Groovy Update - Guillaume Laforge - Greach 2011
Upcoming SlideShare
Loading in...5
×
 

Groovy Update - Guillaume Laforge - Greach 2011

on

  • 1,950 views

Overview of the features of Groovy 1.8 and what is coming in the next major version.

Overview of the features of Groovy 1.8 and what is coming in the next major version.

Statistics

Views

Total Views
1,950
Slideshare-icon Views on SlideShare
1,700
Embed Views
250

Actions

Likes
0
Downloads
37
Comments
0

2 Embeds 250

http://greach.es 245
http://a0.twimg.com 5

Accessibility

Categories

Upload Details

Uploaded via as Adobe PDF

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Groovy Update - Guillaume Laforge - Greach 2011 Groovy Update - Guillaume Laforge - Greach 2011 Presentation Transcript

    • Whatʼs new in Groovy 1.8 and beyond?Guillaume LaforgeGroovy Project ManagerSpringSource, a division of VMwareTwitter: @glaforgeBlog: http://glaforge.appspot.comGoogle+: http://gplus.to/glaforge
    • Guillaume Laforge• Groovy Project Manager at VMware • Initiator of the Grails framework • Creator of the Gaelyk toolkit• Co-author of Groovy in Action• Speaking worldwide w/ a French accent• Follow me on... • My blog: http://glaforge.appspot.com • Twitter: @glaforge • Google+: http://gplus.to/glaforge @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 2
    • Guillaume Laforge• Groovy Project Manager at VMware • Initiator of the Grails framework • Creator of the Gaelyk toolkit• Co-author of Groovy in Action• Speaking worldwide w/ a French accent• Follow me on... • My blog: http://glaforge.appspot.com • Twitter: @glaforge • Google+: http://gplus.to/glaforge @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 2
    • Groovy 1.7 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7185 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7185k @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7185k FIRST MONTH AFTER RELEASE @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7 k @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7177k SECOND MONTH AFTER RELEASE @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7 k @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • Groovy 1.7362k USERS? @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 3
    • ?TIP OFTHEICEBERG
    • Guesstimate 1/2 Users Million@glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 5
    • Agenda @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 6
    • Agenda• Whatʼs new in Groovy 1.8? – Nicer DSLs with command chains expressions – Runtime performance improvements – GPars bundled for taming your multicores – Closure enhancements – Builtin JSON support – New AST transformations @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 6
    • Agenda• Whatʼs new in Groovy 1.8? – Nicer DSLs with command chains expressions – Runtime performance improvements – GPars bundled for taming your multicores – Closure enhancements – Builtin JSON support – New AST transformations• Whatʼs cooking for Groovy 1.9? – Continued runtime performance improvements – Alignments with JDK 7 • Project Coin (small language changes) • Static type checking • InvokeDynamic @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 6
    • Command chains expressions @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions• A grammar improvement allowing you to drop dots & parens when chaining method calls – an extended version of top-level statements like println @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions• A grammar improvement allowing you to drop dots & parens when chaining method calls – an extended version of top-level statements like println @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions• A grammar improvement allowing you to drop dots & parens when chaining method calls – an extended version of top-level statements like println• Less dots, less parens allow you to – write more readable business rules – in almost plain English sentences • (or any language, of course) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions• A grammar improvement allowing you to drop dots & parens when chaining method calls – an extended version of top-level statements like println• Less dots, less parens allow you to – write more readable business rules – in almost plain English sentences • (or any language, of course) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions• A grammar improvement allowing you to drop dots & parens when chaining method calls – an extended version of top-level statements like println• Less dots, less parens allow you to – write more readable business rules – in almost plain English sentences • (or any language, of course)• Letʼs have a look at some examples @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 7
    • Command chains expressions  turn left  then right  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 8
