Le temps est révolu où Java EE ne serait qu’à développer des applications de mise à jour de données, avec JSF / EJB / JPA. Aujourd’hui Java EE s’est assoupli et s’est ouvert sur le monde, avec CDI comme clé de voûte et a repoussé nos limites grâce à des capacités d’extension puissantes et faciles d’utilisation comme JCA. Dans un premier temps, nous reviendrons rapidement sur la place de CDI dans JavaEE 7 et sur ses mécanismes d’extension. Dans un deuxième temps, nous verrons les techniques de connecteurs JCA et comment ils peuvent aussi constituer une possibilité d’ouverture simple à mettre en œuvre. JCA fournit des techniques pour gérer des connexions sortantes ou entrantes, sur des formats ou protocoles variés.

1. Avec JavaEE,
fais ce que tu veux…
Alexis Hassler

2. Alexis Hassler
• Développeur, formateur Java
• Indépendant
• Co-leader du
• @AlexisHassler

3. Java EE 1° partie
http://www.public-domain-image.com/

4. Java EE
CDI
JSF
EJB 3
JPA
JAX-RS
WebSocket

5. CDI
JCA

6. MQTT
Broker
Consumer
Consumer
Consumer
Producer
Producer
Producer
Topic
Topic
Topic
Topic
Publish Subscribe

7. MQTT
http://www.galuzzi.it/

8. MQTT
http://commons.wikimedia.org/wiki/File:St_Jude_Medical_pacemaker_with_ruler.jpg

9. MQTT

10. JCA2° partie
http://www.public-domain-image.com/

11. Java
Connector
Architecture

12. Connector Java EE
Java EE
App EIS

13. Outbound

14. Java EE
Connector
App EIS

15. Java EE
App
DataSource

16. Resource
public class SomeNiceBean {
@Resource(name="jdbc/SomeDS")
DataSource dataSource;
public void doTheJob() {
Connection connection = dataSource.getConnection();
...
}
}

17. MQTT Connection Factory
public class SomeNiceBean {
@Resource(name="mqtt/QuestionCF")
ConnectionFactory connectionFactory;
public void doTheJob() {
connectionFactory.getConnection()
.publish(message);
}
}

18. Resource Adapter
Connection ManagedConnection
API Implementation
ManagedConnection
Factory
ConnectionFactory

19. ManagedConnection
Factory
ConnectionFactory
new
ManagedConnection
new
ConnectionManager
Connection
ResourceAdapter
new
ConnectionEvent
Listener XAResource
LocalTransaction
ManagedConnection
MetaData

20. Inbound

21. Java EE
App
Connector
EIS

22. Message Driven Bean
Java EE
MDB
JMS
Destination
Connector

23. JMS Message Driven Bean
@MessageDriven(activationConfig = {
@ActivationConfigProperty(propertyName="destinationLookup",
propertyValue="swt/Question"),
@ActivationConfigProperty(propertyName="destinationType",
propertyValue="javax.jms.Queue"),
})
public class MyJmsBean implements MessageListener {
@Override
public void onMessage(Message message) {
...
}
}

24. MQTT Message Driven Bean
@MessageDriven(
activationConfig = {
@ActivationConfigProperty(propertyName = "topicName",
propertyValue = "swt/Question")
}
)
public class MyMqttBean implements MqttListener {
@Override
public void onMessage(Message message) {
...
}
}

25. ActivationSpec
API Implementation
Message
Listener ResourceAdapter
BootstrapContext
WorkerManager
XAResource

26. Connector API
public interface MqttListener {
void onMessage(Message message);
}
public class Message {
private byte[] payload;
public Message(byte[] payload) {
this.payload = payload;
}
// + Getter
}

27. Message Driven Bean ++
@MessageDriven
public class MyMqttBean implements MqttListener {
@TopicName("swt/Question")
public void onQuestion(Message message) {
...
}
@TopicName("swt/Answer")
public void onAnswer(Message message) {
...
}
}

28. Connector
mqtt-ra.rar
Application
(w. MDB)
mqtt-ra-example.war
WildFly
MQTT
Broker
(mosquitto)
MQTT Client
mosquitto
pub/sub

