Play! Framework ile Asenkron HTTP

Application.java

public class Application extends Controller {

    public static void index() throws Throwable {

        Either<User, Throwable> result = await(Client.createUser("testuser", 
                                                                 "Foo", 
                                                                 "Bar"));
        if (result._1.isDefined()) {
            result = await(Client.getUser("testuser"));
            if (result._1.isDefined()) {
                final User created = result._1.get();
                Logger.info("Kullanıcı oluşturuldu: name:%s surname:%s", 
                            created.name, 
                            created.surname);
            } else {
                throw result._2.get();
            }
        } else {
            throw result._2.get();
        }
        render();
    }
}

Client.java

public class Client {

    public static final String BASE_URL = "http://localhost:9001";

    public static Promise<Either<User, Throwable>> getUser(final String username) {

        final Map<String, String> params = new HashMap<String, String>();
        params.put("username", username);
        return new ClientJob<User>(HttpMethod.GET, 
                                   BASE_URL + "/api/user", 
                                   params, 
                                   User.class).now();
    }

    public static Promise<Either<User, Throwable>> createUser(final String username, 
                                                              final String name,
                                                              final String surname) {

        final Map<String, String> params = new HashMap<String, String>();
        params.put("username", username);
        params.put("name", name);
        params.put("surname", surname);
        return new ClientJob<User>(HttpMethod.POST, 
                                   BASE_URL + "/api/user", 
                                   params, 
                                   User.class).now();
    }
}

ClientJob.java

public final class ClientJob<V> extends Job<Either<V, Throwable>> {

    private final HttpMethod method;

    private final String url;

    private final Map<String, String> params;

    private final Class<V> clazz;

    public ClientJob(final HttpMethod method, 
                     final String url, 
                     final Map<String, String> params, 
                     final Class<V> clazz) {

        this.method = method;
        this.url = url;
        this.params = params;
        this.clazz = clazz;
    }

    @Override
    public Either<V, Throwable> doJobWithResult() throws Exception {

        try {
            final String json = doRequest(this.method, this.url, this.params);
            Logger.debug(json);
            final V result = new Gson().fromJson(json, this.clazz);
            return Either._1(result);
        } catch (final Throwable throwable) {
            return Either._2(throwable);
        }
    }

    private static String doRequest(final HttpMethod method, 
                                    final String url, 
                                    final Map<String, String> params) {

        final WSRequest wsRequest = WS.url(url).setParameters(params);

        final HttpResponse response;
        switch (method) {
        case HEAD:
            response = wsRequest.head();
            break;
        case GET:
            response = wsRequest.get();
            break;
        case PUT:
            response = wsRequest.put();
            break;
        case POST:
            response = wsRequest.post();
            break;
        case DELETE:
            response = wsRequest.delete();
            break;
        default:
            response = null;
        }

        switch (response.getStatus()) {
        case 200:
            return response.getString();
        default:
            throw new UnexpectedException(response.getString());
        }
    }
}

HttpMethod.java

public enum HttpMethod {
    HEAD, 
    GET, 
    PUT, 
    POST, 
    DELETE
}

Provider.java

public class Provider extends Controller {

    public static void getUser(final String username) {
        final User user = User.find("byUsername", username).first();
        renderJSON(user);
    }

    public static void createUser(final String username, 
                                  final String name, 
                                  final String surname) {
        final User user = new User(username, name, surname).save();
        renderJSON(user);
    }
}

User.java

@Entity
public class User extends Model {

    @Column(unique = true, nullable = false)
    public String username;

    public String name;

    public String surname;

    public User(final String username, 
                final String name, 
                final String surname) {
        this.username = username;
        this.name = name;
        this.surname = surname;
    }
}