    • Command chains expressions Alternation of method names  turn left  then right  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 8
    • Command chains expressions Alternation of method names  turn left  then right  and parameters (even named ones) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 8
    • Command chains expressions  turn left  then right  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 8
    • Command chains expressions Equivalent to:      (    ).    (     )  turn left  then right  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 8
    • LookM a!N op are ns,no do ts!
    • Command chains expressions Before... we used to do... take 2.pills, of: chloroquinine, after: 6.hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 10
    • Command chains expressions Before... we used to do... take 2.pills, of: chloroquinine, after: 6.hours Normal argument @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 10
    • Command chains expressions Before... we used to do... take 2.pills, of: chloroquinine, after: 6.hours Normal argument Named arguments @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 10
    • Command chains expressions Before... we used to do... take 2.pills, of: chloroquinine, after: 6.hours Normal argument Named arguments Woud call: def take(Map m, Quantity q) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 10
    • Command chains expressions Now, even less punctuation! take 2.pills  of  chloroquinine  after  6.hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 11
    • Command chains expressions Now, even less punctuation!     (       ).   (             ).      (       ) take 2.pills  of  chloroquinine  after  6.hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 11
    • Command chains expressions // environment initialization Integer.metaClass.getPills { ‐> delegate } Integer.metaClass.getHours { ‐> delegate }   // variable injection def chloroquinine = /*...*/   { } // implementing the DSL logic def take(n) {     [of: { drug ‐>         [after: { time ‐> /*...*/ }]     }] } // ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ take 2.pills of chloroquinine after 6.hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 12
    • Command chains expressions take 2.pills  of  chloroquinine  after  6.hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 13
    • Command chains expressions take 2.pills  of  chloroquinine  after  6.hours ... some dots remain ... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 13
    • Command chains expressions Yes, we can... get rid of them :-) take 2  pills of  chloroquinine  after  6 hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 14
    • Command chains expressions Yes, we can... get rid of them :-)     ( ).     (  ).              (     ). (     ) take 2  pills of  chloroquinine  after  6 hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 14
    • Command chains expressions // variable injection def (of, after, hours) = /*...*/   // implementing the DSL logic { } def take(n) {     [pills: { of ‐>         [chloroquinine: { after ‐>             [6: { time ‐> }]         }]     }] } // ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ take 2 pills of chloroquinine after 6 hours @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 15
    • Command chains expressions @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens select all  unique() from names @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens select all  unique() from names // possible with an odd number of terms @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens select all  unique() from names // possible with an odd number of terms take 3  cookies @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor     (      ).    (           ).   (      ) // leverage named‐args as punctuation check that: margarita  tastes good // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens select all  unique() from names // possible with an odd number of terms take 3  cookies @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor     (      ).    (           ).   (      ) // leverage named‐args as punctuation check that: margarita  tastes good      (               ).      (    ) // closure parameters for new control structures given {}  when {}  then {} // zero‐arg methods require parens select all  unique() from names // possible with an odd number of terms take 3  cookies @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor     (      ).    (           ).   (      ) // leverage named‐args as punctuation check that: margarita  tastes good      (               ).      (    ) // closure parameters for new control structures given {}  when {}  then {}      (  ).    (  ).    (  ) // zero‐arg methods require parens select all  unique() from names // possible with an odd number of terms take 3  cookies @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor     (      ).    (           ).   (      ) // leverage named‐args as punctuation check that: margarita  tastes good      (               ).      (    ) // closure parameters for new control structures given {}  when {}  then {}      (  ).    (  ).    (  ) // zero‐arg methods require parens select all  unique() from names       (   ).        .    (     ) // possible with an odd number of terms take 3  cookies @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Command chains expressions // methods with multiple arguments (commas) take coffee  with sugar, milk  and liquor     (      ).    (           ).   (      ) // leverage named‐args as punctuation check that: margarita  tastes good      (               ).      (    ) // closure parameters for new control structures given {}  when {}  then {}      (  ).    (  ).    (  ) // zero‐arg methods require parens select all  unique() from names       (   ).        .    (     ) // possible with an odd number of terms take 3  cookies     ( ). @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 16
    • Runtime performance improvements• Significant runtime improvements for primitive type operations – classical Fibonacci example x13 faster! – almost as fast as Java• Some direct method calls on this @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 17
    • GPars bundled• GPars is bundled in the Groovy distribution• GPars covers a wide range of parallel and concurrent paradigms – actors, fork/join, map/filter/reduce, dataflow, agents, STM – parallel arrays, executors, and more... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 18
    • Closure enhancements• Closure annotation parameters• Some more functional flavor – composition – trampoline – memoization• Currying improvements @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 19
    • Closure annotation parameters @Retention(RetentionPolicy.RUNTIME) @interface Invariant {         Class value() // a closure class }  { @Invariant({ number >= 0 }) class Distance {         float number         String unit }    def d = new Distance(number: 10, unit: "meters")  def anno = Distance.getAnnotation(Invariant) def check = anno.value().newInstance(d, d) assert check(d) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 20
    • Closure annotation parameters @Retention(RetentionPolicy.RUNTIME) @interface Invariant {         Class value() // a closure class }  { @Invariant({ number >= 0 }) class Distance {         float number     an’s G Cont racts     String unit P oor-m }    def d = new Distance(number: 10, unit: "meters")  def anno = Distance.getAnnotation(Invariant) def check = anno.value().newInstance(d, d) assert check(d) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 20
    • Closure composition def plus2  = { it + 2 } def times3 = { it * 3 }   { def times3plus2 = plus2 << times3 assert times3plus2(3) == 11 assert times3plus2(4) == plus2(times3(4))   { def plus2times3 = times3 << plus2 assert plus2times3(3) == 15 assert plus2times3(5) == times3(plus2(5))    // reverse composition{ assert times3plus2(3) == (times3 >> plus2)(3) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 21
    • Closure trampoline @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 22
    • Closure trampoline def factorial factorial = { int n, BigInteger accu = 1G ‐>        if (n < 2) return accu          factorial.trampoline(n ‐ 1, n * accu) }.trampoline()   assert factorial(1)    == 1 assert factorial(3)    == 1 * 2 * 3 assert factorial(1000) == 402387260... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 22
    • Closure memoization @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10)   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10)   // at most 10 invocations cached @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10)   // at most 10 invocations cached def plusAtMost = { ... }.memoizeAtMost(10)  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10)   // at most 10 invocations cached def plusAtMost = { ... }.memoizeAtMost(10)  // between 10 and 20 invocations cached @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Closure memoization def plus = { a, b ‐> sleep 1000; a + b }.memoize() assert plus(1, 2) == 3 // after 1000ms assert plus(1, 2) == 3 // return immediately assert plus(2, 2) == 4 // after 1000ms assert plus(2, 2) == 4 // return immediately     // at least 10 invocations cached def plusAtLeast = { ... }.memoizeAtLeast(10)   // at most 10 invocations cached def plusAtMost = { ... }.memoizeAtMost(10)  // between 10 and 20 invocations cached def plusAtLeast = { ... }.memoizeBetween(10, 20) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 23
    • Currying improvements @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 24
    • Currying improvements // right currying def divide = { a, b ‐> a / b } def halver = divide.rcurry(2) assert halver(8) == 4     @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 24
