OW2 Utilities is a newly accepted project in the consortium. It aims to be the OW2 toolkit catalog for common pieces of code that everybody rewrite for each new project. This presentation will start with a description of the goals of that project, a little bit of history, then we will explain why it's important to maximize re-use within the consortium (reliability, ...). In a second part we will focus to the most useful and/or interesting modules provided by this project. This session will be developer-oriented, with code samples and effective use cases.

1. OW2 UTILITIES
The Swiss Army Knife Of OW2 Projects
Guillaume Sauthier
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 1

2. OW2 Utilities
Because

3. code

4. should

5. be

6. written

7. only

8. once
Because

9. code

10. should

11. be

12. well

13. tested
Because

14. code

15. should

16. be

17. shared
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 2

18. Genesis
How

19. did

20. we

21. get

22. there

23. ?
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 3

24. A LITTLE BIT OF HISTORY
• Was born in 2006 inside the OW2 EasyBeans project
• Used in JOnAS, CAROL, CMI, EasyBeans, Shelbie, JASMINe for years
• Extracted as a separate maven project in 2008
• More than 35 releases up to today !
• Proposed as top level OW2 project in 2012
• We’re here now :)
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 4

25. Modules
15

26. minutes

27. is

28. so

29. short,

30. and

31. we

32. have

33. so

34. many

35. modules
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 5

36. QUITE BASIC STUFF
Just

37. to

38. be

39. mentioned
• I18n and Logger • Simple Java/Xml mapper (read your
Xml configuration files)
• Internationalized loggers, Java 5 style
• Base64
• Xml parsing • Encode, decode
• Obtain a DocumentParser, extract
values from Elements (trimmed, • File/URL conversion
Properties, default values, ...)
• Classloader aware
• Xml Config ObjectInputStream
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 6

40. ANNOTATION PROCESSOR
Want

41. a

42. nice

43. way

44. to

45. visit

46. annotations

47. of

48. an

49. instance

50. ?
• Traverse Class, Method and Field declaration
• Support inheritance
• Call interested AnnotationHandler(s)
public class SampleAnnotationHandler extends AbstractAnnotationHandler {
public boolean isSupported(Class? extends Annotation clazz) {
return clazz.equals(Hello.class);
}
@Override
IAnnotationProcessor processor = new DefaultAnnotationProcessor();
public void process(Annotation annotation, Class? clazz, Object target)
processor.addAnnotationHandler(new SampleAnnotationHandler());
throws ProcessorException {
processor.addAnnotationHandler(/* as many handler as you want */);
System.out.printf(Type %s is annotated with @%s(%s),
processor.process(/* some instance */);
clazz,
annotation.annotationType().getSimpleName()
((Hello) annotation).name());
}
}
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 7

51. Asynchronous
EVENT SYSTEM Support
• On steroid topic notification system // Simple asynchronous listener
IEventListener listener = new IEventListener() {
public void handle(IEvent event) {
• Hierarchical, multi-threaded
// Do your own casting here
System.out.printf(Received Event %s, event);
}
public EventPriority getPriority() {
• Dispatcher fires event on a topic
return EventPriority.ASYNC_HIGH;
}
public boolean accept(IEvent event) { return true; }
};
• Listeners receive events matching a topic pattern
• Declares a priority (SYNC, ASYNC)
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
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52. // Create a Dispatcher
EVENT SYSTEM Some

53. code
EventDispatcher dispatcher = new EventDispatcher();
dispatcher.setNbWorkers(3); // Listen to all Event published in /result/**
dispatcher.start(); eventService.registerListener(listener, /result/.*);
// Topic registration
eventService.registerDispatcher(/result/success, dispatcher);
Dispatchers Loose Coupling Event Listeners
Event Source(s)
Asynchronous
Consumer(s)
/a/b
/a
/c
Event Service
// Dispatch an Event
dispatcher.dispatch(new MyEvent(/result/.*));
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 9