29. C D I 3° partie
http://www.picturesdepot.com/

30. Context & Dependency Injection
• IoC pour Java EE et Java SE
• Gestion des contextes
• Liant pour la plupart des spec Java EE
• Moteur d’extensions pour Java EE

31. http://commons.wikimedia.org/
Bean

32. @Inject

33. Dependency Injection
public class MessageService {
@Override
public String message() {
return "Bonjour le monde !";
}
}

34. Dependency Injection
public class HelloBean {
@Inject MessageService service;
public void displayHello() {
display( frService.message() );
}
}

35. Highlander Rule
there can be
only one
http://pixabay.com/

36. Qualifiers
public class FrenchMessageService
implements MessageService {
public String message() {
return "Bonjour le monde !";
}
}
public class EnglishMessageService
implements MessageService {
public String message() {
return "Hello World!";
}
}

37. Qualifiers
@Qualifier
@Retention(RUNTIME)
@Target({FIELD, TYPE, METHOD, PARAMETER})
public @interface French {}
@Qualifier
@Retention(RUNTIME)
@Target({FIELD, TYPE, METHOD, PARAMETER})
public @interface English {}

38. Qualifiers
@French
public class FrenchMessageService
implements MessageService {
public String message() {
return "Bonjour le monde !";
}
}
@English
public class EnglishMessageService
implements MessageService {
public String message() {
return "Hello World!";
}
}

39. Qualifiers
public class HelloBean {
@Inject @French MessageService service;
public void displayHello() {
display(service.message());
}
}

40. Programmatic
Lookup
http://pixabay.com/

41. Programmatic lookup
public class HelloBean {
@Inject Instance<MessageService> service;
public void displayHello() {
if (! service.isUnsatisfied()) {
display(service.get().message());
}
}
}

42. Programmatic lookup
public class HelloBean {
@Inject @Any
Instance<MessageService> services;
public void displayHello() {
for (MessageService service : services) {
display(service.message());
}
}
}

43. Contexts
@Dependent
@RequestScoped
@ConversationScoped
@SessionScoped
@ApplicationScoped
public class MessageService {
...
}

44. Decorators
@Decorator
@Priority(Interceptor.Priority.APPLICATION)
public class MessageDecorator
implements MessageService {
@Inject @Delegate @Any MessageService service;
public String message() {
return service.message() + " -decorated";
}
}
http://pixabay.com/

45. Interceptors
http://commons.wikimedia.org/

46. Interceptors
@InterceptorBinding
@Target({METHOD, TYPE})
@Retention(RUNTIME)
public @interface Loggable {}

47. @Interceptor @ILnoggtabeler ceptors
public class LogInterceptor {
@AroundInvoke
public Object log(InvocationContext ic)
throws Exception {
System.out.println("Entering "
+ ic.getMethod().getName());
try {
return ic.proceed();
} finally {
System.out.println("Exiting "
+ ic.getMethod().getName());
}
}
}

48. Interceptors
@Loggable
public class HelloBean {
@Inject MessageService service;
public void displayHello() {
display(service.message());
}
}

49. Producers
http://commons.wikimedia.org/

50. Producers
public class FacesProducer {
@Produces @RequestScoped
public FacesContext produceFacesContext() {
return FacesContext.getCurrentInstance();
}
}

51. Producers
@Produces
public Logger produceLogger(
InjectionPoint injectionPoint) {
String loggerName = injectionPoint
.getMember()
.getDeclaringClass()
.getName();
return Logger.getLogger(loggerName);
}

52. public class HelloBean {
@Inject MessageService service;
@Inject Event<Message> messageEvent;
public void displayHello() {
display(service.message());
messageEvent.fire(
new Message(frService.message()));
}
}
Events

53. Events
public class MessageReceiver {
public void receive(@Observes Message message) {
System.out.println("Received: " + message.text);
}
}

54. Synthèse
Decoration Interception Event JavaEE
Injection Context
Integration
Portable Extension

55. CDI
Portable Extensions

56. Bean Manager
https://www.kingbean.com/

57. Bean Manager
• Interagir avec le conteneur CDI
• Lecture seule
• Injectable
• JNDI
• java:comp/BeanManager
public class HelloBean {
@Inject BeanManager beanManager;
...
}