    • Currying improvements // right currying def divide = { a, b ‐> a / b } def halver = divide.rcurry(2) assert halver(8) == 4     // currying n‐th parameter def joinWithSeparator =      { one, sep, two ‐> one + sep + two } def joinWithComma =      joinWithSeparator.ncurry(1, , ) assert joinWithComma(a, b) == a, b @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 24
    • Builtin JSON support• Consuming• Producing• Pretty-printing @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 25
    • Builtin JSON supportimport groovy.json.* def payload = new URL(    "http://github.../json/commits/...").text def slurper = new JsonSlurper()def doc = slurper.parseText(payload) doc.commits.message.each { println it } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 26
    • Builtin JSON support import groovy.json.*    def json = new JsonBuilder()    json.person {         name "Guillaume"     age 33         pets "Hector", "Felix" }  println json.toString() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 27
    • Builtin JSON support import groovy.json.*    println JsonOutput.prettyPrint(     {"person":{"name":"Guillaume","age":33, +      "pets":["Hector","Felix"]}})   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 28
    • Builtin JSON support import groovy.json.*    println JsonOutput.prettyPrint(     {"person":{"name":"Guillaume","age":33, +      "pets":["Hector","Felix"]}})   {         "person": {                 "name": "Guillaume",              "age": 33,                 "pets": [                         "Hector",                         "Felix"                 ]         } } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 28
    • New AST transformations• @Log • @Canonical – @ToString,• @Field – @EqualsAndHashCode, – @TupleConstructor• @AutoClone• @AutoExternalizable • @InheritConstructor • @WithReadLock• Controlling the execution of your code • @WithWriteLock – @ThreadInterrupt, – @TimedInterrupt, • @ListenerList – @ConditionalInterrupt @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 29
    • @Log• Four different loggers can be injected – @Log, @Commons, @Log4j, @Slf4j• Possible to implement your own strategy import groovy.util.logging.*    @Log class Car {         Car() {                 log.info Car constructed         } }    def c = new Car() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 30
    • @Log• Four different loggers can be injected – @Log, @Commons, @Log4j, @Slf4j• Possible to implement your own strategy import groovy.util.logging.*    @Log class Car {     Guarded     Car() {         w/ an if         log.info Car constructed         } }    def c = new Car() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 30
    • @Field• Surprising scoping rules in scripts – variables are local to the run() method – variables arenʼt visible in methods • although visually the variable is in a surrounding scope• @Field creates a field in the script class @Field List awe = [1, 2, 3] def awesum() { awe.sum() } assert awesum() == 6 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 31
    • Controlling code execution• Your application may run userʼs code – what if the code runs in infinite loops or for too long? – what if the code consumes too many resources? @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 32
    • Controlling code execution• Your application may run userʼs code – what if the code runs in infinite loops or for too long? – what if the code consumes too many resources?• 3 new transforms at your rescue – @ThreadInterrupt: adds Thread#isInterrupted checks so your executing thread stops when interrupted – @TimedInterrupt: adds checks in method and closure bodies to verify itʼs run longer than expected – @ConditionalInterrupt: adds checks with your own conditional logic to break out from the user code @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 32
    • Controlling code execution• Your application may run userʼs code – what if the code runs in infinite loops or for too long? – what if the code consumes too many resources?• 3 new transforms at your rescue – @ThreadInterrupt: adds Thread#isInterrupted checks so your executing thread stops when interrupted – @TimedInterrupt: adds checks in method and closure bodies to verify itʼs run longer than expected – @ConditionalInterrupt: adds checks with your own conditional logic to break out from the user code @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 32
    • Controlling code execution• Your application may run userʼs code – what if the code runs in infinite loops or for too long? – what if the code consumes too many resources?• 3 new transforms at your rescue – @ThreadInterrupt: adds Thread#isInterrupted checks so your executing thread stops when interrupted – @TimedInterrupt: adds checks in method and closure bodies to verify itʼs run longer than expected – @ConditionalInterrupt: adds checks with your own conditional logic to break out from the user code• Also see compilation customizers later on @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 32
