A Glimpse of a Scala - Java Meetup Novi Sad May 2014

I gave an introduction to Scala at Novi Sad on 29.05.2014. The corresponding code examples can be found here: https://github.com/lukaspustina/A-Glimpse-Of-Scala-Java-Meet-Up-in-Novi-Sad

Transcript

1. A Glimpse of Scala
   Dr. Lukas Pustina
   @drivebytesting
   codecentric AG
   

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2. Which Programming Language
   would you use now on top of
   JVM? Scala!
   James Gosling, Father of Java
   

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3. Scala is fun
   and designed for the future.
   

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4. @drivebytesting
   

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5. What to expect
   

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6. Syntax vs. Idioms
   How to use a language.
   

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7. Before we start
   

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8. Open your mind
   

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9. Let’s program our minds
   The brain has bugs
   

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10. Exposure Effect
    We prefer things we know and are familiar with
    

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12. “Gott würfelt nicht!”
    “God doesn’t role the dice!” — Albert Einstein
    

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13. Bundesarchiv, Bild183-R57262 / CC-BY-SA
    

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14. Today’s
    Challenges
    

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15. CPU Memory
    

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16. !Von Neumann
    Bottleneck
    

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17. Can Programming Be
    Liberated from the von
    Neumann Style
    A Functional Style and Its Algebra of Programs —
    John Backus, 1977
    

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18. CPU Memory
    Cache
    

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19. CPU Memory
    Cache Cache
    

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20. CPU Memory
    Cache Cache
    Core
    Core
    Core
    Core
    

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21. CPU Memory
    Cache Cache
    Core
    Core
    Core
    Core
    

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22. !False Sharing
    

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23. Cache
    Cache
    Cache
    Core
    Core
    

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24. Cache
    Cache
    Cache
    Core
    Core
    

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25. Cache
    Cache
    Cache
    Core
    Core
    

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26. !I/O Waits
    

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27. This is the future
    Massive parallel computing
    

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28. ?Threads
    The software engineers’ answer
    

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29. A Universal
    Modular Actor Formalism for
    Artificial Intelligence
    Carl Hewitt, Peter Bishop, Richard Steiger 1973
    

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30. Reactive Programming
    Immutability, Functional, Actors are one approach.
    

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31. A Glimpse of
    Scala
    

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32. SCAlable LAnguage
    A multi-paradigm language
    

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33. Return of
    Computer Science
    Bear with me :)
    

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34. Object oriented,
    functional language
    Multi-paradigm language
    

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35. OO and func
    • State Mutation vs. Immutability
    • Object Composition vs. Functional Composition
    • Class Hierarchies vs. Pattern Matching
    

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36. Type Inference
    The type of variables and functions is interfered from
    assignments and return values.
    

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37. Immutability
    Immutability right in the language: val and immutable
    collections.
    

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38. Functions as
    1st class citizens
    Pass a function as you would pass an Int, a String, or
    an arbitrary object.
    

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39. Hello World
    The first program in the REPL
    

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40. [lukas@muffin] ~ ➜ scala!
    Welcome to Scala version 2.11.1 (Java HotSpot(TM) 64-Bit Server VM,
    Java 1.7.0_51).!
    Type in expressions to have them evaluated.!
    Type :help for more information.!
    !
    scala> print("Hello World")!
    Hello World
    

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41. A Closer Look
    

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42. With great power …
    … comes great responsibility.
    

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43. @drivebytesting
    

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44. End
    Dr. Lukas Pustina
    @drivebytesting
    codecentric AG
    

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