As the exception states you're not going to be able to map a property of type Iterable
with @XmlElementWrapper
.
Exception in thread "main" javax.xml.bind.JAXBException:
Exception Description: XmlElementWrapper is only allowed on a collection or array property but [movies] is not a collection or array property.
- with linked exception:
[Exception [EclipseLink-50015] (Eclipse Persistence Services - @VERSION@.@QUALIFIER@): org.eclipse.persistence.exceptions.JAXBException
Exception Description: XmlElementWrapper is only allowed on a collection or array property but [movies] is not a collection or array property.]
at org.eclipse.persistence.jaxb.JAXBContext$TypeMappingInfoInput.createContextState(JAXBContext.java:1068)
at org.eclipse.persistence.jaxb.JAXBContext.<init>(JAXBContext.java:182)
XmlAdapter (MoviesAdapter)
Instead we are going to use an XmlAdapter
to convert Iterable
into something we can map. In this case an instance of a class we'll make up called Movies
that has a List
of Movie
instances.
package test.moxy;
import java.util.*;
import javax.xml.bind.annotation.adapters.XmlAdapter;
public class MoviesAdapter extends XmlAdapter<MoviesAdapter.Movies, Iterable<Movie>> {
public static class Movies {
public List<Movie> movie = new ArrayList<Movie>();
}
@Override
public Iterable<Movie> unmarshal(Movies v) throws Exception {
return v.movie;
}
@Override
public Movies marshal(Iterable<Movie> v) throws Exception {
Movies movies = new Movies();
for(Movie movie : v) {
movies.movie.add(movie);
}
return movies;
}
}
External Metadata (oxm.xml)
Below is the modified oxm.xml
that references the XmlAdapter
. With the new mappings the Movies
object will cause the movies
element to come into existence so we won't need the @XmlElementWrapper
metadata anymore.
<?xml version="1.0" encoding="UTF-8"?>
<xml-bindings xmlns="http://www.eclipse.org/eclipselink/xsds/persistence/oxm"
package-name="test.moxy" xml-mapping-metadata-complete="true">
<java-types>
<java-type name="Actor">
<xml-root-element name="actor" />
<xml-type prop-order="name movies" factory-class="test.moxy.ProxyFactory"
factory-method="initActor" />
<java-attributes>
<xml-element java-attribute="name" />
<xml-element java-attribute="movies">
<xml-java-type-adapter value="test.moxy.MoviesAdapter"/>
</xml-element>
</java-attributes>
</java-type>
<java-type name="Movie">
<xml-root-element name="movie" />
<xml-type factory-class="test.moxy.ProxyFactory"
factory-method="initMovie" />
<java-attributes>
<xml-element java-attribute="title" />
</java-attributes>
</java-type>
</java-types>
</xml-bindings>