You can use the @Resource annotation to define a reference. The following table lists the types of resources that can be specified in the @Resource annotation.

Table 12-6 Types of resources that can be specified in the @Resource annotation

Types of resources	Specification
javax.sql.DataSource#1	Y
javax.mail.Session	Y
java.net.URL	N
javax.jms.ConnectionFactory	Y
javax.jms.QueueConnectionFactory#2	Y
javax.jms.TopicConnectionFactory	Y
javax.jms.Queue#2	Y
javax.jms.Topic	Y
javax.resource.cci.ConnectionFactory#3	Y
javax.resource.cci.InteractionSpec	N
javax.transaction.UserTransaction	Y#4
org.omg.CORBA_2_3.ORB	Y#5
javax.xml.rpc.Service	N
javax.xml.ws.Service	N
javax.jws.WebService	N
javax.ejb.EJBContext	Y#6
javax.ejb.SessionContext	Y#6
javax.ejb.TimerService	Y#6#7
Resources specific to the JavaBeans resources	Y
java.lang.String	Y#8
java.lang.Character	Y#8
java.lang.Integer	Y#8
java.lang.Boolean	Y#8
java.lang.Double	Y#8
java.lang.Byte	Y#8
java.lang.Short	Y#8
java.lang.Long	Y#8
java.lang.Float	Y#8

Legend:

Y: Can be specified

N: Cannot be specified

#1: DB Connector is applicable.

#2: TP1/Message Queue - Access and Cosminexus RM are applicable.

#3: uCosminexus TP1 Connector is applicable.

#4: Cannot be used with the Enterprise Beans or interceptors operated with the CMT.

#5: The operation is performed assuming that true is specified in the shareable attribute of ORB. Note that the injected ORB objects are the shared instances used even in other components.

#6: Cannot be used with the classes running on the Web container.

#7: Cannot be used with Stateful SessionBean and the interceptors applicable to Stateful SessionBean.

#8: In the <env-entry-value> tag, you cannot set a value that can be acquired with the DI or lookup.