    • @ThreadInterrupt @ThreadInterrupt import groovy.transform.ThreadInterrupt    while (true) {     // eat lots of CPU } 33 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 33
    • @ThreadInterrupt @ThreadInterrupt import groovy.transform.ThreadInterrupt    while (true) { {     if (Thread.currentThread.isInterrupted())         throw new InterruptedException() }     // eat lots of CPU } 33 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 33
    • @ThreadInterrupt @ThreadInterrupt import groovy.transform.ThreadInterrupt    while (true) { {     if (Thread.currentThread.isInterrupted())         throw new InterruptedException() }     // eat lots of CPU }• Two optional annotation parameters available – checkOnMethodStart (true by default) – applyToAllClasses (true by default) 33 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 33
    • @TimedInterrupt @TimedInterrupt(10) import groovy.transform.TimedInterrupt    while (true) {     // eat lots of CPU }• InterruptedException thrown when checks indicate code ran longer than desired• Optional annotation parameters available – same as @ThreadInterrupt – value: for an amount of time duration – unit: for the time duration unit (TimeUnit.SECONDS) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 34
    • @ConditionalInterrupt• Specify your own condition to be inserted at the start of method and closure bodies – check for available resources, number of times run, etc.• Leverages closure annotation parameters from Groovy 1.8 @ConditionalInterrupt({ counter++ > 2 }) import groovy.transform.ConditionalInterrupt import groovy.transform.Field    @Field int counter = 0  100.times {         println executing script method... } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 35
    • @ToString• Provides a default toString() method to your types• Available annotation options – includeNames, includeFields, includeSuper, excludes import groovy.transform.ToString    @ToString class Person {         String name         int age }    println new Person(name: Pete, age: 15) // => Person(Pete, 15) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 36
    • @EqualsAndHashCode• Provides default implementations for equals() and hashCode() methods import groovy.transform.EqualsAndHashCode    @EqualsAndHashCode class Coord {         int x, y }    def c1 = new Coord(x: 20, y: 5) def c2 = new Coord(x: 20, y: 5)    assert c1 == c2 assert c1.hashCode() == c2.hashCode() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 37
    • @TupleConstructor• Provides a «classical» constructor with all properties• Several annotation parameter options available import groovy.transform.TupleConstructor    @TupleConstructor  class Person {         String name         int age }    def m = new Person(Marion, 3)         assert m.name == Marion assert m.age  == 3 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 38
    • @Canonical• One annotation to rule them all! – @Canonical mixes together • @ToString • @EqualsAndHashCode • @TupleConstructor• You can customize behavior by combining @Canonical and one of the other annotations @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 39
    • @InheritConstructor• Classes like Exception are painful when extended, as all the base constructors should be replicatedclass CustomException extends Exception {    CustomException()                        { super()       }    CustomException(String msg)              { super(msg)    }    CustomException(String msg, Throwable t) { super(msg, t) }    CustomException(Throwable t)             { super(t)      }} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 40
    • @InheritConstructor• Classes like Exception are painful when extended, as all the base constructors should be replicatedimport groovy.transform.*@InheritConstructorsclass CustomException extends Exception {    CustomException()                        { super()       }    CustomException(String msg)              { super(msg)    }    CustomException(String msg, Throwable t) { super(msg, t) }    CustomException(Throwable t)             { super(t)      }} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 40
    • @WithReadLock, @WithWriteLock import groovy.transform.*    class ResourceProvider {         private final Map<String, String> data = new HashMap<>()       @WithReadLock         String getResource(String key) {                 return data.get(key)         }            @WithWriteLock         void refresh() {                 //reload the resources into memory         } } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 41
    • @WithReadLock, @WithWriteLock import groovy.transform.*    class ResourceProvider {         private final Map<String, String> data = new HashMap<>()  {     @WithReadLock         String getResource(String key) {                 return data.get(key)         }       {     @WithWriteLock         void refresh() {                 //reload the resources into memory         } } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 41