58. Extension
• Manipuler les métadonnées du container
• AnnotatedType
• InjectionPoint / InjectionTarget
• BeanAttributes / Beans
• Producer, Observer
• Pendant le démarrage

59. Comment ?
En observant les
événements
déclenchés par le
conteneur CDI

60. Exemple (-)
• Exclure les entités JPA
public class VetoEntityExtension
implements Extension {
public void vetoEntity(
@Observes @WithAnnotations({Entity.class})
ProcessAnnotatedType<?> pat) {
pat.veto();
}
}

61. Exemple (+)
• Ajouter un bean
public class HashMapAsBeanExtension
implements Extension {
public void addHashMapAsAnnotatedType(
@Observes BeforeBeanDiscovery bbd,
BeanManager beanManager) {
bbd.addAnnotatedType(
beanManager.createAnnotatedType(HashMap.class)
);
}
}

62. CDI 1.1 Lifecycle
Before Bean
Discovery
Process Bean
Scan
Archive
Process
Annotated
Type
After
Deployment
Validation
Application
Running
Before
Shutdown
Undeploy
Application
After Bean
Discovery
Process
Producer
Process
Injection
Target
Process
Observer
Method
Process
Injection
Point
Process Bean
Attributes
After Type
Discovery
événement unique
événements multiples
étape interne
Deployment
starts
Bean
eligibility
check

63. Application
mqtt-cdi-example.war
WildFly
MQTT
Broker
(mosquitto)
MQTT Client
mosquitto
pub/sub
http://pixabay.com/

64. 4° partie
JCA // CDI

65. CDI
JCA

66. Managed Connection Factory
@ConnectionDefinition
(connectionFactory = MqttConnectionFactoryImpl.class,
connectionFactoryImpl = MqttConnectionFactoryImpl.class,
connection = BlockingConnection.class,
connectionImpl = BlockingConnection.class)
public class MqttManagedConnectionFactory
implements ManagedConnectionFactory,
ResourceAdapterAssociation, Serializable {
@Inject
ResourceAdapter ra;
}

67. JCA
CDI

68. public class SomeNiceBean {
@Inject
MqttConnectionFactory connectionFactory;
public void doTheJob() {
javax.enterprise.inject.
Connection connection = connectionFactory.getConnection();
...
}
UnsatisfiedResolutionException
}

69. Java EE 8
• Implicit Producers ?
• Ambiguities ?
• Qualifiers ?

70. JCA // CDI

71. JCA
ManagedConnection
Factory
ConnectionFactory
new
ManagedConnection
new
ConnectionManager
Connection
ResourceAdapter
new
ConnectionEvent
Listener
XAResource
LocalTransaction
ManagedConnection
MetaData
WorkerManager

72. CDI
UserTransaction
ManagedExecutor
Service
ConnectionFactory
Producer
ConnectionFactory
new
Connection
LocalTransaction

73. Outbound Connector
JCA < CDI

74. Message Driven Bean
@MqttDriven
public class MyMqttBean {
@TopicName("swt/Question")
public void onQuestion(Message message) {
...
}
@TopicName("swt/Answer")
public void onAnswer(Message message) {
...
}
}

75. Message Observer
@ApplicationScoped
public class MyMqttBean {
public void onQuestion(
@Observes @TopicName(value = "swt/Question")
Message message) {
...
}
public void onAnswer(
@Observes @TopicName("swt/QuestionBis")
Message message) {
...
}
}

76. Threads
https://www.flickr.com/photos/mckaysavage/6491930649/

77. Inbound Connector
JCA > CDI

78. Java EE Application Server
App
CDI
App
CDI
App
CDI
JCA

79. ?
http://pixabay.com/fr/point-d-interrogation-boule-demande-65833/

80. Exemples
• https://github.com/antoinesd/cdi-demo
• https://github.com/sewatech/mqtt-ra/
• https://github.com/hasalex/mqtt-cdi
• http://fr.slideshare.net/sewatech/

81. Version longue
• Part 1 : Intro + CDI
• https://parleys.com/play/536749d1e4b04bb59f502706
• Part 2 : JCA + Synthèse
• https://parleys.com/play/5369f1f9e4b04bb59f502725