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@@ -1,81 +0,0 @@
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-package controllers;
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-
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-import akka.dispatch.ExecutionContexts;
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-import com.fasterxml.jackson.databind.ObjectMapper;
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-import com.fasterxml.jackson.databind.node.ObjectNode;
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-import models.World;
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-import play.Play;
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-import play.core.NamedThreadFactory;
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-import play.libs.F;
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-import play.libs.Json;
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-
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-import play.mvc.Controller;
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-import play.mvc.Result;
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-import scala.concurrent.ExecutionContext;
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-import utils.Predicate;
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-import utils.Predicated;
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-
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-import java.util.ArrayList;
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-import java.util.List;
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-import java.util.Random;
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-import java.util.concurrent.*;
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-
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-public class Application extends Controller {
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-
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- private static final int MAX_QUERIES_PER_REQUEST = 20;
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- private static final int TEST_DATABASE_ROWS = 10000;
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- //http://stackoverflow.com/questions/3907929/should-i-make-jacksons-objectmapper-as-static-final
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- private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();
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-
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- private static final int partitionCount = Play.application().configuration().getInt("db.default.partitionCount");
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- private static final int maxConnections =
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- partitionCount * Play.application().configuration().getInt("db.default.maxConnectionsPerPartition");
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- private static final int minConnections =
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- partitionCount * Play.application().configuration().getInt("db.default.minConnectionsPerPartition");
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-
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- private static final ThreadPoolExecutor tpe = new ThreadPoolExecutor(minConnections, maxConnections,
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- 0L, TimeUnit.MILLISECONDS,
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- new LinkedBlockingQueue<Runnable>(),
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- new NamedThreadFactory("dbEc"));
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- private static final ExecutionContext dbEc = ExecutionContexts.fromExecutorService(tpe);
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-
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- // A predicate for checking our ability to service database requests is determined by ensuring that the request
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- // queue doesn't fill up beyond a certain threshold. For convenience we use the max number of connections * the max
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- // # of db requests per web request to determine this threshold. It is a rough check as we don't know how many
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- // queries we're going to make or what other threads are running in parallel etc. Nevertheless, the check is
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- // adequate in order to throttle the acceptance of requests to the size of the pool.
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- public static class IsDbAvailable implements Predicate {
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- @Override
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- public boolean condition() {
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- return tpe.getQueue().size() < maxConnections * MAX_QUERIES_PER_REQUEST;
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- }
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- }
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-
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- public static Result json() {
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- final ObjectNode result = OBJECT_MAPPER.createObjectNode();
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- result.put("message", "Hello, World!");
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- return ok(result);
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- }
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-
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- @Predicated(predicate = IsDbAvailable.class, failed = SERVICE_UNAVAILABLE)
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- public static F.Promise<Result> db(final Integer queries) {
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- final Random random = ThreadLocalRandom.current();
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- final List<F.Promise<? extends World>> promises = new ArrayList<F.Promise<? extends World>>(queries);
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- for (int i = 0; i < queries; ++i) {
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- final F.Promise<World> p = F.Promise.promise(new F.Function0<World>() {
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- @Override
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- public World apply() throws Throwable {
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- return World.find.byId(Long.valueOf(random.nextInt(TEST_DATABASE_ROWS) + 1));
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- }
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- }, dbEc);
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- promises.add(p);
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- }
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- return F.Promise.sequence(promises).map(new F.Function<List<World>, Result>() {
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- @Override
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- public Result apply(List<World> worlds) {
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- return ok(Json.toJson(worlds));
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- }
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- });
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- }
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-
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-}
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