CDI @ApplicationScoped
This example show the use of @ApplicationScoped
annotation for injected objects. An object which is defined as @ApplicationScoped
is created once for the duration of the application.
Example
This example depicts a similar scenario to cdi-request-scope. A restaurant guest orders a soup from the waiter. The waiter then delivers the soup back to the guest. Another guest can order the same soup that was ordered by the previous client - this is where the application scope is used.
Waiter
The Waiter
session bean receives a request from the test class via the orderSoup()
method and sets the name for the soup
field. The orderWhatTheOtherGuyHad()
method returns the name of the soup
field.
@Stateless
public class Waiter {
@Inject
public Soup soup;
public String orderSoup(String name){
soup.setName(name);
return soup.getName();
}
public String orderWhatTheOtherGuyHad() {
String name = soup.getName();
return name;
}
}
Soup
The Soup
class is an injectable POJO, defined as @ApplicationScoped
. This means that an instance will be created only once for the duration of the whole application. Try changing the @ApplicationScoped
annotation to @RequestScoped
and see what happens.
@ApplicationScoped
public class Soup {
private String name = "Soup of the day";
@PostConstruct
public void afterCreate() {
System.out.println("Soup created");
}
public String getName() {
return name;
}
public void setName(String name){
this.name = name;
}
}
Test Case
This is the entry class for this example. First a soup is ordered via orderSoup()
method. This initiates the soup
field. Next, orderWhatTheOtherGuyHad()
method returns the soup from the application context.
public class RestaurantTest {
private static String TOMATO_SOUP = "Tomato Soup";
private EJBContainer container;
@EJB
private Waiter joe;
@Before
public void startContainer() throws Exception {
container = EJBContainer.createEJBContainer();
container.getContext().bind("inject", this);
}
@Test
public void orderSoup(){
String someSoup = joe.orderSoup(TOMATO_SOUP);
assertEquals(TOMATO_SOUP, someSoup);
String sameSoup = joe.orderWhatTheOtherGuyHad();
assertEquals(TOMATO_SOUP, sameSoup);
}
@After
public void closeContainer() throws Exception {
container.close();
}
}
Running
In the output you can see that there is just one Soup
instance created - one for the whole application.
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T E S T S
-------------------------------------------------------
Running org.superbiz.cdi.applicationscope.RestaurantTest
Apache OpenEJB 7.0.0-SNAPSHOT build: 20111224-11:09
http://tomee.apache.org/
INFO - openejb.home = C:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope
INFO - openejb.base = C:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope
INFO - Using 'javax.ejb.embeddable.EJBContainer=true'
INFO - Configuring Service(id=Default Security Service, type=SecurityService, provider-id=Default Security Service)
INFO - Configuring Service(id=Default Transaction Manager, type=TransactionManager, provider-id=Default Transaction Manager)
INFO - Found EjbModule in classpath: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope\target\classes
INFO - Beginning load: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope\target\classes
INFO - Configuring enterprise application: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope
INFO - Configuring Service(id=Default Managed Container, type=Container, provider-id=Default Managed Container)
INFO - Auto-creating a container for bean cdi-application-scope.Comp: Container(type=MANAGED, id=Default Managed Container)
INFO - Configuring Service(id=Default Stateless Container, type=Container, provider-id=Default Stateless Container)
INFO - Auto-creating a container for bean Waiter: Container(type=STATELESS, id=Default Stateless Container)
INFO - Enterprise application "c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope" loaded.
INFO - Assembling app: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope
INFO - Jndi(name="java:global/cdi-application-scope/Waiter!org.superbiz.cdi.applicationscope.Waiter")
INFO - Jndi(name="java:global/cdi-application-scope/Waiter")
INFO - Created Ejb(deployment-id=Waiter, ejb-name=Waiter, container=Default Stateless Container)
INFO - Started Ejb(deployment-id=Waiter, ejb-name=Waiter, container=Default Stateless Container)
INFO - Deployed Application(path=c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope)
Soup created
INFO - Undeploying app: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-application-scope
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.42 sec
Results :
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0