Programming Tutorials

1. Create a Resourceand a ResourceParams element in server.xml, or in the XML file that you have placed in Tomcat's webapps directory. These elements describe the JNDI object you are creating in order to provide your servlets or JSPs with a DataSource.

2. Add a resource-refelement to web.xml, which allows the components in the associated web application to access the configured DataSource.

Example below shows the Resource and a ResourceParams elements in server.xml. This example describes a DataSource that connects with an Oracle 8i database.

The resource element in server.xml

<Resource name="jdbc/oracle-8i-athletes" scope=
 "Shareable" type="javax.sql.DataSource" auth=
 "Container" description="Home Oracle 8i Personal Edition"/>
 <ResourceParams name="jdbc/oracle-8i-athletes">
 <parameter>
 <name>driverClassName</name>
 <value>oracle.jdbc.driver.OracleDriver</value>
 </parameter>
 <parameter>
 <name>url</name>
 <value>jdbc:oracle:thin:@192.168.0.2:1521:ORCL</value>
 </parameter>
 <parameter>
 <name>username</name>
 <value>scott</value>
 </parameter>
 <parameter>
 <name>password</name>
 <value>tiger</value>
 </parameter>
</ResourceParams>

Create a Resource and ResourceParams element for each database that your application uses. Example below shows the resource-ref element associated with the Resource specified by example above.

A resource-ref element specifies a DataSource in web.xml

<!-- top of web.xml file -->
<resource-ref>
 <res-ref-name>jdbc/oracle-8i-athletes</res-ref-name>
 <res-type>javax.sql.DataSource</res-type>
 <res-auth>Container</res-auth>
</resource-ref>
<!-- rest of web.xml file -->

The JNDI path to this DataSource, which you use in a JNDI lookup (see the next recipe), is jdbc/oracle-8i-athletes.