Presented at GeeCON 2011: JavaFX Script is going away, but the JavaFX Platform is getting a new face with pure Java APIs. In this session, you will see how you can leverage the new JavaFX 2.0 APIs from a host of different JVM languages, including JRuby, Clojure, Groovy, and Scala.

1. JavaFX 2.0 With Alternative Languages - Groovy, Clojure, Scala, Fantom, and Visage Stephen Chin Chief Agile Methodologist, GXS steveonjava@gmail.com tweet: @steveonjava

2. About the Presenter Stephen Chin Java Champion Family Man Chief Agile Methodologist, GXS Author, Pro JavaFX Platform OSCON Java Conference Chair Motorcyclist

3. Disclaimer: This is code-heavy THE FOLLOWING IS INTENDED TO STIMULATE CREATIVE USE OF JVM LANGUAGES. AFTER WATCHING THIS PRESENTATION YOU MAY FEEL COMPELLED TO START LEARNING A NEW JVM LANGUAGE AND WANT TO APPLY IT AT YOUR WORKPLACE. THE PRESENTERS ARE NOT LIABLE FOR ANY INNOVATION, BREAKTHROUGHS, OR NP-COMPLETE SOLUTIONS THAT MAY RESULT.

4. JavaFX With Java

5. Programming Languages JavaFX 2.0 APIs are now in Java Pure Java APIs for all of JavaFX Expose JavaFX Binding, Sequences as Java APIs Embrace all JVM languages JRuby, Clojure, Groovy, Scala Fantom, Mira, Jython, etc. JavaFX Script is no longer supported by Oracle Existing JavaFX Script based applications will continue to run Visage is the open-source successor to the JavaFX Script language

6. JavaFX in Java JavaFX API follows JavaBeans approach Similar in feel to other UI toolkits (Swing, etc) Uses builder pattern to minimize boilerplate

7. Example Application public class HelloStage extends Application { @Override public void start(Stage stage) { stage.setTitle("Hello Stage"); stage.setWidth(600); stage.setHeight(450); Group root = new Group(); Scene scene = new Scene(root); scene.setFill(Color.LIGHTGREEN); stage.setScene(scene); stage.setVisible(true); } public static void main(String[] args) { Launcher.launch(HelloStage.class, args); } }

8. Binding Unquestionably the biggest JavaFX Script innovation Supported via a PropertyBinding class Lazy invocation for high performance Static construction syntax for simple cases e.g.: bindTo(<property>)

9. Observable Pseudo-Properties Supports watching for changes to properties Implemented via anonymous inner classes Will take advantage of closures in the future

10. Observable Pseudo-Properties final Rectangle rect = new Rectangle(); rect.setX(40); rect.setY(40); rect.setWidth(100); rect.setHeight(200); rect.hoverProperty().addListener(new ChangeListener<Boolean>() { });

11. Observable Pseudo-Properties final Rectangle rect = new Rectangle(); rect.setX(40); rect.setY(40); rect.setWidth(100); rect.setHeight(200); rect.hoverProperty().addListener(new ChangeListener<Boolean>() { }); The property we want to watch

12. Observable Pseudo-Properties final Rectangle rect = new Rectangle(); rect.setX(40); rect.setY(40); rect.setWidth(100); rect.setHeight(200); rect.hoverProperty().addListener(new ChangeListener<Boolean>() { }); Only one listener used with generics to specify the data type

13. Observable Pseudo-Properties final Rectangle rect = new Rectangle(); rect.setX(40); rect.setY(40); rect.setWidth(100); rect.setHeight(200); rect.hoverProperty().addListener(new ChangeListener<Boolean>() { public void changed(ObservableValue<? extends Boolean> property, Boolean oldValue, Boolean value) { } }); Refers to the Rectangle.hoverProperty()

14. Observable Pseudo-Properties final Rectangle rect = new Rectangle(); rect.setX(40); rect.setY(40); rect.setWidth(100); rect.setHeight(200); rect.hoverProperty().addListener(new ChangeListener<Boolean>() { public void changed(ObservableValue<? extends Boolean> property, Boolean oldValue, Boolean value) { rect.setFill(rect.isHover() ? Color.GREEN : Color.RED); } });

