A Groovy journey in Open Source land

In dog years... err... Open Source years, the Groovy programming language project is a very mature and successful one, as its 12+ million downloads a year can attest. The Groovy language is certainly the most widely deployed alternative language of the JVM today. But how do we go from a hobby night & week-end project to professionally company sponsored? And back again to hobby mode but joining the wider Apache Software Foundation community?

Guillaume will guide you through the history of the project, its latest developments, and its recent news, outlining the importance of a community around an Open Source project.

Also, we'll discuss what it means to contribute, when it's your hobby or as a paid committer -- what does it change? What it means to join the Apache community, what the impact of professional Open Source is, and more.

Transcript

1. A Groovy Journey in
   Open Source Land
   Guillaume Laforge / @glaforge
   Chair of the Apache Groovy PMC
   

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2. A Groovy Journey in
   Open Source Land
   Guillaume Laforge / @glaforge
   Chair of the Apache Groovy PMC
   

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4. GR8Conf Promo Code: ctwgr8conftw
   http://www.manning.com/koenig2/
   GROOVY
   IN ACTION
   2ND EDITION
   

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5. From 2003 onward…
   

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7. Bob McWhirter
   James Strachan
   

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8. Bob McWhirter
   James Strachan
   James Strachan and Bob McWhirter
   gave birth to Groovy: a dynamic and
   agile scripting language for the JVM.
   […] James always used to say that
   it was all Bob's fault, but indeed,
   James had so many groovy ideas that
   it's hard to believe it's not his own
   fault. He kept saying: "Wouldn't it
   be groovy if we could do this and
   that...". Hence the name "Groovy".
   That's roughly how it all started.
   

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10. 7
    Groovy pre-1.0
    • Closures available since 2003 on Java 1.4+
    • All the nice shortcuts already, inspired by Python & Ruby
    • native syntax for lists, maps, etc…
    • Tons of useful methods to simplify 

    common Java boiler-plate code
    • Initially dynamically-typed only
    

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12. I join the project in
    2003, patches after
    patches, become
    committer, then lead
    when founders left
    

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15. 11
    Groovy in 2004
    • A brand new parser based on Antlr
    • after two hand-rolled versions
    • by John Rose and Jeremy Rainer
    • Jochen « blackdrag » Theodorou joins the project
    

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22. 17
    First paid committer
    • Jochen becomes the first full-time paid committer
    • sponsored by BigSky Technologies / No Fluff Just Stuff
    

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25. 1.0
    

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31. Spock
    the Enterprise
    testing framework
    

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32. 24
    Groovy in 2007 — Groovy 1.5
    • The long awaited Java 5 update
    • annotations, enums, generics…
    • Joint compiler!
    • Varargs support
    • Static imports (including import aliasing)
    • Named parameters without parentheses
    

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34. Paul King, #1 committer
    from 2007 to 2010, and
    overall #1 committer too!
    

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38. 29
    Griffon and Easyb
    

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39. 30
    Groovy++ fork!
    • Not the first fork, but 3rd
    • by Alex Tkachman (former G2One co-founder)
    • Big focus on static compilation
    • interesting playground for our forthcoming static type
    checking and static compilation support
    

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41. I can honestly say if
    someone had shown
    me the Programming
    Scala book back in
    2003, I’d probably
    have never created
    Groovy
    

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42. Have I had JPA
    back then,
    I would
    certainly not
    have created
    Hibernate!
    

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54. 39
    The Groovy Ecosystem grows…
    

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55. 40
    Groovy 1.6
    • Performance improvements with call-site caching
    • Multiple assignments
    • Optional return in if/else, try/catch, switch/case
    • More AST transformations
    • @Singleton, @Lazy, @Immutable, @Delegate
    • The Grape module system with @Grab
    • OSGi support
    

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56. 41
    Groovy 1.7
    • Nested and inner classes, and nested static classes
    • Missing annotation definition support
    • Power Asserts from Spock
    • Customize the Groovy Truth!
    • AST viewer and AST builder
    • SQL support improvements
    

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58. 43
    Groovy ecosystem marching on…
    GContracts
    

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62. 47
    More Groovy ecosystem…
    

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63. 48
    Groovy 1.8
    • Command chain expressions
    • GPars bundled with the Groovy distribution
    • Primitive calculation optimizations
    • Closures
    • as annotation parameters
    • currying, memoization and tail recursion
    • Built-in JSON support
    

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64. I’m joining the
    Groovy team!
    

