TechEmpower.FrameworkBenchmarks/play-java/app/controllers/Application.java

package controllers;

import models.World;
import play.libs.F;
import play.libs.Json;
import static play.libs.Akka.future;
import org.codehaus.jackson.node.ObjectNode;
import org.codehaus.jackson.map.ObjectMapper;
import play.mvc.Controller;
import play.mvc.Result;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.concurrent.Callable;
import java.util.concurrent.ThreadLocalRandom;

public class Application extends Controller {

    private static final int TEST_DATABASE_ROWS = 10000;
    //http://stackoverflow.com/questions/3907929/should-i-make-jacksons-objectmapper-as-static-final
    private static final ObjectMapper objectMapper = new ObjectMapper();

    public static Result json() {
        final ObjectNode result = objectMapper.createObjectNode();
        result.put("message", "Hello World!");
        return ok(result);
    }

    public static Result db(final Integer queries) {
        return async(
          future(new Callable<Result>() {
              @Override
              public Result call() {
                  final Random random = ThreadLocalRandom.current();
                  final List<F.Promise<? extends World>> promises = new ArrayList<F.Promise<? extends World>>(queries);
                  for (int i = 0; i < queries; ++i) {
                      promises.add(future(findWorld(Long.valueOf(random.nextInt(TEST_DATABASE_ROWS) + 1))));
                  }
                  final List<World> worlds = F.Promise.sequence(promises).get();
                  return ok(Json.toJson(worlds));
              }

              private Callable<World> findWorld(final Long id) {
                  return new Callable<World>() {
                      @Override
                      public World call() {
                          return World.find.byId(id);
                      }
                  };
              }
          })
        );

    }
}