cxf wsdl2java optional and required elements

Question

I use CXF to generate java code from a 3rd party wsdl (not maintained by us).

I have this two snippets working not as expected when marshalling to soap message.

XML:
<choice>
  <sequence>
    <element name="x" type="xt" nillable="true" minOccurs="0" />
  </sequence>
  <element name="y" type="yt" 
     nillable="true" minOccurs="0" />
</choice>

Java:
@XmlElement(name = "x", nillable = true)
protected Xx;
@XmlElement(name = "y", nillable = true)
protected Y y;

If I add x, but not y to the soap message (via code) then it looks like:

<x>123456782</x>
<y xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  xsi:nil="true" />

Why is it adding y to the soap message, while it's an optional element?

Something similar is happening with this snippet:

XML:
<attribute ref="z" use="required" fixed="XXX" />

Java:
@XmlAttribute(name = "z", namespace = "http://www.egem.nl/StUF/StUF0301",
  required = true)
protected String z;

Here cxf (with schema validation on true) complains if I don't add the element via code. If i turn of the schema validation then is not creating the element add all.

This element is required and has a fixed attribute, why isn't it creating it if i don't add it (via code)?

EDIT: During development i realized that cxf was generating a .package-info.java file, which gave me trouble with namespaces. So I was searching for a way disable the generation of .package-info.java file. The solution for that was to put an extraarg to cxf codegen plugin: -xjc-npa in the pom file. That part in the pom looks like:

<plugin>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-codegen-plugin</artifactId>
    <version>${cxf.version}</version>
    <configuration>
        <defaultOptions>
            <extraargs>                 
                <extraarg>-xjc-npa</extraarg>
            </extraargs>
        </defaultOptions>
    </configuration>
</plugin>

But to my surprise after re-generating the class files, was that all fixed elements are now constants. No more getters/setters generated. But unfortunately the problem with the choices remains.

Answer 1

Apparently i was reading old documentation. All I had to do was adding the below attributes to jaxb:globalBindings in the binding file.

In the old documentation there was no mention of these attributes.

<jaxb:globalBindings fixedAttributeAsConstantProperty="true" choiceContentProperty="true">

With these attributes all fixed attributes in the xml are now enums and all choice elements in the xml are now better generated in the code (in the xxxOrxxxOrxxx format).