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67. 52
    Groovy ecosystem continued…
    • Netflix
    • Asgard,
    • Zuul
    • LinkedIn Glu
    • GroovyStream
    

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68. 53
    Groovy 2.0
    • Static type checking and static compilation
    • type inference, flow typing…
    • « Project Coin » enhancements
    • binary literals, underscore in numbers, multicatch block
    • Initial « invoke dynamic » support
    • Modularity of the Groovy code base with modules
    

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71. 56
    Richer Groovy ecosystem…
    

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72. 57
    Groovy 2.1
    • Full « invoke dynamic » support
    • Type-checking extensions
    • Meta-annotations
    • @DelegatesTo annotation
    • Compiler customization scripts
    • Distribution bundling GPars 1.0
    

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73. 58
    Groovy 2.2
    • Implicit closure coercion to SAM types
    • Java lambda friendly!
    • Pre-compiled type checking extensions
    • @Memoized transformations for methods
    

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76. 61
    Groovy ecosystem
    

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77. 62
    Groovy 2.3
    • Traits!
    • Improved JDK 8 support
    • Drastic performance improvement for JSON
    • New AST transformations & improvements
    • @Builder,@Sortable,@SourceURI, @BaseScript
    • New markup template engine
    • More NIO support
    

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79. You’re
    fired!
    2015
    

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81. Oh by the
    way,
    Codehaus
    closes!
    

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82. ANY
    IMPACT?
    

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83. 2012 2013 2014 2015
    Downloads
    

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84. 2012 2013 2014 2015
    1.7M
    3M
    4.5M
    Downloads 12.7M
    

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85. 3.4 MILLIONS
    FROM MAVEN CENTRAL
    IN 4 MONTHS
    

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86. MAVEN
    CENTRAL
    ONLY
    

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87. MAVEN
    CENTRAL
    ONLY
    +BINTRAY
    

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88. 3 MILLIONS
    FROM BINTRAY
    

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89. 6.4 MILLIONS
    ALREADY IN
    2016 SO FAR
    

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90. GROOVY
    2.4
    

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91. 72
    Groovy 2.4 — Android support
    • Write your Android applications
    fully in Groovy!
    • Dedicated Gradle plugin
    

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92. 73
    Groovy 2.4 — Android support
    SwissKnife

    a dedicated 

    Groovy / Android 

    library
    

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93. 74
    Groovy 2.4 — Performance & bytecode
    • Improved bytecode
    • cheaper comparison operations
    • optimization of primitive type coercions with ‘as’
    • Reduced bytecode size
    • no MOP generated methods in static context
    • uneeded inner class distributor methods when no inner
    • timestamp removal
    • Reduced memory consumption
    

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94. 75
    Groovy 2.4 — Traits @SelfType
    class Component {

    void doSomething() {

    println "Done!"

    }

    }
    

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95. 75
    Groovy 2.4 — Traits @SelfType
    class Component {

    void doSomething() {

    println "Done!"

    }

    }
    import groovy.transform.*
    

    @SelfType(Component)

    @TypeChecked

    trait ComponentDecorator {

    void logAndDoSomething() {

    println "Going to do something"

    doSomething()

    }

    }
    

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96. 75
    Groovy 2.4 — Traits @SelfType
    class Component {

    void doSomething() {

    println "Done!"

    }

    }
    import groovy.transform.*
    

    @SelfType(Component)

    @TypeChecked

    trait ComponentDecorator {

    void logAndDoSomething() {

    println "Going to do something"

    doSomething()

    }

    }
    class ConcreteComponent

    extends Component

    implements ComponentDecorator {}

    

    def c = new ConcreteComponent()

    c.logAndDoSomething()
    

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97. 76
    Groovy 2.4 — GDK improvements
    • New methods
    • System.currentTimeSeconds()
    • List: removeAt(index), getIndices()
    • Collection: removeElement(Object)
    • Iterable: disjoin(), size(), dropRight(),
    takeRight()
    • More collection methods moved to iterator-based
    • Favor stream-like traversal methods leveraging iterables
    • Consistency for mutation in place vs new collection creation
    

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98. 77
    Groovy 2.4 — AST transformations
    • @ToString added includeSuperProperties parameter
    • Can define compilation phase for @ASTTest
    • @Synchronized supports explicit static locks used by
    instance methods if needed
    • Cleaned-up code for @AutoExternalizable and
    @EqualsAndHashCode when used with @CompileStatic
    • Improved Java integration for @Builder
    • @PackageScope allowed on constructors
    

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99. 78
    Groovy 2.4 — Groovysh improvements
    • Custom .rc and .profile scripts
    • instanceof completion
    • Static members completion only in a static context
    • Completion candidates in color
    • :set interpreterMode to remember locally-defined variables
    • :load command supports file names with spaces
    • Align arguments & flags with the groovy command
    • Script launch on startup & continue execution of Groovysh
    • Easier to subclass Groovysh for embedded reuse
    

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100. Here come the Indians!
     

