I am having some issues with generating Java Classes with appropriate JAXB annotations from an XSD using XJC.
I have a relatively simple XSD file defining my XML schema. The complex types within the XSD take advantage of inheritance using the <xs:extension>
tags. The problem I having is that I need all complex types to generate Java Classes with the @XmlRootElement
.
Unfortunately, the way in which XJC generates the classes means that only derived class gets the @XmlRootElement
(not the base class). I am using the simple global binding directive to ensure that it solves many of the other issues that I have faced with XJC.
Here is an example snippet of the XSD:
<xs:schema version="1.0" targetNamespace="http://www.knowledgemill.com/kmcs"
xmlns:kmcs="http://www.knowledgemill.com/kmcs"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
jaxb:version="2.0"
xmlns:xjc="http://java.sun.com/xml/ns/jaxb/xjc"
jaxb:extensionBindingPrefixes="xjc"
elementFormDefault="qualified">
<xs:annotation>
<xs:appinfo>
<jaxb:globalBindings>
<xjc:simple />
</jaxb:globalBindings>
</xs:appinfo>
</xs:annotation>
<xs:element name="Artifact" type="kmcs:Artifact"/>
<xs:element name="EmailArtifact" type="kmcs:EmailArtifact"/>
<xs:complexType name="Artifact">
<xs:sequence>
<xs:element name="artifactId" type="xs:string" minOccurs="0"/>
<xs:element name="artifactType" type="xs:string" minOccurs="0"/>
<xs:element name="contentHash" type="xs:string" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="EmailArtifact">
<xs:complexContent>
<xs:extension base="kmcs:Artifact">
<xs:sequence>
<xs:element name="subject" type="xs:string" minOccurs="0"/>
<xs:element name="threadSubject" type="xs:string" minOccurs="0"/>
<xs:element name="from" type="xs:string" minOccurs="0"/>
<xs:element name="to" type="xs:string" minOccurs="0"/>
<xs:element name="cc" type="xs:string" minOccurs="0"/>
<xs:element name="bcc" type="xs:string" minOccurs="0"/>
<xs:element name="messageId" type="xs:string" minOccurs="0"/>
<xs:element name="date" type="xs:date" minOccurs="0"/>
<xs:element name="size" type="xs:long" minOccurs="0"/>
<xs:element name="hasAttachment" type="xs:boolean" minOccurs="0"/>
<xs:element name="sensitivity" type="xs:string" minOccurs="0"/>
<xs:element name="headerHash" type="xs:string" minOccurs="0"/>
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
</xs:schema>
As we can see from the above snippet, EmailArtifact
extends Artifact
.
The java class code for EmailArtifact
contains the following:
@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "EmailArtifact", propOrder = {
"subject",
"threadSubject",
"from",
"to",
"cc",
"bcc",
"messageId",
"date",
"size",
"hasAttachment",
"sensitivity",
"headerHash"
})
@XmlSeeAlso({
ExtendedEmail.class
})
@XmlRootElement(name = "EmailArtifact")
public class EmailArtifact
extends Artifact
{
protected String subject;
protected String threadSubject;
protected String from;
protected String to;
protected String cc;
protected String bcc;
protected String messageId;
@XmlSchemaType(name = "date")
protected XMLGregorianCalendar date;
protected Long size;
protected Boolean hasAttachment;
protected String sensitivity;
protected String headerHash;
The java class code for Artifact
contains the following:
@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "Artifact", propOrder = {
"artifactId",
"artifactType",
"contentHash"
})
@XmlSeeAlso({
ManagedDocArtifact.class,
EmailArtifact.class
})
public class Artifact {
protected String artifactId;
protected String artifactType;
protected String contentHash;
In the EmailArtifact
we can see that it contains the @XmlRootElement
but the base type Artifact
does not contain @XmlRootElement
.
How can you force XJC to generate @XmlRootElement
for all classes including the base types.
Just bind using xjb-file:
<?xml version="1.0"?>
<jxb:bindings version="1.0" xmlns:jxb="http://java.sun.com/xml/ns/jaxb" xmlns:xjc="http://java.sun.com/xml/ns/jaxb/xjc" jxb:extensionBindingPrefixes="xjc" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<jxb:bindings schemaLocation="path/to/myschema.xsd" node="/xs:schema">
<jxb:globalBindings>
<xjc:simple />
</jxb:globalBindings>
</jxb:bindings>
</jxb:bindings>
And don't forget to define element of the same type:
<xs:complexType name="Artifact" />
<xs:element name="artifact" type="Artifact">