Javaslang DevoxxBE 2016

Transcript

1. @pivovarit
   #Devoxx #javaslang
   Grzegorz Piwowarek
   

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2. @pivovarit
   #Devoxx #javaslang
   /dev/pivovarit
   Dev@TouK
   Senior Editor@Baeldung
   Yoyo Player
   Musician
   

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3. @pivovarit
   #Devoxx #javaslang
   Functional Java 8
   

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4. @pivovarit
   #Devoxx #javaslang
   Functional Java 8
   

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5. @pivovarit
   #Devoxx #javaslang
   Functional Java 8
   

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6. @pivovarit
   #Devoxx #javaslang
   Issues
   ● Only 3 functional control structures
   ● No memoization
   ● No partial functions lifting
   ● No tuples
   ● Optional extends NOT Serializable/Iterable
   ● Lack of Stream/Optional in APIs
   ● “Type pollution”
   ● list.stream().map(...).collect(Collectors.toList())
   ● ...
   

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7. @pivovarit
   #Devoxx #javaslang
   ● Declared params
   ● Mutable instance state
   ● Mutable global state
   ● Declared return value
   ● Mutable instance state
   ● Mutable global state
   ● Mutable params
   ● Exceptions
   Potential inputs
   Potential outputs
   

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8. @pivovarit
   #Devoxx #javaslang
   ● Declared params
   ● Mutable instance state
   ● Mutable global state
   ● Declared return value
   ● Mutable instance state
   ● Mutable global state
   ● Mutable params
   ● Exceptions
   Potential inputs
   Potential outputs
   

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9. @pivovarit
   #Devoxx #javaslang
   ● Declared params
   ● Mutable instance state
   ● Mutable global state
   ● Declared return value
   ● Mutable instance state
   ● Mutable global state
   ● Mutable params
   ● Exceptions
   Potential inputs
   Potential outputs
   

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10. @pivovarit
    #Devoxx #javaslang
    Functional programming
    is not about lambdas.
    

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11. @pivovarit
    #Devoxx #javaslang
    Functional programming is about writing pure functions, about
    removing hidden inputs and outputs as far as we can, so that
    as much of our code as possible just describes a relationship
    between inputs and outputs.
    http://blog.jenkster.com/2015/12/what-is-functional-programming.html
    

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12. @pivovarit
    #Devoxx #javaslang
    Immutability
    Referential Transparency
    

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13. @pivovarit
    #Devoxx #javaslang
    

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14. @pivovarit
    #Devoxx #javaslang
    

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15. @pivovarit
    #Devoxx #javaslang
    

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16. @pivovarit
    #Devoxx #javaslang
    Collections API:
    ● boolean add()
    ● boolean remove()
    ● void clear()
    ● ...
    

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17. @pivovarit
    #Devoxx #javaslang
    

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18. @pivovarit
    #Devoxx #javaslang
    

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19. @pivovarit
    #Devoxx #javaslang
    λ
    Tuple
    Value
    

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20. @pivovarit
    #Devoxx #javaslang
    

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21. @pivovarit
    #Devoxx #javaslang
    

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22. @pivovarit
    #Devoxx #javaslang
    

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23. @pivovarit
    #Devoxx #javaslang
    

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24. @pivovarit
    #Devoxx #javaslang
    

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25. @pivovarit
    #Devoxx #javaslang
    

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26. @pivovarit
    #Devoxx #javaslang
    

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27. @pivovarit
    #Devoxx #javaslang
    

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28. @pivovarit
    #Devoxx #javaslang
    

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29. @pivovarit
    #Devoxx #javaslang
    

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30. @pivovarit
    #Devoxx #javaslang
    

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31. @pivovarit
    #Devoxx #javaslang
    

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32. @pivovarit
    #Devoxx #javaslang
    

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33. @pivovarit
    #Devoxx #javaslang
    

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34. @pivovarit
    #Devoxx #javaslang
    

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35. @pivovarit
    #Devoxx #javaslang
    

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36. @pivovarit
    #Devoxx #javaslang
    

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37. @pivovarit
    #Devoxx #javaslang
    Pattern Matching
    

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38. @pivovarit
    #Devoxx #javaslang
    

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39. @pivovarit
    #Devoxx #javaslang
    

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40. @pivovarit
    #Devoxx #javaslang
    

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41. @pivovarit
    #Devoxx #javaslang
    

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42. @pivovarit
    #Devoxx #javaslang
    

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43. @pivovarit
    #Devoxx #javaslang
    

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44. @pivovarit
    #Devoxx #javaslang
    

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45. @pivovarit
    #Devoxx #javaslang
    Thank You!
    Psssst, I have stickers.
    

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