The document introduces the Play Framework version 2.1 and highlights its key features. It demonstrates building a sample application in Scala using Play's reactive, non-blocking architecture. Key features discussed include Play's built-in support for Scala, reactive programming, JSON APIs, routing, templates, and testing.

1. PLAY FRAMEWORK
Introduction & highlights of v2.1

2. WHO AM I?
Andrew Skiba
I work in Tikal as the leader of
Java group.
With over 50 Java experts, we
meet, share, contribute, and
code together on a monthly
basis.

3. YES! WE START A NEW PROJECT!

4. NEW PROJECT DILEMMA

5. WITH RISK OF ENDING UP WITH POLYGLOT PROJECT WITH
MIX OF LANGUAGES AND TECHNOLOGIES - OR EVEN
REWRITING PARTS OF YOUR APPLICATION LATER...

6. WHAT HAPPENED, TWITTER?
• Bill Venners: I’m curious, and the Ruby folks will want it spelled
out: Can you elaborate on what you felt the Ruby language lacked in
the area of reliable, high performance code?
• Steve Jenson: One of the things that I’ve found throughout my
career is the need to have long-lived processes. And Ruby, like many
scripting languages, has trouble being an environment for long lived
processes. But the JVM is very good at that, because it’s been
optimized for that over the last ten years.

7. JAVA IS A SAFE CHOICE
Except the risk of dying while waiting for builds & redeployments, or
maintaining XML configurations...

8. CAN YOU HAVE YOUR CAKE AND
EAT IT, TOO?

9. PLAY FRAMEWORK
Combine them all!

10. STRONG & FAST
Fast turnaround - just save and refresh browser

11. Text
REACTIVE
Event driven non blocking IO

12. SCALABLE
Stateless, non blocking, web-friendly architecture

13. COMPLETE
Easy things are easy, complicated things are possible

14. DEMO OF А NEW PROJECT

15. IT LOOKS LIKE A MAGIC!

16. SO JAVA OR SCALA?

17. FUNCTIONAL/OO BLEND

18. val qsort: List[Int] => List[Int] = {
case Nil => Nil
case pivot :: tail =>
val (smaller, rest) = tail.partition(_ < pivot)
qsort(smaller) ::: pivot :: qsort(rest)
}
EXPRESSIVENESS

19. JAVA COMPATIBILITY

20. UNPRECEDENTED TYPE SAFETY

21. DSLS

22. COMMUNITY

23. 'NOUGH SAID!
• Charles Nutter, creator of JRuby: "Scala, it must be stated, is the
current heir apparent to the Java throne. No other language on the
JVM seems as capable of being a "replacement for Java" as Scala, and
the momentum behind Scala is now unquestionable."
• James Strachan, creator of Groovy: "I can honestly say if
someone had shown me the Programming in Scala book by by
Martin Odersky, Lex Spoon & Bill Venners back in 2003 I'd
probably have never created Groovy."

24. def index = Action {
import play.api.libs.json._
val json = Json.obj(
"status" -> "OK",
"message" -> "Hello",
"framework" -> Json.obj(
"name" -> "Play"))
val jsonTransformer = (
__ 'framework).json.update(
__.read[JsObject].map { o => o ++ Json.obj("version" -> "2.1.0") })
Ok(
json.transform(jsonTransformer).get
)
}
DEMO OF SCALA POWER
New JSON API with REPL

25. ORDER OF THINGS

26. app → Application sources
└ assets → Compiled asset sources
└ stylesheets → Typically LESS CSS sources
└ javascripts → Typically CoffeeScript sources
└ controllers → Application controllers
└ models → Application business layer
└ views → Templates
conf → Configurationurations files and other non-compiled
resources
└ application.conf → Main configuration file
└ routes → Routes definition
public → Public assets
└ stylesheets → CSS files
└ javascripts → Javascript files
└ images → Image files
project → sbt configuration files
└ build.properties → Marker for sbt project
└ Build.scala → Application build script
└ plugins.sbt → sbt plugins
ANATOMY OF A PLAY APPLICATION

27. # The home page
GET / controllers.Projects.index
# Authentication
GET /login controllers.Application.login
POST /login controllers.Application.authenticate
GET /logout controllers.Application.logout
# ...
# Tasks
GET /projects/:project/tasks controllers.Tasks.index(project: Long)
POST /projects/:project/tasks controllers.Tasks.add(project: Long, folder: String)
PUT /tasks/:task controllers.Tasks.update(task: Long)
DELETE /tasks/:task controllers.Tasks.delete(task: Long)
# ...
# Javascript routing
GET /assets/javascripts/routes controllers.Application.javascriptRoutes
# Map static resources from the /public folder to the /assets path
GET /assets/*file controllers.Assets.at(path="/public", file)
POWERFUL URL ROUTING

28. POWERFUL TEMPLATE ENGINE

29. UNIFIED ERROR REPORTING

30. TASTING MENU

31. @org.springframework.stereotype.Service
public class HelloService {
public String hello() {
return "Hello world!";
}
}
//////////////////
@org.springframework.stereotype.Controller
public class Application extends Controller {
@Autowired
private HelloService helloService;
public Result index() {
return ok(index.render(helloService.hello()));
}
}
SPRING WITH PLAY

32. DEMO OF REQUIREJS

33. TESTING
including a browser simulator!

34. in main project
# The home page
GET / controllers.Application.index
# Include a sub-project
-> /my-subproject my.subproject.Routes
in conf/my.subproject.routes
GET / my.subproject.controllers.Application.index
now just surf to /my-subproject and get called
my.subproject.controllers.Application.index
DEMO OF SUBROUTES

35. val query = BSONDocument("firstName" -> BSONString("Jack"))
// get a Cursor[DefaultBSONIterator]
val cursor = collection.find(query)
// let's enumerate this cursor and print a readable
// representation of each document in the response
cursor.enumerate.apply(Iteratee.foreach { doc =>
println("found document: " + BSONDocument.pretty(doc))
})
// or, the same with getting a list
val cursor2 = collection.find(query)
val futurelist = cursor2.toList
futurelist.onSuccess {
case list =>
val names = list.map(_.getAs[BSONString]("lastName").get.value)
println("got names: " + names)
}
DEMO OF REACTIVE MONGO

37. LINKS
• http://www.playframework.com/ (Doh!)
• http://typesafe.com/stack
• http://blog.typesafe.com/scala-akka-and-play-framework-at-devoxx-2012
• http://typesafe.com/public/case-studies/LinkedInCase_v8.pdf
• http://docs.cloudfoundry.com/frameworks/play/java-mongodb.html
• https://github.com/wsargent/play-2.0-spring-module
• http://jonasboner.com/2008/10/06/real-world-scala-dependency-injection-di/