Devoxx 2013 - EJB 3.2 and Beyond

David Blevins

deprecated stuff: (aka. 'optional')

• Entity Beans (CMP & BMP)
• JAX-RPC -> replaced by JAX WS and JAX-RS
  • XML-RPC
  • Soap Encoding

API Groups: EJB spec sliced in groups -- check if your JEE server supports your requirements:

• EJB lite
• MDB
• EJB remote
• persistent Timers
• JAX-WS
• Embeddable EJB Container
• EJB 2.x
• Entity beans

small fixes:

• lifted restriction from EJB: "do not touch the file system" (wasn't enforced)
• business interfaces: allow multiple interface implementation
• interceptors: difficult method signatures -> 1 method can intercept all events
• transactional callbacks: now allowed for @Stateful
• passivation capable (EJB with CDI scopes)
• timer service: more global, usable outside bean code (javax.ejb.Timer & TimerHandle)
• security: implicit '**' role (= allow any authenticated user) and no more xml needed

Bigger fix: Message-Driven Beans (MDB)

• basics: (ongoing!)
  • not specific to JMS! (= Connector-Driven Beans)
  • configuration outdated
    • loosely typed
    • bad documentation
  • static interface (text)
• learning from JAX-RS
  • no interfaces
  • fluid method signatures
  • annotation-based config
    • strongly typed
    • self-documenting
    • targeted (class, method or param)
• api for creating your own connector:
  • implement ResourceAdapter: bean invocation
  • MessageEndPoint
  • annotation in MessageDriven bean: @MessageDriven
  • demo: implementation accessible with telnet: custom command prompt / commands.
  • -> MDB is basis for accessing any legacy system
  • -> can replace JMX; portable / standard
• ref: https://github.com/dblevins/mdb-improvements

future JEE8 (under development):

• CDI-EJB Alignment
• scopes are similar
• fundamentally the same: both return a "fake" Proxy object as interface
• difference is services: EJB has extra security and transaction -> allow EJB services on CDI beans
• life-cycle lineup: @Singleton, @Stateful
• deprecate EJB (will take years...)