    • Miscelanous• Compilation customizers• Java 7 diamond operator• Slashy and dollar slashy strings• New GDK methods• (G)String to Enum coercion @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 42
    • Compilation customizers• Ability to apply some customization to the Groovy compilation process• Three available customizers – ImportCustomizer – ASTTransformationCustomizer – SecureASTCustomizer• But you can implement your own @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 43
    • Imports customizer def configuration = new CompilerConfiguration()   def custo = new ImportCustomizer() custo.addStaticStar(Math.name) configuration.addCompilationCustomizers(custo)    def result = new GroovyShell(configuration)     .evaluate(" cos PI/3 ") @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 44
    • Applying an AST transformation def configuration = new CompilerConfiguration() configuration.addCompilationCustomizers(     new ASTTransformationCustomizer(Log))    new GroovyShell(configuration).evaluate("""     class Car {                 Car() {                         log.info Car constructed                 }         }          log.info Constructing a car         def c = new Car() """) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 45
    • Secure AST customizer Idea: Implement an «arithmetic shell» Being able control what a user script is allowed to do: only arithmetic expressions• Letʼs setup our environment – some imports – an import customizer to import java.lang.Math.* – prepare a secure AST customizerimport org.codehaus.groovy.control.customizers.*import org.codehaus.groovy.control.*import static org.codehaus.groovy.syntax.Types.* def imports = new ImportCustomizer().addStaticStars(java.lang.Math)def secure = new SecureASTCustomizer() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 46
    • Secure AST customizer ... secure.with { // disallow closure creation closuresAllowed = false  // disallow method definitions methodDefinitionAllowed = false    // empty white list => forbid imports importsWhitelist = []  staticImportsWhitelist = [] // only allow the java.lang.Math.* static import staticStarImportsWhitelist = [java.lang.Math ... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 47
    • Secure AST customizer... // language tokens allowed tokensWhitelist = [ PLUS, MINUS, MULTIPLY, DIVIDE, MOD, POWER, PLUS_PLUS,  MINUS_MINUS, COMPARE_EQUAL, COMPARE_NOT_EQUAL,  COMPARE_LESS_THAN, COMPARE_LESS_THAN_EQUAL,  COMPARE_GREATER_THAN, COMPARE_GREATER_THAN_EQUAL ]  // types allowed to be used (including primitive types) constantTypesClassesWhiteList = [ Integer, Float, Long, Double, BigDecimal,  Integer.TYPE, Long.TYPE, Float.TYPE, Double.TYPE ]  // classes who are allowed to be receivers of method calls receiversClassesWhiteList = [  Math, Integer, Float, Double, Long, BigDecimal ]}... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 48
    • Secure AST customizer• Ready to evaluate our arithmetic expressions! ... def config = new CompilerConfiguration() config.addCompilationCustomizers(imports, secure) def shell = new GroovyShell(config)   shell.evaluate cos PI/3• But the following would have failed: shell.evaluate System.exit(0) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 49
    • Slashy and dollar slashy strings• Slashy strings are now multiline – particularly handy for multi-line regexs• Dollar slashy string notation introduced – a multiline GString with different escaping rules def (name, date) = ["Guillaume", "Oct, 26th"] def dollarSlashy = $/         Hello $name, today were ${date}     $ dollar‐sign         $$ dollar‐sign          backslash         / slash        $/ slash /$  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 50
    • New GDK methods @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1   @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1   // map withDefault() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1   // map withDefault() def words = "one two two three three three".split() @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1   // map withDefault() def words = "one two two three three three".split() def freq = [:].withDefault { k ‐> 0 } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • New GDK methods // count assert [2,4,2,1,3,5,2,4,3].count { it % 2 == 0 } == 5   // count by assert [0:2, 1:3] == [1,2,3,4,5].countBy{ it % 2 } assert [(true):2, (false):4]      == Groovy.toList().countBy{ it == o }   // min/max for maps with closures def map = [a: 1, bbb: 4, cc: 5, dddd: 2]  assert map.max { it.key.size() }.key == dddd assert map.min { it.value }.value == 1   // map withDefault() def words = "one two two three three three".split() def freq = [:].withDefault { k ‐> 0 } words.each { freq[it] += 1 } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 51
