HTTP Content Negotiation - RESTful Java with JAX-RS 2.0 - page 137

That's a lot of code to say that the getSomething() JAX-RS method supports XML, JSON,
English, Spanish, deflated, and GZIP encodings. You're almost better off not using the se-
lectVariant() API and doing the selection manually. Luckily, JAX-RS offers the
javax.ws.rs.core.Variant.VariantListBuilder class to make writing these complex
selections easier:

public public static static abstract abstract class class VariantListBuilder VariantListBuilder {

public public static static VariantListBuilder newInstance () {...}

public public abstract abstract VariantListBuilder mediaTypes ( MediaType ... mediaTypes );

public public abstract abstract VariantListBuilder languages ( Locale ... languages );

public public abstract abstract VariantListBuilder encodings ( String ... encodings );

public public abstract abstract List < Variant > build ();

public public abstract abstract VariantListBuilder add ();

}

The VariantListBuilder class allows you to add a series of media types, languages, and
encodings to it. It will then automatically create a list of variants that contains every possible
combination of these objects. Let's rewrite our previous example using a Vari-
antListBuilder :

@Path ( "/myservice" )
public

public class class MyService MyService {

@GET
Response getSomething ( @Context Request request ) {

Variant . VariantListBuilder vb = Variant . VariantListBuilder . newInstance ();
vb . mediaTypes ( MediaType . APPLICATION_XML_TYPE ,
MediaType . APPLICATION_JSON_TYPE )

. languages ( new new Locale ( "es" ))

. encodings ( "deflate" , "gzip" ). add ();

new Locale ( "en" ), new

List < Variant > variants = vb . build ();

// Pick the variant
Variant v = request . selectVariant ( variants );
Object entity = ...; // get the object you want to return

ResponseBuilder builder = Response . ok ( entity );