Scala

Core Concepts & Features

Immutable
Functions as 1. class citizens
Object Oriented & Functional
Concurrent by Design
Less Boilerplate Code
JVM Language

Start Small

Scala vs. Java

Syntax Comparison

Variables

Java - mutable by default

String foo = "foo";

final String foo = "foo";

Scala - Immutable by default

val foo = "foo"

var foo = "foo"

Functions

Java

public String foo() {   return "foo";}

Scala - less is more (readable)

def foo(): String = {
   "foo"}def foo(): String = "foo"def foo() = "foo"def foo = "foo"

Classes

Java

public class Foo {    private final String bar;   public Foo() {      this("empty");   }   public Foo(String bar) {      this.bar = bar;   }   public String getBar() {      return bar;   }}

Scala - less is more (readable)

class Foo(bar: String = "empty")

Traits vs. Interfaces

Java (7)

interface Foo {   public void bar();}

Scala

trait Foo {   def bar()}

object vs static

Java - static keyword

class Foo() {   public String static bar() {      return "bar";   }}

Scala - object keyword

object Foo {   def bar() = "bar"}

SBT

Maven für Scala
Interaktiv
Jeder startet als Hater

build.sbt

name := "tdd-katas"

version := "1.0-SNAPSHOT"

scalaVersion := "2.10.4"

global Plugins

~/.sbt/0.13/plugins/plugins.sbt

addSbtPlugin("com.typesafe.sbteclipse" % "sbteclipse-plugin" % "2.2.0")
addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.6.0")

~/.sbt/0.13/global.sbt

resolvers += "Typesafe repository" at "http://repo.typesafe.com/typesafe/releases/"

resolvers += "IA Nexus" at "http://buildsystem-ana.rz1.intelliad.com:8081/nexus/content/groups/public/"

Links & Readmes

K a t a

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