream = new ByteArrayInputStream("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?><barbar><x>1</x></barbar>\n".getBytes(StandardCharsets.UTF_8));

        JAXBElement<Bar> barElem = (JAXBElement<Bar>) um.unmarshal(stream);
        System.out.println(barElem.getValue().getX());

    }
}