How to use JNDI DataSource provided by Tomcat in Spring?

If using Spring's XML schema based configuration, setup in the Spring context like this:

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  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/jee http://www.springframework.org/schema/jee/spring-jee.xsd">
...
<jee:jndi-lookup id="dbDataSource"
   jndi-name="jdbc/DatabaseName"
   expected-type="javax.sql.DataSource" />

Alternatively, setup using simple bean configuration like this:

<bean id="DatabaseName" class="org.springframework.jndi.JndiObjectFactoryBean">
    <property name="jndiName" value="java:comp/env/jdbc/DatabaseName"/>
</bean>

You can declare the JNDI resource in tomcat's server.xml using something like this:

<GlobalNamingResources>
    <Resource name="jdbc/DatabaseName"
              auth="Container"
              type="javax.sql.DataSource"
              username="dbUser"
              password="dbPassword"
              url="jdbc:postgresql://localhost/dbname"
              driverClassName="org.postgresql.Driver"
              initialSize="20"
              maxWaitMillis="15000"
              maxTotal="75"
              maxIdle="20"
              maxAge="7200000"
              testOnBorrow="true"
              validationQuery="select 1"
              />
</GlobalNamingResources>

And reference the JNDI resource from Tomcat's web context.xml like this:

  <ResourceLink name="jdbc/DatabaseName"
   global="jdbc/DatabaseName"
   type="javax.sql.DataSource"/>

Reference documentation:

• Tomcat 8 JNDI Datasource HOW-TO
• Tomcat 8 Context Resource Links Reference
• Spring 4 JEE JNDI Lookup XML Schema Reference
• Spring 4 JndiObjectFactoryBean Javadoc

Edit: This answer has been updated for Tomcat 8 and Spring 4. There have been a few property name changes for Tomcat's default datasource resource pool setup.

With Spring's JavaConfig mechanism, you can do it like so:

@Configuration
public class MainConfig {

    ...

    @Bean
    DataSource dataSource() {
        DataSource dataSource = null;
        JndiTemplate jndi = new JndiTemplate();
        try {
            dataSource = jndi.lookup("java:comp/env/jdbc/yourname", DataSource.class);
        } catch (NamingException e) {
            logger.error("NamingException for java:comp/env/jdbc/yourname", e);
        }
        return dataSource;
    }

}