15. Sequences in Java Replaced with an Observable List Public API is based on JavaFX sequences Internal code can use lighter collections API JavaFX 2.0 also has an Observable Map

16. JavaFX With JRuby

18. Dynamic Typing

19. Closures

21. JRuby Example 1: Simple Stage require 'java' Application = Java::javafx.application.Application Launcher = Java::javafx.application.Launcher Stage = Java::javafx.stage.Stage Scene = Java::javafx.scene.Scene Color = Java::javafx.scene.paint.Color class HelloStage< Application def start(stage) ..... end end Launcher.launch(HelloStage.new); stage.title = 'Hello Stage (JRuby)' stage.width = 600 stage.height = 450 scene = Scene.new scene.fill = Color::LIGHTGREEN stage.scene = scene stage.visible = true;

22. JRuby Example 2 rect = Rectangle.new rect.x = 25 rect.y = 40 rect.width = 100 rect.height = 50 rect.fill = Color::RED scene.content.add(rect) timeline = Timeline.new timeline.repeat_count= Timeline::INDEFINITE timeline.auto_reverse = true kv = KeyValue.new(rect, Rectangle::X, 200); kf = KeyFrame.new(Duration.valueOf(500), kv); timeline.key_frames.addkf; timeline.play();

23. JRuby Closure Conversion rect.hoverProperty.addListener() do |prop, oldVal, newVal| rect.fill = rect.hover ? Color::GREEN : Color::RED; end 21

24. JRubySwiby require 'swiby' class HelloWorldModel attr_accessor :saying end model = HelloWorldModel.new model.saying = "Hello World" Frame { title "Hello World“ width 200 content { Label { text bind(model,:saying) } } visible true } 22

25. 23 JavaFX With Clojure Artwork by Augusto Sellhorn http://sellmic.com/

26. A Little About Clojure Started in 2007 by Rich Hickey Functional Programming Language Derived from LISP Optimized for High Concurrency … and looks nothing like Java! 24 (def hello (fn [] "Hello world")) (hello)

27. Clojure Syntax in One Slide Symbols numbers – 2.178 ratios – 355/113 strings – “clojure”, “rocks” characters – symbols – a b c d keywords – :alpha :beta boolean – true, false null - nil Collections (commas optional) Lists (1, 2, 3, 4, 5) Vectors [1, 2, 3, 4, 5] Maps {:a 1, :b 2, :c 3, :d 4} Sets #{:a :b :c :d :e} 25 (plus macros that are syntactic sugar wrapping the above)

28. Clojure GUI Example (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (.setFill scene Color/LIGHTGREEN) (.setWidth stage 600) (.setHeight stage 450) (.setScene stage scene) (.setVisible stage true))) (javafxapp) 26

29. Clojure GUI Example (defnjavafxapp[] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (.setFill scene Color/LIGHTGREEN) (.setWidth stage 600) (.setHeight stage 450) (.setScene stage scene) (.setVisible stage true))) (javafxapp) 27 Create a Function for the Application

30. Clojure GUI Example (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (.setFill scene Color/LIGHTGREEN) (.setWidth stage 600) (.setHeight stage 450) (.setScene stage scene) (.setVisible stage true))) (javafxapp) 28 Initialize the Stage and Scene Variables

31. Clojure GUI Example (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (.setFill scene Color/LIGHTGREEN) (.setWidth stage 600) (.setHeight stage 450) (.setScene stage scene) (.setVisible stage true))) (javafxapp) 29 Call Setter Methods on Scene and Stage

32. Clojure GUI Example (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (.setFillscene Color/LIGHTGREEN) (.setWidthstage 600) (.setHeightstage 450) (.setScenestage scene) (.setVisiblestage true))) (javafxapp) 30 Java Constant Syntax Java Method Syntax

