Assuming you have a "sampleDS" datasource definition inside your tomcat configuration, you can add following lines to your applicationContext.xml
to access the datasource using JNDI.
<jee:jndi-lookup expected-type="javax.sql.DataSource" id="springBeanIdForSampleDS" jndi-name="sampleDS"/>
You have to define the namespace and schema location for jee
prefix using:
xmlns:jee="http://www.springframework.org/schema/jee"
xsi:schemaLocation="http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd"