Using JAXB with @XmlValue, @XmlElementRef and @XmlAdapter and keeping the order as received

Question

Disclaimer: This is just a very simple example. My scenario is much more complex than this.

Scenario:

My input XML:

<root>
  ...
  <element>
    Hello <name type="first">John</name>. Your policy number <policy number=1234/> has arrived.
    Please contact <contact brand="XPTO">999-9999</contact> for more information.
  </element>
  ...
</root>

My models: Root.java

@XmlRootElement(name = "root")
public class Root {
  @XmlElement
  protected Element element;

  ... (many other elements)
  //gets and sets
}

Element.java

@XmlRootElement(name = "element")
public class Element {

  @XmlElementRefs({
    @XmlElementRef(name = "name", type = Name.class, required = false),
    @XmlElementRef(name = "policy", type = Policy.class, required = false),
    @XmlElementRef(name = "contact", type = Contact.class, required = false),
  })
  @XmlJavaTypeAdapter(CommonElementAdapter.class)
  protected List<CommonElement> content;

  @XmlAnyElement
  @XmlMixed
  protected List<String> value;
  //gets and sets
}

Name/Policy/Contact.class (All of them has the very similar style)

@XmlRootElement(name = "name")
public class Name extends CommonElement {

  @XmlValue
  protected String value;

  @XmlAttribute
  protected String type;
  //gets and sets

  @Override
  public CommonElement unmarshal(CommonElement content) {
    //Do some stuff here with content. E.g.:
    content.setValue(content.getValue().toUpperCase());
    return content;
  }
}

CommonElement.java

@XmlTransient
public abstract class CommonElement {

    public CommonElement unmarshal (CommonElement value) {
        return value;
    }
}

CommonElementAdapter.java

public class CommonElementAdapter extends XmlAdapter<CommonElement, CommonElement> {

  @Override
  public CommonElement unmarshal(CommonElement content) throws Exception {
      return content.unmarshal(content); //Call the unmarshal for each element
  }

  @Override
  public CommonElement marshal(CommonElement content) throws Exception {
      return content;
  }
}

Expected result:

<root>
  ...
  <element>
    Hello <name type="first">JOHN</name>. Your policy number <policy number=1234/> has arrived.
    Please contact <contact brand="XPTO">999-9999</contact> for more information.
  </element>
  ...
</root>

Requirements:

The final text must be exactly as in the input XML, keeping the order as received.
The elements inside the tag must have it's on adapter. As my solution, it's inside the element itself, being called by CommonElementAdapter.
I CAN'T use MOXy or any other custom implementation.

My issue:

This way I put here, I can make all the text and elements appear in the result, but the order isn't correct. I'm getting something like this:

<element>
  <name type="first">JOHN</name>
  <policy number=1234/>
  <contact brand="XPTO">999-9999</contact>
  Hello . Your policy number has arrived.
  Please contact for more information.
</element>

I can change this removing the List<String> value from Element.java and changing the List<CommonElement> to List<Object>, so the value would be included at the content variable, keeping the order. But, this way, I couldn't make the Adapter work.

Using JAXB with @XmlValue, @XmlElementRef and @XmlAdapter and keeping the order as received

0 Answers0