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102. MESSAGE TO THE
     COMMUNITY
     

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103. HERE TO
     STAY
     

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104. HERE TO
     STAY
     INDEPENDENCE
     

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105. HERE TO
     STAY
     COMMUNITY
     ABOVE ALL
     INDEPENDENCE
     

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106. 83
     Top Level Project at Apache!
     • PMC & Incubator PMC voted for graduation
     • Apache Board agreed to the graduation!
     • (last November)
     • Call us Apache Groovy :-)
     • 2.4.6 was released on February 2016
     

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107. 84
     Entering the TIOBE index
     • 3 months in a row in the top-20 TIOBE index
     • 17th for January
     • 20th for February
     • 17th for March
     • 17th for April
     • 17th for May
     

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109. Little nuggets…
     

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110. 87
     Groovy 2.4.4/5/6 / 2.5
     • Improved compiler performance
     • with an ASM class reader
     • @Canonical becomes a meta-annotation
     • More control on the meta-annotation collector
     • New @MapConstructor transformation
     • Pre/post conditions for @TupleConstructor
     • Property validation in transformation parameters
     • @Delegate on getters
     • Further AST transformation improvements
     • JAXB marshal/unmarshal shortcuts
     

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111. 88
     @Canonical becomes a meta-annotation
     import groovy.transform.*

     

     @Canonical(includeNames = true)

     class Person {

     String name

     int age

     }

     

     assert new Person('Guillaume', 38).toString() ==

     'Person(name:Guillaume, age:38)'
     

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112. 88
     @Canonical becomes a meta-annotation
     import groovy.transform.*

     

     @Canonical(includeNames = true)

     class Person {

     String name

     int age

     }

     

     assert new Person('Guillaume', 38).toString() ==

     'Person(name:Guillaume, age:38)'
     includeNames
     from @ToString
     

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113. 89
     More control on annotation collector
     DUPLICATE
     Annotations from the annotation
     collection will always be inserted.
     PREFER_COLLECTOR
     Annotations from the collector will be
     added and any existing annotations with
     the same name will be removed.
     PREFER_EXPLICIT
     Annotations from the collector will be
     ignored if any existing annotations with
     the same name are found.
     PREFER_EXPLICIT_MERGED
     Annotations from the collector will be
     ignored if any existing annotations with
     the same name are found but any new
     parameters on the collector annotation
     will be added to existing annotations.
     PREFER_COLLECTOR_MERGED
     Annotations from the collector will be
     added and any existing annotations with
     the same name will be removed but any
     new parameters found within existing
     annotations will be merged into the
     added annotation.
     

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114. 90
     New @MapConstructor transformation
     import groovy.transform.*

     

     @TupleConstructor

     class Person {

     String first, last

     }

     

     @CompileStatic // optional

     @ToString(includeSuperProperties = true)

     @MapConstructor(pre = { super(args?.first, args?.last);

     args = args ?: [:] },

     post = { first = first?.toUpperCase() })

     class Author extends Person {

     String bookName

     }
     assert new Author(first: 'Dierk',
     last: 'Koenig',
     bookName: 'ReGinA').toString() ==
     'Author(ReGinA, DIERK, Koenig)'

     

     assert new Author().toString() ==
     'Author(null, null, null)'
     

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115. 90
     New @MapConstructor transformation
     import groovy.transform.*

     

     @TupleConstructor

     class Person {

     String first, last

     }

     

     @CompileStatic // optional

     @ToString(includeSuperProperties = true)

     @MapConstructor(pre = { super(args?.first, args?.last);

     args = args ?: [:] },

     post = { first = first?.toUpperCase() })

     class Author extends Person {

     String bookName

     }
     assert new Author(first: 'Dierk',
     last: 'Koenig',
     bookName: 'ReGinA').toString() ==
     'Author(ReGinA, DIERK, Koenig)'

     

     assert new Author().toString() ==
     'Author(null, null, null)'
     Can decorate map
     ctor with pre / post-
     instructions
     

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116. 91
     Pre/post events for @TupleConstructor
     import groovy.transform.TupleConstructor
     @TupleConstructor(pre = { first = first?.toLowerCase() })
     class Person {
     String first
     }
     def p = new Person('Jack')
     assert p.first == 'jack'
     

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117. 91
     Pre/post events for @TupleConstructor
     import groovy.transform.TupleConstructor
     @TupleConstructor(pre = { first = first?.toLowerCase() })
     class Person {
     String first
     }
     def p = new Person('Jack')
     assert p.first == 'jack'
     import groovy.transform.TupleConstructor
     import static groovy.test.GroovyAssert.shouldFail
     @TupleConstructor(pre = { assert first })
     class Person {
     String first
     }
     def p = new Person('Jack')
     shouldFail {
     def unknown = new Person()
     }
     

