- Scala is an object-oriented and functional programming language that runs on the Java Virtual Machine (JVM) and is interoperable with Java code - Scala aims to improve on statically typed languages by better supporting reusable components through unifying functional programming and object-oriented programming concepts - This is achieved through representing functions as objects, encoding algebraic data types as classes, and modeling components as objects that can be composed through mixins

1. Scala a successor to java CWI team

3. Scala a successor to java

8. www.exoplatform.com Copyright 2011 eXo Platform 1 st Unification ADTs are class hierarchies Many functional languages have algebraic data types and pattern matching =>Concise and canonical manipulation of data structure From object-oriented point of view -”ADTs are not extensible” - “ADTs violate the purity of the OO data model” - “Pattern matching breaks encapsulation” => using class hierarchies.

9. www.exoplatform.com Copyright 2011 eXo Platform 1 st Unification ADTs are class hierarchies With class hierarchies contents is encapsulaated in the object and accessed through methods With ADTs : data is accessed through decomposing the value by pattern matching ADTs and class hierarchies have complementary strength and weakness - ADTs allow easy extension of operations supported by the data - While class hierarchies allow easy addition of data variants

10. www.exoplatform.com Copyright 2011 eXo Platform 1 st Unification ADTs are class hierarchies ADTs can be encoded using case classes - Case classes are like normal classes. - Instance constructors can be recovered by pattern matching - Structural equality is used for comparison - The new keyword is optional for instance creation. Case class ClockTime(hour: Int, min:Int) is a valid case class definition. ClockTime(10,30) creates an instance

23. Q & A

24. Thank you!