33. Simpler Code Using doto (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (doto scene (.setFillColor/LIGHTGREEN)) (doto stage (.setWidth600) (.setHeight450) (.setScene scene) (.setVisibletrue)))) (javafxapp) 31

34. Simpler Code Using doto (defnjavafxapp [] (let [stage (Stage. "JavaFX Stage") scene (Scene.)] (doto scene (.setFillColor/LIGHTGREEN)) (doto stage (.setWidth 600) (.setHeight 450) (.setScene scene) (.setVisible true)))) (javafxapp) 32 doto form: (doto symbol (.method params)) equals: (.method symbol params)

35. Refined Clojure GUI Example (defnjavafxapp [] (doto (Stage. "JavaFX Stage") (.setWidth600) (.setHeight450) (.setScene (doto (Scene.) (.setFillColor/LIGHTGREEN) (.setContent (list (doto (Rectangle.) (.setX25) (.setY40) (.setWidth100) (.setHeight50) (.setFillColor/RED)))))) (.setVisibletrue))) (javafxapp) 33

36. Refined Clojure GUI Example (defnjavafxapp [] (doto(Stage. "JavaFX Stage") (.setWidth 600) (.setHeight 450) (.setScene (doto(Scene.) (.setFillColor/LIGHTGREEN) (.setContent (list (doto (Rectangle.) (.setX 25) (.setY 40) (.setWidth 100) (.setHeight 50) (.setFillColor/RED)))))) (.setVisible true))) (javafxapp) 34 Let replaced with inline declarations

37. Refined Clojure GUI Example (defnjavafxapp [] (doto (Stage. "JavaFX Stage") (.setWidth 600) (.setHeight 450) (.setScene (doto (Scene.) (.setFillColor/LIGHTGREEN) (.setContent (list (doto (Rectangle.) (.setX 25) (.setY 40) (.setWidth 100) (.setHeight 50) (.setFillColor/RED)))))) (.setVisible true))) (javafxapp) 35 Doto allows nested data structures

38. Refined Clojure GUI Example (defnjavafxapp [] (doto (Stage. "JavaFX Stage") (.setWidth 600) (.setHeight 450) (.setScene (doto (Scene.) (.setFillColor/LIGHTGREEN) (.setContent (list (doto (Rectangle.) (.setX 25) (.setY 40) (.setWidth 100) (.setHeight 50) (.setFillColor/RED)))))) (.setVisible true))) (javafxapp) 36 Now a nested Rectangle fits!

39. Closures in Clojure 37 Inner classes can be created using proxy (.addListenerhoverProperty (proxy[ChangeListener] [] (handle [p, o, v] (.setFillrect (if (.isHoverrect) Color/GREEN Color/RED)))))

40. Closures in Clojure Inner classes can be created using proxy 38 Proxy form: (proxy [class] [args] fs+) f => (name [params*] body) (.addListenerhoverProperty (proxy[ChangeListener][] (handle [p, o, v] (.setFillrect (if (.isHoverrect) Color/GREEN Color/RED)))))

41. JavaFX With Groovy

42. Features of Groovy Tight integration with Java Very easy to port from Java to Groovy Declarative syntax Familiar to JavaFX Script developers Builders

43. Example 1: Simple FX Script to Groovy

44. Step 1: Lazy conversion to Groovy class HelloStage extends Application { void start(stage) { stage.setTitle("Hello Stage (Groovy)“); stage.setWidth(600); stage.setHeight(450); Scene scene = new Scene(); scene.setFill(Color.LIGHTSKYBLUE); stage.setScene(scene); stage.setVisible(true); } static void main(args) { Launcher.launch(HelloStage.class, args); } }

45. Step 2: Slightly More Groovy class HelloStage extends Application { void start(stage) { new Stage( title: "Hello Stage (Groovy)", width: 600, height: 450, visible: true, scene: new Scene( fill: Color.LIGHTSKYBLUE, ) ); } static void main(args) { Launcher.launch(HelloStage.class, args); } }

46. Slight Aside: Groovy Builders Groovy builders make writing custom DSLs easy For the next slide, I am using a builder I defined Hopefully the community will improve upon this

