comparing groovy & jruby *

Transcription

1 ThoughtWorks comparing groovy & jruby * * please check all knives, guns, pitchforks, and torches at the door NEAL FORD software architect / meme wrangler ThoughtWorks nford@thoughtworks.com 3003 Summit Boulevard, Atlanta, GA blog: memeagora.blogspot.com twitter: neal4d

2 housekeeping ask questions at the end (insane amount of material!) download slides from nealford.com download samples from github.com/nealford

3 agenda: syntax closures eigenclass approaches meta-programming framework approach

4 geek fu test:

5 Groovy dynamicizes the Java TM platform JRuby brings Ruby to the Java TM platform

6 strong dynamic static weak

7

8 differences & observations

9 syntax

10 sigils

11 this.name

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14 auto-encapsulation?

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16

17 Perl!!!!!!!!!

18 Ruby has some Perl-isms......with significant differences

19 closures

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24 passing closures

25 auto-blocks

26 passing closures

27 everything except... in Java, everything is an object......except primitives and nulls in Groovy, everything is an object... except null in JRuby, everything is an object

28 null is null?. handles protected reference person?.address?.street

29 nil is an instance of NilClass

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31 switch/case statement

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34 === iscase()

35 spread operator

36 elvis operator

37 side effects of encapsulating Java

38 things added to Object

39 supporting collections

40 really? really!

41 JRuby additions JRuby adds artifacts to Rubify Java ArrayList...but doesn t add collection stuff to Object Fixnum

42 Groovy is optionally typed

43

44 search exists on Stack but not on ArrayList or List!

45 interfaces & mixins

46 Groovy & interfaces allows you to interact with Java interfaces can wrap proxies around them if needed fake out interfaces via closures using as

47

48 be careful when implementing with a map: NullPointerException if you forget a method

49 Ruby has no interfaces mixin first appeared in symbolic logic s flavors system named after ice cream mix-ins not a form of specialization a way to collect functionality

50

51 comparisons

52 comparisons

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55 comparisons

56 violating handshakes

57 mixins in Groovy, interfaces in JRuby

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59 interfaces in JRuby?

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61 meta-programming

62 mostly parity (functionally) very different implementations

63 executable declarations much of Ruby s infrastructure is metaprogramming meta-programming methods: attr_reader, attr_writer, attr_accessor include private, protected, public

64 AST transformations

65 implementation

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67 optional inclusion

68 conditional method

69 attributes

70 hook methods

71 sticky attributes private, protected, public

72 eigenclass

73 adding methods via proxies

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75 Groovy s eigenclass

76 framework approach

77 encapsulate & extend

78 Groovy & Grails leverage the existing industrial strength Java stack encapsulate best-of-breed frameworks use Groovy to simplify and humanize them encapsulate, then build up

79

80 abstraction layers via meta dsl

81 Ruby tends to build things as abstraction layers atop Ruby using meta-programming & dsl techniques Ruby on Rails = software factories + dsl s Ruby language is always 1 abstraction layer down lightweight abstraction layers

82 case study: builders

83 GroovyObjectSupport BuilderSupport MarkupBuilder

84

85 builder

86 builder works via method_missing but what about this?

87

88 the problem: how do you inherit from object......with inheriting from object?

89 1.8 Jim Weirich s BlankSlate Object BasicObject BlankSlate Recorder Builder Recorder Builder 1.9 BasicObject

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91 different philosophies Groovy encapsulates and builds up Ruby either builds abstractions with dsl s via meta-programming

92 summary

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95 the good unparalleled Java integration willing to evolve the language the real JDK 2.0! building up from best-of-breed

96 the bad fast changing at the core single runtime platform never spread out of the Java community framework approach?

97 def name public String getname() public void setname(string name)

98

99 the good well established (older than Java ) virtually effortless meta-programming futuristic framework approach truly cross platform, for the new definition of platform interpreted, then jit-ted

100 the bad some impedance mismatch with Java (smaller all the time) yet another language to learn unfamiliar frameworks you have to switch to a new community you have to learn to think like a Ruby-ist

101

102 ThoughtWorks? s please fill out the session evaluations samples at github.com/nealford NEAL FORD software architect / meme wrangler ThoughtWorks This work is licensed under the Creative Commons Attribution-Share Alike 3.0 License. nford@thoughtworks.com 3003 Summit Boulevard, Atlanta, GA blog: memeagora.blogspot.com twitter: neal4d

103 ThoughtWorks resources Cow in the Road photo by Sophia Huda, from Flickr, under a Creative Commons license groovy web site jruby site ola bini s blog charles nutter s blog

104 ThoughtWorks resources jeff brown s blog graeme rocher s blog aboutgroovy venkat subramaniam s blog