13.9.2. Bind an Interceptor to a JAX-RS Method

@Provider
@ServerInterceptor
public class MyHeaderDecorator implements MessageBodyWriterInterceptor, AcceptedByMethod {

    public boolean accept(Class declaring, Method method) {
       return method.isAnnotationPresent(GET.class);
    }

   public void write(MessageBodyWriterContext context) throws IOException, WebApplicationException
   {
      context.getHeaders().add("My-Header", "custom");
      context.proceed();
   }
}