    • (G)String to Enum coercion @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {     @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    // implicit coercion @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    // implicit coercion Color b = "blue"  @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    // implicit coercion Color b = "blue"    @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    // implicit coercion Color b = "blue"    // with GStrings too @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • (G)String to Enum coercion enum Color {         red, green, blue }    // coercion with as def r = "red" as Color    // implicit coercion Color b = "blue"    // with GStrings too def g = "${green}" as Color @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 52
    • Customizing the Groovysh prompt @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 53
    • Launching remote scripts• With the Groovy command, you can launch remote scripts > groovy http://groovyconsole.appspot.com/raw/110001• Be careful to what youʼre executing :-) @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 54
    • What’scookingfor 1.9?
    • Groovy 1.9 roadmap• Java 7 alignements: Project Coin – binary literals – underscore in literals – multicatch• JDK 7: InvokeDynamic• Towards a more modular Groovy• Static type checking and compilation• Miscelanous• What else? Your call! @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 56
    • Groovy 1.9 roadmap• Java 7 alignements: Project Coin – binary literals – underscore in literals – multicatch• JDK 7: InvokeDynamic• Towards a more modular Groovy• Static type checking and compilation• Miscelanous• What else? Your call! @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 56
    • Java 7 / JDK 7• Project Coin and InvokeDynamic @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 57
    • Binary literals• We had decimal, octal and hexadecimal notations for number literals• We can now use binary representations too int x = 0b10101111 assert x == 175   byte aByte = 0b00100001 assert aByte == 33   int anInt = 0b1010000101000101 assert anInt == 41285 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 58
    • Underscore in literals• Now we can also add underscores in number literals for more readability long creditCardNumber = 1234_5678_9012_3456L long socialSecurityNumbers = 999_99_9999L float monetaryAmount = 12_345_132.12 long hexBytes = 0xFF_EC_DE_5E long hexWords = 0xFFEC_DE5E long maxLong = 0x7fff_ffff_ffff_ffffL long alsoMaxLong = 9_223_372_036_854_775_807L long bytes = 0b11010010_01101001_10010100_10010010 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 59
    • Multicatch• One block for multiple exception caught – rather than duplicating the block try {     /* ... */ } catch(IOException | NullPointerException e) {     /* one block to treat 2 exceptions */ } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 60
    • InvokeDynamic• Groovy 1.9 will support JDK 7ʼs invokeDynamic – an «indy» branch started recently – compiler will have a flag for compiling against JDK 7• Benefits – more runtime performance! – in the long run, will allow us to get rid of code! • call site caching, thanks to MethodHandles • metaclass registry, thanks to ClassValues • will let the JIT inline calls more easily @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 61
    • Groovy Modularity• Groovyʼs «all» JAR weighs in at 4MB• Nobody needs everything – Template engine, Ant scripting, Swing UI building...• Provide a smaller core – and several smaller JARs per feature• Provide hooks for setting up EMCs / DGM methods, etc. @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 62
    • Static Type Checking• Goal: make the Groovy compiler «grumpy»! – and throw compilation errors (not at runtime)• Not everybody needs dynamic features all the time – think Java libraries scripting• Grumpy should... – tell you about your method or variable typos – complain if you call methods that donʼt exist – shout on assignments of wrong types – infer the types of your variables – figure out GDK methods – etc... @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 63
    • A typo in your variable or method namesimport groovy.transform.StaticTypes void method() {} @TypeChecked test() {    // Cannot find matching method metthhoood()    metthhoood()     def name = "Guillaume"    // variable naamme is undeclared    println naamme} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 64
    • A typo in your variable or method namesimport groovy.transform.StaticTypes void method() {} @TypeChecked test() {    // Cannot find matching method metthhoood()    metthhoood()     def name = "Guillaume"    // variable naamme is undeclared Compilation    println naamme errors!} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 64
