What's New in CDI 2.0 at JUG HH

What's New in CDI 2.0 at JUG HH

Slides to the talk I gave at JUG Hamburg.

Code: https://github.com/mp911de/cdi-2.0

C5f6e8dffbb19acf405198c8fb917337?s=128

Mark Paluch

November 08, 2018
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Transcript

  1. What's New in CDI 2.0 JSR 365 Mark Paluch •

    @mp911de
  2. Mark Paluch @mp911de ‣Software Craftsman ‣Spring Data Engineer @ Pivotal

    ‣EG for CDI 2.0 (JSR365)
  3. CDI Timeline Dec 2009 CDI 1.0 (Java EE 6) Jun

    2013 CDI 1.1 (Java EE 7) Apr 2014 CDI 1.2 (M R) Sep 2014 CDI 2.0 (Kickoff) May 2017 CDI 2.0 (Release) Jul 2018 CDI 2.0 SP1 (Bugfix)
  4. CanDI

  5. Road towards JavaEE 8 • Java 8 baseline • Spec

    split: Core/SE/EE CDI Specification CDI Core CDI for Java SE CDI for Java EE
  6. JavaEE 8 Implementations • IBM OpenLiberty 18 • GlassFish 5

    • WildFly 14
  7. None
  8. Events

  9. @Observes

  10. @ObservesAsync

  11. Asynchronous Events • Notify event observers asynchronously • One or

    more different threads • Decoupled from synchronous events
  12. Firing Async Events @Inject
 private Event<MyEventPayload> event;
 public void triggerEvent()

    {
 event.fireAsync(new MyEventPayload());
 }
  13. Firing Async Events @Inject
 private Event<MyEventPayload> event;
 public void triggerEvent()

    {
 event.fireAsync(new MyEventPayload());
 }
  14. Observing Async Events public void observer(@ObservesAsync MyEvent payload) {
 System.out.println("Yay,

    I'm called async!");
 }
  15. How it works @Observes @ObservesAsync event.fire(…) Sync call Not notified

    event.fireAsync(…) Not notified Async call
  16. Asynchronous Events • Exceptions and Synchronization with CompletionStage • Active

    scopes: Request, Application • Custom scopes depend on the implementation
  17. @Priority

  18. Ordered Events • Add @Priority to event observers • Aids

    observer ordering • Total global order determined when the event is fired
  19. Observer Ordering public void observer(@Observes @Priority(2500) MyEvent event) {
 System.out.println("Default

    priority");
 }
  20. public void earlier(@Observes @Priority(2499) MyEvent event) {
 // yay! I'm

    first
 System.out.println("Notified before all other observers");
 }
 public void observer(@Observes MyEvent event) {
 System.out.println("Default priority");
 } public void later(@Observes @Priority(2501) MyEvent event) {
 System.out.println("Notified after all other observers");
 }
  21. public void earlier(@Observes @Priority(2499) MyEvent event) {
 // yay! I'm

    first
 System.out.println("Notified before all other observers");
 }
 public void observer(@Observes MyEvent event) {
 System.out.println("Default priority");
 } public void later(@Observes @Priority(2501) MyEvent event) {
 System.out.println("Notified after all other observers");
 }
  22. public void earlier(@Observes @Priority(2499) MyEvent event) {
 // yay! I'm

    first
 System.out.println("Notified before all other observers");
 }
 public void observer(@Observes MyEvent event) {
 System.out.println("Default priority");
 } public void later(@Observes @Priority(2501) MyEvent event) {
 System.out.println("Notified after all other observers");
 }
  23. public void earlier(@Observes @Priority(2499) MyEvent event) {
 // yay! I'm

    first
 System.out.println("Notified before all other observers");
 }
 public void observer(@Observes MyEvent event) {
 System.out.println("Default priority");
 } public void later(@Observes @Priority(2501) MyEvent event) {
 System.out.println("Notified after all other observers");
 }
  24. Java SE

