Spring application context showing how to reference JNDI resources exposed by a container

gistfile1.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jee="http://www.springframework.org/schema/jee"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
                  http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd">

    <!-- see https://gist.github.com/prule/5523793 for an example tomcat configuration exposing these JNDI resources -->

    <context:property-placeholder order="1" ignore-unresolvable="true" system-properties-mode="OVERRIDE"/>

    <bean id="envConfig" class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
        <!-- load properties bundled with the application -->
        <property name="locations">
            <list>
                <value>classpath:app.properties</value>
            </list>
        </property>
        <!-- add JNDI based properties exposed by the container -->
        <property name="properties">
            <bean class="java.util.Properties">
                <constructor-arg>
                    <map>
                        <entry key="ldap.host">
                            <jee:jndi-lookup jndi-name="java:comp/env/ldap/host"/>
                        </entry>
                    </map>
                </constructor-arg>
            </bean>
        </property>
    </bean>

    <!-- use the String exposed by JNDI -->
    <bean id="contextSource"
          class="org.springframework.security.ldap.DefaultSpringSecurityContextSource">
        <constructor-arg value="ldap://${ldap.host}/ou=users,dc=javathinking,dc=com"/>
        <property name="userDn" value="uid=admin,ou=system"/>
        <property name="password" value="secret"/>
    </bean>

    <!-- use the DataSource exposed by JNDI -->
    <bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName" value="java:comp/env/jdbc/mydb"/>
    </bean>

    <!-- use the mail Session exposed by JNDI -->
    <bean id="mailSession" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName" value="java:comp/env/mail/session"/>
    </bean>

</beans>