    • Complain on wrong assignments// cannot assign value of type... to variable...int x = new Object()Set set = new Object() def o = new Object()int x = o String[] strings = [a,b,c]int str = strings[0] // cannot find matching method plus()int i = 0i += 1 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 65
    • Complain on wrong assignments// cannot assign value of type... to variable...int x = new Object()Set set = new Object() Compilation  errors!def o = new Object()int x = o String[] strings = [a,b,c]int str = strings[0] // cannot find matching method plus()int i = 0i += 1 @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 65
    • Complain on wrong return typesString method() { String }// cannot assign value of type String...int x = method()// checks if/else branch return valuesint method() {    if (true) { String }    else { 42 }}// works for switch/case & try/catch/finally // transparent toString() impliedString greeting(String name) {    def sb = new StringBuilder()    sb << "Hi" << name} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 66
    • Complain on wrong return typesString method() { String }// cannot assign value of type String...int x = method() Compilation errors!// checks if/else branch return valuesint method() {    if (true) { String }    else { 42 }}// works for switch/case & try/catch/finally // transparent toString() impliedString greeting(String name) {    def sb = new StringBuilder()    sb << "Hi" << name} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 66
    • Type inference @TypeChecked test() {     def name = "  Guillaume  "       // String type infered (even inside GString)     println "NAME = ${name.toUpperCase()}"        // Groovy GDK method support     // (GDK operator overloading too)     println name.trim()       int[] numbers = [1, 2, 3]     // Element n is an int     for (int n in numbers) {         println n     } } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 67
    • Staticly checked method & dynamic method @TypeChecked String greeting(String name) {     // call method with dynamic behavior     // but with proper signature     generateMarkup(name.toUpperCase()) }   // usual dynamic behavior String generateMarkup(String name) {     def sw = new StringWriter()     new MarkupBuilder(sw).html {         body {             div name         }     }     sw.toString() } @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 68
    • Bytecode viewer• Groovy Consoleʼs bytecode viewer from the AST browser window – select class generation phase – select a class node @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 69
    • Disable Global AST transformations// witout a specific configuration, the AST builder worksdef shell = new GroovyShell()shell.evaluate(script) // passesdef config = new CompilerConfiguration()config.disabledGlobalASTTransformations =    [org.codehaus.groovy.ast.builder.AstBuilderTransformation]def script =     import org.codehaus.groovy.ast.builder.AstBuilder    new AstBuilder().buildFromCode { "Hello" } // now with the configuration in place,// the AST builder transform is not appliedshell = new GroovyShell(config) // <‐‐ with the configurationshouldFail {    shell.evaluate(script) // fails} @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 70
    • Summary @glaforge — http://glaforge.appspot.com ROCKS! — http://gplus.to/glaforge 71
    • Thank you! e L aforg pment aume vy Develo Guill Groo m Hea d of g mail.co aforge@ mail: gl glaforge e E @ o /glaforg T witter : http://gplus.t Go ogle+: @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 72
    • Q&A — Got questions, Really?
    • Image credits• Iceberg: http://hqworld.net/gallery/data/media/20/tip_of_the_iceberg.jpg• Bicycle: http://drunkcyclist.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=2131&g2_serialNumber=2• Pills: http://www.we-ew.com/wp-content/uploads/2011/01/plan-b-pills.jpg• Chains: http://2.bp.blogspot.com/-GXDVqUYSCa0/TVdBsON4tdI/AAAAAAAAAW4/EgJOUmAxB28/s1600/breaking-chains5_copy9611.jpg• Cooking: http://www.flickr.com/photos/eole/449958332/sizes/l/• Oui nide iou: http://desencyclopedie.wikia.com/wiki/Fichier:Superdupont_we_need_you.jpg• Guitar: http://www.lelitteraire.com/IMG/breveon323.jpg• Trampoline: http://www.fitness-online.fr/images/trampoline-1-m.jpg• Curry: http://www.pot-a-epices.com/wp-content/uploads/2009/02/curry1.jpg• Slurp: http://www.ohpacha.com/218-532-thickbox/gamelle-slurp.jpg• Caution: http://www.jeunes-epinay-sur-seine.fr/wp-content/uploads/2010/11/caution-colocation.jpg• Grumpy: http://mafeuilledechou.fr/__oneclick_uploads/2010/05/grumpy.jpg• Modularity: http://php.jglobal.com/blog/wp-content/uploads/2009/11/modularity.jpg• Agenda: http://www.plombiereslesbains.fr/images/stories/agenda.jpg• Java 7: http://geeknizer.com/wp-content/uploads/java7.jpg• WIP: http://www.connetport.com/wp-content/uploads/Work_in_progress.svg_.png• Grumpy 2: http://grumpy.division-par-zero.fr/wp-content/images/grumpy.jpg• @glaforge — http://glaforge.appspot.com — http://gplus.to/glaforge 74