A fast intro to Scala and Play, to prepare the audience for a live demo of a Play Application using Futures to get weather data from Yahoo in a non blocking way, then display to the user the results. The code is available here https://github.com/tabdulradi/weather

1. Play-ing with Scala Futures
Backend guy at Cloud9rs Ltd.
(aka Senior Software Engineer)
tabdulradi@cloud9ers.com
twitter.com/tamer_radi
(few tweets, if any!)

2. About Scala
Martin Odersky
● He designed Java Generics
● Built the javac compiler
● In 2001, designed Scala
● In 2011, he founded
Typesafe Inc., a company
to support and promote
Scala

3. Who Uses Scala
More: http://www.scala-lang.org/node/1658

4. Why Scala
Can borrow from Java (runs on JVM)
Concise
Very OOP, Very Functional
Statically type, but with type inference.
Lazy values
class Rectangle(val w: Int, val l: Int)
class Square(s: Int) extends Rectangle(s, s)

5. Why Scala - Traits
Traits for cross-cutting modularity
Like Interfaces, but with implementation
class Man { def walk() {....} }
trait SuperPowers { def fly() {....} }
class SuperMan extends Man with SuperPowers
val superMan = new SuperMan
val superMan = new Man with SuperPowers
object SuperMan extends Man with SuperPowers {
def doLaserAndStuff() { ... } }

6. Why Scala - Concurrency
Parallel Collections
(1 to 10000).par.map(_ * 2).reduce(_ + _)
Note: reduce operation is not ordered
Futures
future { slowOperation() } foreach println
println("Hey, I don't have to wait")
Akka Actors (http://akka.io)

7. Play Framework
Stateless (easy to scale)
Built on Akka
Non-blocking I/O (uses JBoss Netty)
Real-time & Streaming are First Class Citizins
Websockets
EventSource
Comet
Production support by Typesafe
Many cloud deployment options

8. Now Let's Code..
The code is available on
https://github.com/tabdulradi/weather