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118. 92
     Properties validated in AST xforms
     import groovy.transform.AutoClone

     

     @AutoClone(excludes = 'sirName')

     class Person {

     String firstName

     String surName

     }

     

     new Person(firstName: "John",
     surName: "Doe").clone()
     

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119. 92
     Properties validated in AST xforms
     import groovy.transform.AutoClone

     

     @AutoClone(excludes = 'sirName')

     class Person {

     String firstName

     String surName

     }

     

     new Person(firstName: "John",
     surName: "Doe").clone()
     Error during @AutoClone
     processing: 'excludes'
     property 'sirName'
     does not exist.
     

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120. 93
     Prevent @TupleConstructor default ctors
     @TupleConstructor

     class Person {

     String first, last

     int age

     }
     

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121. 93
     Prevent @TupleConstructor default ctors
     @TupleConstructor

     class Person {

     String first, last

     int age

     }
     Generates:
     Person(String first, String last, int age) { /*...*/ }
     Person(String first, String last) { this(first, last, 0) }
     Person(String first) { this(first, null) }
     Person() { this(null) }
     

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122. 94
     Prevent @TupleConstructor default ctors
     @TupleConstructor(defaults = true)

     class Person {
     String first, last

     int age

     }
     

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123. 94
     Prevent @TupleConstructor default ctors
     @TupleConstructor(defaults = true)

     class Person {
     String first, last

     int age

     }
     Generates only:
     Person(String first, String last, int age) { /*...*/ }
     

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124. 95
     @Immutable support in class hierarchy
     import groovy.transform.*

     

     @EqualsAndHashCode

     class Person {

     String name

     }
     

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125. 95
     @Immutable support in class hierarchy
     import groovy.transform.*

     

     @EqualsAndHashCode

     class Person {

     String name

     }
     @Immutable

     @TupleConstructor(includeSuperProperties = true)

     @EqualsAndHashCode(callSuper = true)

     @ToString(includeNames = true, includeSuperProperties = true)

     class Athlete extends Person {

     String sport

     }
     

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126. 95
     @Immutable support in class hierarchy
     import groovy.transform.*

     

     @EqualsAndHashCode

     class Person {

     String name

     }
     @Immutable

     @TupleConstructor(includeSuperProperties = true)

     @EqualsAndHashCode(callSuper = true)

     @ToString(includeNames = true, includeSuperProperties = true)

     class Athlete extends Person {

     String sport

     }
     def d1 = new Athlete('Michael Jordan', 'BasketBall')

     def d2 = new Athlete(name: 'Roger Federer', sport: ‘Tennis')
     assert d1 != d2

     assert d1.toString() == 

     'Athlete(sport:BasketBall, name:Michael Jordan)'

     assert d2.toString() == 

     'Athlete(sport:Tennis, name:Roger Federer)'
     

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127. 96
     :grab command in groovysh
     groovy:000> :grab 'com.google.guava:guava:19.0'
     groovy:000> import com.google.common.collect.BiMap
     ===> com.google.common.collect.BiMap
     

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128. 97
     @Delegate on getters too
     class Person {

     String name
     @Delegate

     String getName() {
     name.toUpperCase()
     }
     }
     def p = new Person('Bill')
     assert p.toUpperCase() == 'BILL'
     

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129. 98
     JAXB marshalling shortcuts
     import groovy.transform.EqualsAndHashCode
     import javax.xml.bind.JAXBContext
     import javax.xml.bind.annotation.*
     @EqualsAndHashCode
     @XmlAccessorType(XmlAccessType.FIELD)
     @XmlRootElement
     class Person {
     String name
     int age
     }
     

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130. 98
     JAXB marshalling shortcuts
     import groovy.transform.EqualsAndHashCode
     import javax.xml.bind.JAXBContext
     import javax.xml.bind.annotation.*
     @EqualsAndHashCode
     @XmlAccessorType(XmlAccessType.FIELD)
     @XmlRootElement
     class Person {
     String name
     int age
     }
     def jaxbContext =
     JAXBContext.newInstance(Person)
     def p = new Person(name: 'Bill', age: 20)
     def xml = jaxbContext.marshal(p)
     assert jaxbContext.unmarshal(xml, Person) == p
     

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131. 99
     Miscellaneous
     • Map#retainAll {} and Map#removeAll {} methods
     • GDK’s createSimilarCollection() and
     createSimilarMap() methods support all the JDK’s
     collections and maps
     • New File#relativePath(file) method
     

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132. To conclude…
     

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134. It’s been a long road!
     And it’s not over yet!
     

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136. Thanks for your attention!
     

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137. Questions & Answers
     

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