Creating multiple @XmlRootElements from same Jaxb schema file

Question

I have the following JAXB .xsd schema file:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
       xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
       jaxb:version="2.1" xmlns="some.namespace.com"
       targetNamespace="some.namespace.com">

    <xs:element name="outerModel">
        <xs:annotation>
            <xs:appinfo>
                <jaxb:class name="OuterModelDto" />
            </xs:appinfo>
        </xs:annotation>
        <xs:complexType>
            <xs:sequence>
                <xs:element maxOccurs="unbounded" minOccurs="0" name="innerModel" type="innerModelDto" />
            </xs:sequence>
        </xs:complexType>
    </xs:element>

    <xs:complexType name="innerModelDto">
        <xs:sequence>
            <xs:element name="fullname" type="xs:string" />
            <xs:element name="surname" type="xs:string" />
        </xs:sequence>
        <xs:attribute name="id" type="xs:string" use="required" />
    </xs:complexType>
</xs:schema>

This will create an OuterModelDto and an InnerModelDto class. The OuterModelDto is annotated with @XmlRootElement, but the InnerModelDto is not. How can i ensure that InnerModelDto is also annotated with @XmlRootElement?

One solution was to wrap the innerModelDto complexType in an element, which meant that i did end up with @XmlRootElement on both Dtos, but during serialization of OuterModelDto, the namespace information was serialized, which i do not want.

score 1 · Answer 1 · answered Dec 04 '15 at 17:29

You can separate the complexType and element definitions in the schema. Each element will result in a @XmlRootElement annotation.

Make sure you declare some namespace prefix in your schema to be able to refer to the types, see the xmlns:tns here:

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
   jaxb:version="2.1"
   targetNamespace="some.namespace.com"
   xmlns:tns="some.namespace.com">

    <xs:complexType name="OuterModelDto">
        <xs:sequence>
            <xs:element maxOccurs="unbounded" minOccurs="0" name="innerModel" type="innerModelDto" />
        </xs:sequence>
    </xs:complexType>

    <xs:complexType name="InnerModelDto">
        <xs:sequence>
            <xs:element name="fullname" type="xs:string" />
            <xs:element name="surname" type="xs:string" />
        </xs:sequence>
        <xs:attribute name="id" type="xs:string" use="required" />
    </xs:complexType>

    <xs:element name="outerModel" type="tns:OuterModelDto" />
    <xs:element name="innterModel" type="tns:InnerModelDto" />

</xs:schema>

score 0 · Answer 2 · edited May 23 '17 at 11:59

You can use my jaxb2-annotate-plugin to annotate innerModelDto with @XmlRootElement. See (and upvote) this answer by Xstian:

https://stackoverflow.com/a/26545603/303810

The binding would be like:

<bindings node="xs:complexType[@type='innerModelDto']">
    <annox:annotateClass>@javax.xml.bind.annotation.XmlRootElement(name="innerModel")</annox:annotateClass>
</bindings>

Disclaimer: I am the author of the jaxb2-annotate-plugin.

Creating multiple @XmlRootElements from same Jaxb schema file

2 Answers2