47. Step 3: Using a Groovy Builder FxBuilder.build { stage = stage( title: "Hello World", width: 600, height: 450, scene: scene(fill: Color.LIGHTSKYBLUE) { ... } ) stage.visible = true; }

48. Step 4: With Content FxBuilder.build { stage = stage( title: "Hello Rectangle (Groovy FxBuilder 2)", width: 600, height: 450, scene: scene(fill: Color.LIGHTSKYBLUE) { rectangle( x: 25, y: 40, width: 100, height: 50, fill: Color.RED ) } ) stage.visible = true; }

49. Example 2: FX Script Animation in Groovy

50. Step 1: JavaFX Script def timeline = Timeline { repeatCount: Timeline.INDEFINITE autoReverse: true keyFrames: [ KeyFrame { time: 750ms values : [ rect1.x => 200.0 tweenInterpolator.LINEAR, rect2.y => 200.0 tweenInterpolator.LINEAR, circle1.radius => 200.0 tweenInterpolator.LINEAR ] } ]; } timeline.play();

51. Step 1a: JavaFX Script Simplification def timeline = Timeline { repeatCount: Timeline.INDEFINITE autoReverse: true keyFrames: at (750ms) { rect1.x => 200.0 tween Interpolator.LINEAR; rect2.y => 200.0 tween Interpolator.LINEAR; circle1.radius => 200.0 tween Interpolator.LINEAR; } } timeline.play();

52. Step 2: Java-ish Groovy Animations final Timeline timeline = new Timeline( repeatCount: Timeline.INDEFINITE, autoReverse: true ) final KeyValue kv1 = new KeyValue (rect1.x(), 200); final KeyValue kv2 = new KeyValue (rect2.y(), 200); final KeyValue kv3 = new KeyValue (circle1.radius(), 200); final KeyFramekf = new KeyFrame(Duration.valueOf(750), kv1, kv2, kv3); timeline.getKeyFrames().add(kf); timeline.play();

53. Step 3: JavaFX Animation Groovy DSL (courtesy of Jim Clarke – work in progress) timeline = timeline(repeatCount: Timeline.INDEFINITE, autoReverse: true) { at 750.ms update values { change rect1.y() to 200 change rect2.x() to 200 change circle.radius() to 200 } } timeline.play();

54. Groovy Closures - With interface coercion def f = { p, o, v -> rect.setFill(rect.isHover() ? Color.GREEN : Color.RED); } as ChangeListener; rect.hoverProperty().addListener(f);

55. 53 JavaFX With Scala

56. What is Scala Started in 2001 by Martin Odersky Compiles to Java bytecodes Pure object-oriented language Also a functional programming language 54

57. Why Scala? Shares many language features with JavaFX Script that make GUI programming easier: Static type checking – Catch your errors at compile time Closures – Wrap behavior and pass it by reference Declarative – Express the UI by describing what it should look like Scala also supports DSLs! 55

58. Java vs. Scala DSL public class HelloStage extends Application { public void start(Stage stage) { stage.setTitle("Hello Stage"); stage.setWidth(600); stage.setHeight(450); Scene scene = new Scene(); scene.setFill(Color.LIGHTGREEN); Rectangle rect = new Rectangle(); rect.setX(25); rect.setY(40); rect.setWidth(100); rect.setHeight(50); rect.setFill(Color.RED); stage.add(rect); stage.setScene(scene); stage.setVisible(true); } public static void main(String[] args) { Launcher.launch(HelloStage.class, args); } } object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } 56 21 Lines 541 Characters 17 Lines 324 Characters

59. object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } 57

60. 58 object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } Base class for JavaFX applications

61. 59 object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } Declarative Stage definition

62. 60 object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } Inline property definitions

63. 61 object HelloJavaFX extends JavaFXApplication { def stage = new Stage { title = "Hello Stage" width = 600 height = 450 scene = new Scene { fill = Color.LIGHTGREEN content = List(new Rectangle { x = 25 y = 40 width = 100 height = 50 fill = Color.RED }) } } } List Construction Syntax

