Finally I have managed to use a datasource in spring. My database is called AKDB, which was created in Oracle Database11gR2. To use this database as a datasource, heres what I have done in my app :
First, I created a jdbc.properties file. In the file I put in the jdbc connection details which I received from my weblogic as follows :
jdbc.driverClassName=oracle.jdbc.xa.client.OracleXADataSource
jdbc.url=jdbc:oracle:thin:@localhost:1521:AKDB
jdbc.username=username
jdbc.password=password
Now in the spring bean definitions file, namely the dispatcher-servlet.xml in my case, I have defined the beans to use these data as :
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
p:location="/WEB-INF/jdbc.properties" />
Here I have the property configurer to read the properties file that I created. This ensures that spring recognises the file as key-value pair, where the key is called placeholders in this context.
<bean id="dataSource" name="loginappdatasource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource"
p:driverClassName="${jdbc.driverClassName}" p:url="${jdbc.url}"
p:username="${jdbc.username}" p:password="${jdbc.password}" />
Here, I am defining the bean called loginappdatasource of type DriverManagerDataSource using the data from the properties file, accessed using the keys/placeholders.
<bean name="loginDaoImpl" class="com.loginapp.dao.impl.LoginDaoImpl">
<property name="dataSource" ref="loginappdatasource"/>
</bean>
Here I am injecting the datasource bean into my Dao class. Here I resorted to the classic setter injection as I am yet to figure out how to use annotations for the same. Once this is done, the datasource property can be used to take connections from as :
Connection connection = dataSource.getConnection();
The rest is classic jdbc stuff now that you have the connection to the database. I have heard that instead of the DriverManagerDataSource, we can use connection pooling thru JNDI. My next mission is to figure that part out 
