Question

I’m rather new to JAXB and have come across a problem which I can’t seem to fix.

If I have a simple XML file as follows.

<Root>
    <Test>TestStuff</Test>
</Root>

I would like to create a class to handle “root” and another to handle “test”. I know normally you wouldn’t do this but for this example here’s the classes I created;

@XmlRootElement
class MyElement {
    private String test;
    @XmlElement(name="Test")
    public String getTest() { return test; }
    public void setTest(String test) { this.test = test; }  
}

@XmlRootElement(name="Root")
class Root {
    private MyElement myElement;
    public MyElement getMyElement() { return myElement; }
    public void setMyElement(MyElement myElement) { this.myElement = myElement; }
}

When I run the code below I always get null for myElement.

@Test
public void testJAXB() throws Exception {
    InputStream xmlInputStream = new FileInputStream(new File(".\\files\\test1.xml"));           
    JAXBContext context = JAXBContext.newInstance(Root.class, MyElement.class);
    Unmarshaller um = context.createUnmarshaller();
    Root root = (Root) um.unmarshal(xmlInputStream);

    Assert.assertTrue(root.getMyElement().getTest().equals("TestStuff"));          
}

Could someone point me in the right direction regarding this?
Thanks.

Answer 1

You could do the following leveraging @XmlElement and @XmlValue:

Root

@XmlRootElement(name="Root")
class Root {
    private MyElement myElement;

    @XmlElement(name="Test")
    public MyElement getMyElement() { return myElement; }
    public void setMyElement(MyElement myElement) { this.myElement = myElement; }
}

MyElement

class MyElement {
    private String test;

    @XmlValue
    public String getTest() { return test; }
    public void setTest(String test) { this.test = test; }  
}

For More Information

• http://blog.bdoughan.com/2011/06/jaxb-and-complex-types-with-simple.html

---

UPDATE

If you are using EclipseLink MOXy (I’m the tech lead) as your JAXB provider you can use the @XmlPath(".") extension to map this use case.

Root

import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.XmlPath;

@XmlRootElement(name="Root")
class Root {
    private MyElement myElement;

    @XmlPath(".")
    public MyElement getMyElement() { return myElement; }
    public void setMyElement(MyElement myElement) { this.myElement = myElement; }
}

MyElement

class MyElement {
    private String test;

    @XmlElement(name="Test")
    public String getTest() { return test; }
    public void setTest(String test) { this.test = test; }  
}

For More Information

• http://blog.bdoughan.com/2010/07/xpath-based-mapping.html
• http://blog.bdoughan.com/2011/05/specifying-eclipselink-moxy-as-your.html