Title: CDI @RequestScoped
This example show the use of @RequestScoped
annotation for injected objects. An object which is defined as @RequestScoped
is created once for every request and is shared by all the bean that inject it throughout a request.
This example depicts a similar scenario to cdi-application-scope. A restaurant guest orders a soup from the waiter. The order is passed to the chef who prepares it and passes it back the waiter who in turn delivers it to the guest.
The Waiter
session bean receives a request from the test class via the orderSoup()
method. A Soup
insance will be created in this method and will be shared throughout the request with the Chef
bean. The method passes the request to the Chef
bean. It then returns the name of the soup to the test class.
@Stateless public class Waiter { @Inject private Soup soup; @EJB private Chef chef; public String orderSoup(String name){ soup.setName(name); return chef.prepareSoup().getName(); } }
The Soup
class is an injectable POJO, defined as @RequestScoped
. This means that an instance will be created only once for every request and will be shared by all the beans injecting it.
@RequestScoped 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; } }
The Chef
class is a simple session bean with an injected Soup
field. Normally, the soup parameter would be passed as a prepareSoup()
argument, but for the need of this example it's passed by the request context.
@Stateless public class Chef { @Inject private Soup soup; public Soup prepareSoup() { return soup; } }
This is the entry class for this example.
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 soup = joe.orderSoup(TOMATO_SOUP); assertEquals(TOMATO_SOUP, soup); soup = joe.orderSoup(POTATO_SOUP); assertEquals(POTATO_SOUP, soup); } @After public void closeContainer() throws Exception { container.close(); } }
In the output you can see that there were two Soup
instances created - one for each request.
------------------------------------------------------- T E S T S ------------------------------------------------------- Running org.superbiz.cdi.requestscope.RestaurantTest Apache OpenEJB 4.0.0-beta-2-SNAPSHOT build: 20111224-11:09 http://openejb.apache.org/ INFO - openejb.home = C:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope INFO - openejb.base = C:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-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-request-scope\target\classes INFO - Beginning load: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope\target\classes INFO - Configuring enterprise application: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope INFO - Configuring Service(id=Default Managed Container, type=Container, provider-id=Default Managed Container) INFO - Auto-creating a container for bean cdi-request-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 Chef: Container(type=STATELESS, id=Default Stateless Container) INFO - Enterprise application "c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope" loaded. INFO - Assembling app: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope INFO - Jndi(name="java:global/cdi-request-scope/Chef!org.superbiz.cdi.requestscope.Chef") INFO - Jndi(name="java:global/cdi-request-scope/Chef") INFO - Jndi(name="java:global/cdi-request-scope/Waiter!org.superbiz.cdi.requestscope.Waiter") INFO - Jndi(name="java:global/cdi-request-scope/Waiter") INFO - Created Ejb(deployment-id=Chef, ejb-name=Chef, container=Default Stateless Container) INFO - Created Ejb(deployment-id=Waiter, ejb-name=Waiter, container=Default Stateless Container) INFO - Started Ejb(deployment-id=Chef, ejb-name=Chef, 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-request-scope) Soup created Soup created INFO - Undeploying app: c:\Users\Daniel\workspaces\openejb\openejb\examples\cdi-request-scope Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.412 sec Results : Tests run: 1, Failures: 0, Errors: 0, Skipped: 0