JAXB Mapping to JSON

Note: I'm the EclipseLink JAXB (MOXy) lead and a member of the JAXB (JSR-222) expert group.

If you can't do it with Jackson, you use case will work with MOXy.

Java Model

Foo

Here is a sample class that contains a field of type JAXBElement.

import javax.xml.bind.JAXBElement;import javax.xml.bind.annotation.*;@XmlAccessorType(XmlAccessType.FIELD)public class Foo {    @XmlElementRef(name="bar")    private JAXBElement<Bar> bar;}

Bar

public class Bar {}

ObjectFactory

import javax.xml.bind.JAXBElement;import javax.xml.bind.annotation.*;import javax.xml.namespace.QName;@XmlRegistrypublic class ObjectFactory {    @XmlElementDecl(name = "bar")    public JAXBElement<Bar> createBar(Bar bar) {        return new JAXBElement<Bar>(new QName("bar"), Bar.class, bar);    }}

Standalone Demo Code

Below is some demo code you can run in Java SE to see that everything works:

Demo

import java.util.*;import javax.xml.bind.*;import javax.xml.transform.stream.StreamSource;import org.eclipse.persistence.jaxb.JAXBContextProperties;public class Demo {    public static void main(String[] args) throws Exception {        Map<String, Object> properties = new HashMap<String, Object>(2);        properties.put(JAXBContextProperties.MEDIA_TYPE, "application/json");        properties.put(JAXBContextProperties.JSON_INCLUDE_ROOT, false);        JAXBContext jc = JAXBContext.newInstance(new Class[] {Foo.class, ObjectFactory.class}, properties);        Unmarshaller unmarshaller = jc.createUnmarshaller();        StreamSource json = new StreamSource("src/forum19158056/input.json");        Foo foo = unmarshaller.unmarshal(json, Foo.class).getValue();        Marshaller marshaller = jc.createMarshaller();        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);        marshaller.marshal(foo, System.out);    }}

input.json/Output

{"bar" : {} }

Running with JAX-RS

The following links will help you leverage MOXy in a JAX-RS service:

• http://blog.bdoughan.com/2012/05/moxy-as-your-jax-rs-json-provider.html
• http://blog.bdoughan.com/2013/06/moxy-is-new-default-json-binding.html

Since you're using Jackson you can construct an ObjectMapper with the JaxbAnnotationModule and write out the value. The following is some code to write a JAXB annotated object to system out.

ObjectMapper mapper = new ObjectMapper();mapper.registerModule(new JaxbAnnotationModule());        mapper.writeValue(System.out, jaxbObject);

This approach will also work on Glassfish as it does not utilize the provider given by the container which would cause ClassNotFoundException as per GLASSFISH-21141