64. Animation in Scala def timeline = new Timeline { repeatCount = INDEFINITE autoReverse = true keyFrames = List( new KeyFrame(time: 50) { values = List( new KeyValue(rect1.x() -> 300), new KeyValue(rect2.y() -> 500), new KeyValue(rect2.width() -> 150) ) } ) } 62

65. def timeline = new Timeline { repeatCount = INDEFINITE autoReverse = true keyFrames = List( new KeyFrame(time: 50) { values = List( new KeyValue(rect1.x() -> 300), new KeyValue(rect2.y() -> 500), new KeyValue(rect2.width() -> 150) ) } ) } Animation in Scala 63 Duration set by Constructor Parameter

66. Animation in Scala 64 def timeline = new Timeline { repeatCount = INDEFINITE autoReverse = true keyFrames = List( new KeyFrame(time: 50) { values = List( new KeyValue(rect1.x() -> 300), new KeyValue(rect2.y() -> 500), new KeyValue(rect2.width() -> 150) ) } ) } Operator overloading for animation syntax

67. Closures in Scala 65 Closures are also supported in Scala And they are 100% type-safe rect.hoverProperty().addListener((p, o, v) => { rect.fill = if (rect.hover) Color.GREEN else Color.RED })

68. Closures in Scala Closures are also supported in Scala And they are 100% type-safe 66 rect.hoverProperty().addListener((p, o, v) => { rect.fill = if (rect.hover) Color.GREEN else Color.RED }) Compact syntax (params) => {body}

69. Other JVM Languages to Try Jython Started by Jim Hugunin High Performance Python Mirah Invented by Charles Nutter Originally called Duby Local Type Inference, Static and Dynamic Typing Fantom Created by Brian and Andy Frank Originally called Fan Built-in Declarative Syntax Portable to Java and .NET Local Type Inference, Static and Dynamic Typing 67

70. Fantom Code Example Void main() { Stage { title= "Hello Stage" width= 600 height= 450 Scene { fill= Color.LIGHTGREEN Rectangle { x= 25 y= 40 width= 100 height= 50 fill= Color.RED } } }.open } 68

71. timeline := Timeline { repeatCount = Timeline.INDEFINITE autoReverse = true KeyFrame { time = 50ms KeyValue(rect1.x()-> 300), KeyValue(rect2.y() -> 500), KeyValue(rect2.width() -> 150) } } Animation in Fantom 69 Fantom has a built-in Duration type And also supports operator overloading

73. How about JavaFX on… Visage Stage { title: "Hello Stage" width: 600 height: 450 scene: Scene { fill: Color.LIGHTGREEN content: Rectangle { x: 25 y: 40 width: 100 height: 50 fill: Color.RED } } } 71

74. How about JavaFX on… Visage Stage { title: "Hello Stage" width: 600 height: 450 scene: Scene { fill: Color.LIGHTGREEN content: Rectangle { x: 25 y: 40 width: 100 height: 50 fill: Color.RED } } } 72

75. How about JavaFX on… Visage Stage { title: "Hello Stage" width: 600 height: 450 Scene { fill: Color.LIGHTGREEN Rectangle { x: 25 y: 40 width: 100 height: 50 fill: Color.RED } } } 73

76. Conclusion You can write JavaFX applications in pure Java JavaFX is also usable in alternate languages Over time improved support is possible Groovy Builders, Scala DSL, Visage Remember: This is a proof of concept only – you can not leave this session and do this today.

77. JavaFX 2.0 Product Timeline CYQ1 2011 CYQ3 2011 CYQ2 2011 JavaFX 2.0 EA (Early Access) JavaFX 2.0 Beta JavaFX 2.0 GA (General Availability) Copyright 2010 Oracle JavaFX Beta in Late May!

78. Pro JavaFX 2 Platform Coming Soon! Coming 2nd half of this year All examples rewritten in Java Will cover the new JavaFX 2.0 APIs 76

79. 77 Stephen Chin steveonjava@gmail.com tweet: @steveonjava