泽西岛-XmlRootElement /实体的返回列表-找不到MessageBodyWriter

Question

There are a million of these JAX-RS serialization snowflakes. Let me add one more.

I have a JPA/JAXb annotated class:

@Entity
@XmlRootElement
public class Foo implements Serializable {
//..
}

I have a service that seeks to return a list of these objects as JSON:

@Path("foo")
public class FooService {

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public Response listFoos() {
        // get hibernate session
        List<Foo> foos = session.createQuery("from Foo").list();
        GenericEntity<List<Foo>> entity = new GenericEntity<List<Foo>>(foos) {};
        return Response.ok(entity).build();
    }
}

I have tried a number of variations. The one that looks the best, to me is like

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public List<Foo> listFoos() {
        // get session ..
        return session.createQuery("from Foo").list();
    }

All give me some slight variation of:

SEVERE: MessageBodyWriter not found for
media type=application/json, type=class java.util.ArrayList, 
genericType=java.util.List<com.bar.baz.Foo>.

Answer 1

Don't forget to add a dependency like:

    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-moxy</artifactId>
    </dependency>