Prefixing JAXB generated classes

Question

I have this Maven "task" to generate Java classes from an XSD file using JAXB.

        <!-- XML to Java classes -->
        <plugin>
            <groupId>com.sun.tools.xjc.maven2</groupId>
            <artifactId>maven-jaxb-plugin</artifactId>
            <executions>
                <execution>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>generate</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <generatePackage>nl.compay.service</generatePackage>
                <schemaDirectory>src/main/webapp/compay</schemaDirectory>
            </configuration>
        </plugin>

For an XSD type "User", it generates a class named "User" (duh). However, I also have a JPA entity class called "User" (though in a different package). Can I change the XML config above to let JAXB prefix the generated classes with something like "XML"?

Answer 1

This is a common requirement. You can do that by providing an additional JAXB binding file to customize how JAXB translates the Schema type names into Java class names.

These files normally end in extension ".xjb". You need to create one for your schema, for example:

<jxb:bindings version="1.0" 
  xmlns:jxb="http://java.sun.com/xml/ns/jaxb" 
  xmlns:xs="http://www.w3.org/2001/XMLSchema" 
  xmlns:xjc="http://java.sun.com/xml/ns/jaxb/xjc" 
  jxb:extensionBindingPrefixes="xjc">

    <jxb:bindings schemaLocation="nl.company.service.xsd" node="/xs:schema">
        <jxb:schemaBindings>
            <jxb:nameXmlTransform>
                <jxb:typeName prefix="XML"/>
                <jxb:anonymousTypeName prefix="XML"/>
            </jxb:nameXmlTransform>
        </jxb:schemaBindings>
    </jxb:bindings>

</jxb:bindings>

After you've done that, drop the xjb file somewhere in your build directory and tell Maven to make use of it during translation:

<includeBindings>
    <includeBinding>mybindings.xjb</includeBinding>
</includeBindings>

And here's a hint for the road: if you are in a path that contains spaces (e.g. "Documents and Settings\user\project") then JAXB will fall over with strange errors.