  25. Java SE • Currently: Implementation-specific in Weld/ OpenWebBean • Spec

    Goal: Bootstrap API
  26. SeContainerInitializer initializer = SeContainerInitializer .newInstance()
 .disableDiscovery()
 .addBeanClasses(MyApp.class)
 .addPackages(MyOtherServices.class)
 .addExtensions(MyExtension.class);
 


    try (SeContainer container = initializer.initialize()) {
 
 MyApp service = container.select(MyService.class).get();
 service.runMyApplication();
 }
  27. SeContainerInitializer initializer = SeContainerInitializer .newInstance()
 .disableDiscovery()
 .addBeanClasses(MyApp.class)
 .addPackages(MyOtherServices.class)
 .addExtensions(MyExtension.class);
 


    try (SeContainer container = initializer.initialize()) {
 
 MyApp service = container.select(MyService.class).get();
 service.runMyApplication();
 }
  28. SeContainerInitializer initializer = SeContainerInitializer .newInstance()
 .disableDiscovery()
 .addBeanClasses(MyApp.class)
 .addPackages(MyOtherServices.class)
 .addExtensions(MyExtension.class);
 


    try (SeContainer container = initializer.initialize()) {
 
 MyApp service = container.select(MyService.class).get();
 service.runMyApplication();
 }
  29. Portable Extensions

  30. SPI

  31. CDI Extensions • http://www.cdi-spec.org/ ecosystem/

  32. Meta-Data Builder API • Standardized API • CDI 1.0+: Very

    verbose to create • AnnotatedTypes, Beans, BeanAttributes, InjectionPoints, and ObserverMethods • Builder and Configurator-style
  33. public class MyExtension {
 public void afterBeanDiscovery( @Observes AfterBeanDiscovery event)

    {
 event.addBean() .beanClass(MyService.class) .scope(RequestScoped.class) .name("myservice"); } } Add a Bean
  34. public class MyExtension {
 public void afterBeanDiscovery( @Observes AfterBeanDiscovery event)

    {
 event.addBean() .beanClass(MyService.class) .scope(RequestScoped.class) .name("myservice"); } } Add a Bean
  35. public class MyExtension {
 public <T> void processAnnotatedType(@Observes @WithAnnotations(UseCase.class) ProcessAnnotatedType<T>

    pat) {
 
 pat.configureAnnotatedType() .methods() 
 .forEach(m -> m.add(CacheableLiteral.INSTANCE));
 } } Add annotation to Methods
  36. public class MyExtension {
 public <T> void processAnnotatedType(@Observes @WithAnnotations(UseCase.class) ProcessAnnotatedType<T>

    pat) {
 
 pat.configureAnnotatedType() .methods() 
 .forEach(m -> m.add(CacheableLiteral.INSTANCE));
 } } Add annotation to Methods
  37. AOP on produced Bean • CDI 1.0+: Interceptor applied to

    producer method • InterceptionFactory a possible answer @Produces 
 @Transactional
 public MyService produceService() {
 ... 
 }
  38. AOP on produced Bean @Produces
 @RequestScoped
 public MyService createTransactional(InterceptionFactory<MyService> ipf)

    {
 
 ipf.configure()
 .filterMethods(m -> m.getJavaMember().getName().equals("save"))
 .findFirst()
 .ifPresent(m -> m.add(new AnnotationLiteral<Transactional>() {}));
 
 return ipf.createInterceptedInstance(new MyService());
 }
  39. AOP on produced Bean @Produces
 @RequestScoped
 public MyService createTransactional(InterceptionFactory<MyService> ipf)

    {
 
 ipf.configure()
 .filterMethods(m -> m.getJavaMember().getName().equals("save"))
 .findFirst()
 .ifPresent(m -> m.add(new AnnotationLiteral<Transactional>() {}));
 
 return ipf.createInterceptedInstance(new MyService());
 }
  40. Proxy matters

  41. Proxy injection @Inject
 private MyService myService; This is a proxy

    instance
  42. Proxy injection

  43. Proxy injection

  44. Proxy injection @Inject @Named("myBean")
 private ConcurrentHashMap<String, String> myService; /** Implementation

    for put and putIfAbsent */
 final V putVal(K key, V value, boolean onlyIfAbsent)
  45. Normal-scoped beans • Must be proxyable • accessible, no-args constructor

    • non-final classes • accessible, non-final instance methods
  46. Enabling proxying @Produces
 @RequestScoped
 public MyService createTransactional(InterceptionFactory<MyService> factory) {
 


    factory.ignoreFinalMethods(); 
 return factory.createInterceptedInstance(new MyService());
 }
  47. Enabling proxying @Produces
 @RequestScoped
 public MyService createTransactional(InterceptionFactory<MyService> factory) {
 


    factory.ignoreFinalMethods(); 
 return factory.createInterceptedInstance(new MyService());
 }
  48. Get in touch Web: cdi-spec.org Mailing list: cdi-dev@lists.jboss.org IRC: irc://freenode.net/#cdi-dev

    Twitter: @cdispec // @mp911de Github: github.com/cdi-spec CDI 2.0 JCP page: jcp.org/en/jsr/summary?id=365