54. Re-using
POOL instances
public static void main(String[] args) throws Exception {
• Simple Pooling API
PoolFactoryPooled, Long poolFactory = new PooledFactory();
JPoolPooled,Long pool = new JPoolPooled, Long(poolFactory);
pool.start();
Pooled one = pool.get();
• Pool size, waiters, timeout
Pooled two = pool.get();
Pooled three = pool.get();
Pooled four = pool.get(); // Will block until timeout or a release
}
•
Thread-safe private static final class PooledFactory implements PoolFactoryPooled, Long {
public Pooled create(Long clue) throws PoolException {
return new Pooled(clue);
}
• Basic implementation
public boolean isMatching(Pooled instance, Long clue) {
}
return instance.id == clue;
public void remove(Pooled instance) { // Destroy instance }
•
public boolean validate(Pooled instance, PoolEntryStatistics stats) {
Synchronous
}
return true;
}
• Advanced implementation @Pool(min = 1, max = 3)
private static class Pooled {
long id;
public Pooled(Long clue) { id = clue; }
•
}
Asynchronous, composable
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 10

55. Variable
SUBSTITUTION processing
• Extract variables declaration from String
• ‘Hello ${speaker.name} !’ DefaultSubstitutionEngine engine = new DefaultSubstitutionEngine();
ChainedResolver chain = new ChainedResolver();
chain.getResolvers().add(new SpeakerResolver());
• PropertyResolvers
chain.getResolvers().add(new DateResolver());engine.setResolver(chain);
engine.substitute(Hello ${speaker.name} ! -- ${date});
public class SpeakerResolver implements IPropertyResolver {
public String resolve(String expression) {
return speaker.name.equals(expression) ? Guillaume : null;
• Provides value for expression
}
}
public class DateResolver implements IPropertyResolver {
public String resolve(String expression) {
• Composable
}
}
return date.equals(expression) ? (new Date()).toString() : null;
• Support recursion (variables in variable)
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 11

56. Resource
ARCHIVE Abstraction
• Uniform API for resource consumption
• Supporting (out of the box) public interface IArchive {
String getName();
URL getURL() throws ArchiveException;
• Directory URL getResource(String resourceName) throws ArchiveException;
IteratorURL getResources() throws ArchiveException;
• Jar IteratorURL getResources(String resourceName) throws ArchiveException;
IteratorString getEntries() throws ArchiveException;
boolean close();
• OSGi Bundle IArchiveMetadata getMetadata();
}
• Extensible
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 12

57. BUNDLES, BUNDLES, BUNDLES
• Around 20 common libraries wrapped as Bundles
• commons-{collections, logging, modeler}, javassist, jaxb2-ri, jgroups, jsch, opencsv,
weld, zookeeper, bouncycastle, ...
• Correct exported packages version, verified imports
• All other modules are OSGi Bundles
• Versioned API, content exported
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 13

58. Contributions
What

59. about

60. you

61. ?
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
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62. ANONYMOUS QUOTES
‘I

63. want

64. to

65. code,

66. where

67. are

68. the

69. repositories

70. ?’
http://gitorious.ow2.org/ow2-utilities
‘You

71. convinced

72. me,

73. let

74. me

75. write

76. some

77. documentation’
http://utilities.ow2.org
‘Wow,

78. they

79. even

80. have

81. a

82. Bamboo

83. for

84. CI’
http://bamboo.ow2.org/browse/UTIL
‘Do

85. they

86. really

87. need

88. a

89. JIRA,

90. it’s

91. working

92. so

93. great

94. !’
http://jira.ow2.org/browse/UTIL
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 15

95. Questions
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
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96. utilities.ow2.org
guillaume.sauthier@peergreen.com
@sauthieg
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
www.ow2.org 17

97. RESOURCES
• http://www.flickr.com/photos/emagic/56206868/
OW2 Annual Conference 2012, 27-29 November, Orange Labs, Paris
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