The document outlines new features in Enterprise JavaBean (EJB) 3.1 technology, including ease of use improvements like optional local business interfaces and simplified packaging. It also describes new functionality like singleton session beans, startup and shutdown callbacks, automatic timer creation, and asynchronous session bean invocations. The changes aim to continue focusing on ease of use while adding useful new capabilities to the EJB specification.

1. <Insert Picture Here>
What's New in Enterprise JavaBean Technology
Arun Gupta, Java EE & GlassFish Guy
blogs.sun.com/arungupta, @arungupta

2. Beijing 2010
December 13–16, 2010
2

3. The following is intended to outline our general
product direction. It is intended for information
purposes only, and may not be incorporated into any
contract. It is not a commitment to deliver any
material, code, or functionality, and should not be
relied upon in making purchasing decisions.
The development, release, and timing of any
features or functionality described for Oracle’s
products remains at the sole discretion of Oracle.
3

4. Agenda
• Introduction <Insert Picture Here>
• Ease of Use Improvements
• New Functionality
4

5. EJB 3.1 Specification
• Goals
– Continued focus on ease-of-use
– New features
• JSR (Java Specification Request) 318
– Expert Group Formed – August 2007
– Public Draft – October 2008
– Proposed Final Draft – March 2009
– Final Specification – December 2009
5

6. Ease of Use Improvements
• Optional Local Business Interfaces
• Simplified Packaging
• EJB 3.1 “Lite” API
• Portable Global JNDI Names
• Simple Component Testing
6

7. Session Bean
With “No-interface” View
@Stateless
public class HelloBean {
public String sayHello(String msg) {
return “Hello “ + msg;
}
}
7

8. No-interface View Client
@EJB HelloBean h;
...
h.sayHello(“bob”);
8

9. TM
Java EE Platform 5 Packaging
foo.ear foo.ear
lib/foo_common.jar
foo_web.war
WEB-INF/web.xml com/acme/Foo.class
WEB-INF/classes/
com/acme/FooServlet.class foo_web.war
WEB-INF/classes OR WEB-INF/web.xml
com/acme/Foo.class WEB-INF/classes/
foo_ejb.jar com/acme/FooServlet.class
com/acme/FooBean.class foo_ejb.jar
com/acme/Foo.class com/acme/FooBean.class
9

10. Simplified Packaging
foo.war
WEB-INF/classes/com/acme/
FooServlet.class
FooBean.class
10

11. EJB 3.1 “Lite”
11

12. Portable EJB JNDI Names
Each session bean gets the following entries :
• Globally unique name
java:global[/<app-name>]/<module-name>/<ejb-
name>
• Unique name within same application
java:app/<module-name>/<ejb-name>
• Unique name within defining module
java:module/<ejb-name>
12

13. Session Bean
@Stateless
public class HelloBean implements Hello {
public String sayHello(String msg) {
return “Hello “ + msg;
}
}
If deployed as hello.jar, JNDI entries are:
java:global/hello/HelloBean
java:app/hello/HelloBean
java:module/HelloBean
13

14. Simple Testing : Session Bean
@Stateless
@Local(Bank.class)
public class BankBean implements Bank {
@PersistenceContext EntityManager accountDB;
public String createAccount(AcctDetails d)
{ … }
public void removeAccount(String acctID)
{ … }
14

15. Embeddable API
public class BankTester {
public static void main(String[] args) {
EJBContainer container =
EJBContainer.createEJBContainer();
// Acquire Local EJB reference
Bank bank = (Bank) container.getContext().
lookup(“java:global/bank/BankBean”);
testAccountCreation(bank);
container.close();
15

16. Test Client Execution
% java -classpath bankClient.jar :
bank.jar :
javaee.jar :
<vendor_rt>.jar
com.acme.BankTester
16

17. New Features
• Singletons
• Startup / Shutdown callbacks
• Automatic timer creation
– Cron-like syntax
• Asynchronous session bean invocations
17

18. Singleton
@Singleton
public class SharedBean {
private SharedData shared;
@PostConstruct
private void init() {
shared = ...;
}
public int getXYZ() {
return shared.xyz;
}
18

19. Singleton Concurrency Options
• Single threaded (default)
– For consistency with all existing bean types
• Container Managed Concurrency
– Control access via method-level locking metadata
• Bean Managed Concurrency
– All concurrent invocations have access to bean instance
19

20. Startup / Shutdown Callbacks
@Singleton
@Startup
public class StartupBean {
@PostConstruct
private void onStartup() { … }
@PreDestroy
private void onShutdown() { … }
}
20

21. Timers
• Automatically created EJB Timers
• Calendar-based Timers – cron like semantics
– Every Mon & Wed midnight
@Schedule(dayOfWeek=”Mon,Wed”)
– 2pm on Last Thur of Nov of every year
(hour=”14”, dayOfMonth=”Last Thu”,
month=”Nov”)
– Every 5 minutes of every hour
(minute=”*/5”, hour=”*”)
– Every 10 seconds starting at 30
(second=”30/10”)
– Every 14th minute within the hour, for the hours 1 and 2 am
(minute=”*/14”, hour=”1,2”)
21

22. Automatic Timer Creation
@Stateless
public class BankBean {
@PersistenceContext EntityManager accountDB;
@Resource javax.mail.Session mailSession;
// Callback the last day of each month at 8 a.m.
@Schedule(hour=”8”, dayOfMonth=”Last”)
void sendMonthlyBankStatements() {
...
}
}
22

23. Asynchronous Session Beans
• Control returns to the client before the container
dispatches invocation to a bean instance
• @Asynchronous – method or class
• Return type – void or Future<V>
• “Fire and and Forget” or async results via
Future<V>
• Best effort delivery – persistent delivery
guarantees are not required by spec
• Transaction context does not propagate
– REQUIRED → REQUIRED_NEW
• Security principal propagates
23

24. Asynchronous Session Beans
Code Sample
@Stateless
@Asynchronous
public class SimpleAsyncEJB {
public Future<Integer> addNumbers(int n1, int n2) {
Integer result;
result = n1 + n2;
try {
// simulate JPA queries + reading file system
Thread.currentThread().sleep(2000);
} catch (InterruptedException ex) {
ex.printStackTrace();
}
return new AsyncResult(result);
}
}
http://blogs.sun.com/arungupta/entry/totd_137_asynchronous_ejb_a
24

25. References
• glassfish.org
• blogs.sun.com/theaquarium
• youtube.com/user/GlassFishVideos
• facebook.com/glassfish
• Follow @glassfish
25

26. <Insert Picture Here>
What's New in Enterprise JavaBean Technology
Arun Gupta, Java EE & GlassFish Guy
blogs.sun.com/arungupta, @arungupta