Comparison Java + JAX-RS vs. Java + Playframework 2 vs. Scala + Playframework 2

JaxRsResource.java

package se;

import com.sun.jersey.api.NotFoundException;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.CacheControl;
import javax.ws.rs.core.EntityTag;
import javax.ws.rs.core.Response;
import java.util.Collection;

@Path(value = "/recept")
@Produces("application/json")
public class ReceptResource {

    @GET
    public Collection<ReceptRepository.Recept> all() {
        return ReceptRepository.all();
    }

    @GET
    @Path("/{id}")
    public Response get(@PathParam("id") int id){
        ReceptRepository.Recept recept = ReceptRepository.get(id);
        if(recept == null){
            throw new NotFoundException("Recept id " +id + " finns inte");
        }
        CacheControl cacheControl = new CacheControl();
        cacheControl.setMaxAge(3600);
        EntityTag eTag = new EntityTag("" + recept.hashCode());

        return Response
            .ok(recept)
            .tag(eTag )
            .cacheControl(cacheControl)
            .build();
    }
}

PlayJavaReceptResource.java

package controllers;

import play.mvc.*;
import test.ReceptRepository;

import static play.libs.Json.toJson;
import static test.ReceptRepository.*;

public class PlayJavaReceptResource extends Controller {

    public static Result all() {
        return ok( toJson( ReceptRepository.all() ) );
    }
    
    public static Result get(int id) {
        Recept recept = ReceptRepository.get(id);
        if(recept == null){
            return notFound("Recept " +id +" finns inte");
        }
        response().setHeader(CACHE_CONTROL, "max-age=3600");
        response().setHeader(ETAG, "" +recept.hashCode());
        return ok( toJson(recept) );
    }
}

PlayResource.scala

package controllers

import play.api.mvc._
import com.codahale.jerkson.Json._
import test.ReceptRepository
import play.api.http.ContentTypes

object ReceptResource extends Controller {

  def get(id: Int) = Action { request =>
    ReceptRepository.get(id) match {
      case Some(recept) =>
        Ok( generate(recept))
          .withHeaders(
            CACHE_CONTROL -> "max-age=3600",
            ETAG -> ("" + recept.hashCode()))
          .as(ContentTypes.JSON)
      case none => NotFound
    }
  }
  
  def all = Action {
    Ok( generate( ReceptRepository.all)).as(ContentTypes.JSON)
  }
}

ReceptRepository.java

package test;

import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlRootElement;
import java.util.*;

public class ReceptRepository {
    private static Map<Integer, Recept> data = new HashMap<Integer, Recept>();
    static {
        List<ReceptIngrediens> sjomansbiffIngredienser =new ArrayList<ReceptIngrediens>();
        sjomansbiffIngredienser.add(new ReceptIngrediens(1, "Sjöman"));
        sjomansbiffIngredienser.add(new ReceptIngrediens(1, "Öl"));
        Recept sjomansbiff = new Recept(1, "Sjömansbiff", "Koka den hackade sjömannen i länge i öl", sjomansbiffIngredienser);

        List<ReceptIngrediens> fiskMedSasIngredienser =new ArrayList<ReceptIngrediens>();
        fiskMedSasIngredienser.add(new ReceptIngrediens(1, "Fisk"));
        fiskMedSasIngredienser.add(new ReceptIngrediens(1, "Sås"));
        Recept fiskMedSas = new Recept(2, "Fisk med Sås", "Blanda fisken med såsen", fiskMedSasIngredienser);

        data.put(sjomansbiff.id, sjomansbiff);
        data.put(fiskMedSas.id, fiskMedSas);
    }

    public static Collection<Recept> all() {
        return data.values();
    }

    public static Recept get(int id) {
        return data.get(id);
    }

    @XmlRootElement
    @XmlAccessorType(XmlAccessType.FIELD)
    static public class Recept {
        public final int id;
        public final String namn;
        public final String beskrivning;
        public final List<ReceptIngrediens> ingrediensLista;

        /* Jaxb need this default constructor */
        private Recept(){
            id = 0;
            namn = null;
            beskrivning = null;
            ingrediensLista = null;
        }
        public Recept(int id, String namn, String beskrivning, List<ReceptIngrediens> ingredienser){
            this.id = id;
            this.namn = namn;
            this.beskrivning = beskrivning;
            this.ingrediensLista = ingredienser;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (!(o instanceof Recept)) return false;

            Recept recept = (Recept) o;

            if (id != recept.id) return false;
            if (beskrivning != null ? !beskrivning.equals(recept.beskrivning) : recept.beskrivning != null)
                return false;
            if (ingrediensLista != null ? !ingrediensLista.equals(recept.ingrediensLista) : recept.ingrediensLista != null)
                return false;
            if (namn != null ? !namn.equals(recept.namn) : recept.namn != null) return false;

            return true;
        }

        @Override
        public int hashCode() {
            int result = id;
            result = 31 * result + (namn != null ? namn.hashCode() : 0);
            result = 31 * result + (beskrivning != null ? beskrivning.hashCode() : 0);
            result = 31 * result + (ingrediensLista != null ? ingrediensLista.hashCode() : 0);
            return result;
        }
    }

    @XmlRootElement
    @XmlAccessorType(XmlAccessType.FIELD)
    static public class ReceptIngrediens {
        public final int mangd;
        public final String beskrivning;

        /* Jaxb need this default constructor */
        private ReceptIngrediens(){
            mangd = 0;
            beskrivning = null;
        }
        public ReceptIngrediens(int mangd, String beskrivning){
            this.mangd = mangd;
            this.beskrivning = beskrivning;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (!(o instanceof ReceptIngrediens)) return false;

            ReceptIngrediens that = (ReceptIngrediens) o;

            if (mangd != that.mangd) return false;
            if (beskrivning != null ? !beskrivning.equals(that.beskrivning) : that.beskrivning != null) return false;

            return true;
        }

        @Override
        public int hashCode() {
            int result = mangd;
            result = 31 * result + (beskrivning != null ? beskrivning.hashCode() : 0);
            return result;
        }
    }
}

ReceptRepository.scala

package test

case class Recept(id: Int, namn: String, beskrivning: String, ingredienser: List[ReceptIngrediens])
case class ReceptIngrediens(mangd: Int, namn: String)

object ReceptRepository {
  val sjomansBiff = Recept(1,
                           "Sjömansbiff",
                           "Hacka en sjöman. Lägg i en gryta. Koka i öl. Länge.",
                           List( ReceptIngrediens(1, "Sjöman"),
                                 ReceptIngrediens(1, "Öl")))
  val fiskMedSas = Recept(2,
                          "Fisk med sås",
                          "Ta en fisk. Blanda med sås",
                          List( ReceptIngrediens(1, "Fisk"),
                                ReceptIngrediens(1, "Sås")))

  val data: Map[Int, Recept] = Map(sjomansBiff.id -> sjomansBiff, fiskMedSas.id -> fiskMedSas)

  def get(id: Int): Option[Recept] = data.get(id)
  def all: Iterable[Recept] = data.values
}

routes

GET     /recept                         controllers.ReceptResource.all
GET     /recept/:id                     controllers.ReceptResource.get(id: Int)

Nice...