How to configure a datasource in Apache Tomcat

I have to build a POC (proof of concept) using JDK6, Spring, Hibernate and Apache CXF on Apache Tomcat. I will be using Maven build tool and Nexus repository. My IDE is Eclipse with m2eclipse and spring IDE plugin. In a nutshell we need a webservice application and I have chosen these technologies to develop the solution. I thought it would be a good idea if I blog on how I developed this POC. I will do step-by-step development.

Lets start with "How to configure a datasource in Apache Tomcat".

There is another way of configuring datasource in Tomcat, but I prefer this solution as the configuration resides in the application war file. Simply copy your war file in a tomcat server along with the required jdbc jar and your application is up and running. I wish I can bundle the jdbc jar also in war but unfortunately it doesn't work.

Create a file name "context.xml" (any other name will not work) in META-INF directory of your war file. The content of the context.xml will look like this -

<Context path="/travel" debug="5" reloadable="true" crossContext="true">
  <Resource name="jdbc/travel" auth="Container" type="javax.sql.DataSource"
               maxActive="100" maxIdle="30" maxWait="10000"
               username="user" password="password" driverClassName="com.mysql.jdbc.Driver"
               url="jdbc:mysql://localhost:3306/travel?autoReconnect=true"/>
</Context>

Add this in the web.xml of your war -

<resource-ref>
  <description>Datasource</description>
  <res-ref-name>jdbc/travel</res-ref-name>
  <res-type>javax.sql.DataSource</res-type>
  <res-auth>Container</res-auth>
</resource-ref>

The res-ref-name should match the //Resource@name defined in the context.xml

Copy the required jdbc driver jar in $TOMCAT_HOME/lib directory. In this case its mysql-connector-java-5.1.6.jar for mysql database.