Help me out to specify driver in web.xml

Question

i am new programmer and i dont no where to specify driver in web.xml so that i ll get connection using datasource. i know the code in jsp but i dont no where and how to specify driver and under what tag.
This is few steps which i know
!>jsp side i know what to write ie
Context ctx=new IntialContext();
DataSource ds=(DataSource) ctx.lookup("java:comp/env/jdbc/test");
Connection cn=ds.getConnection("umesh","umesh");
2> what and where to write in web.xml
3> i am going to control panel and in that obdc datasource i am going in system tab
there i am adding oracle and DATASOURCE NAME as "test"
is this will work or i have to write something in web.xml also
thanks in advance
help me out

Answer 1

In addittion to following the steps as indicated by the above URL, make the context entries in the
app_root/META-INF/context.xml file .
As I encountered lots of probelms in settingup the JNDI datasource via server.xml or web.xml file
To be precise , do follwoing:
1. Make META-INF directory and add context.xml file to include following:
<Context path="/app_name" docBase="app_name"
debug="5" reloadable="true" crossContext="true">
<Logger className="org.apache.catalina.logger.FileLogger"
prefix="Test_log." suffix=".txt"
timestamp="true"/>
<Resource name="jdbc/yourDB"
auth="Container"
type="javax.sql.DataSource"/>
<ResourceParams name="jdbc/yourDB">
<parameter>
<name>factory</name>
<value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
</parameter>
<!-- Maximum number of dB connections in pool. Make sure you
configure your mysqld max_connections large enough to handle
all of your db connections. Set to 0 for no limit.
-->
<parameter>
<name>maxActive</name>
<value>100</value>
</parameter>
<!-- Maximum number of idle dB connections to retain in pool.
Set to 0 for no limit.
-->
<parameter>
<name>maxIdle</name>
<value>30</value>
</parameter>
<!-- Maximum time to wait for a dB connection to become available
in ms, in this example 10 seconds. An Exception is thrown if
this timeout is exceeded. Set to -1 to wait indefinitely.
-->
<parameter>
<name>maxWait</name>
<value>10000</value>
</parameter>
<!-- MySQL dB username and password for dB connections -->
<parameter>
<name>username</name>
<value>dbuser</value>
</parameter>
<parameter>
<name>password</name>
<value>dbpwd</value>
</parameter>
<!-- Class name for the official MySQL Connector/J driver -->
<parameter>
<name>driverClassName</name>
<value>com.mysql.jdbc.Driver</value>
</parameter>
<!-- The JDBC connection url for connecting to your MySQL dB.
The autoReconnect=true argument to the url makes sure that the
mm.mysql JDBC Driver will automatically reconnect if mysqld closed the
connection. mysqld by default closes idle connections after 8 hours.
-->
<parameter>
<name>url</name>
<value>jdbc:mysql://localhost:3306/yourDB?autoReconnect=true</value>
</parameter>
</ResourceParams>
</Context>
2. In the web.xml include following:
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<display-name>Hello, World Application</display-name>
<description>
     None </description>
<description>
Resource reference to a factory for java.sql.Connection
instances that may be used for talking to a particular
database that is configured in the server.xml file.
</description>
<resource-ref>
<description> Database </description>
<res-ref-name>jdbc/yourDB</res-ref-name>
<res-ref-type>javax.sql.DataSource</res-ref-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>
Try to make a war file for your application and deploy it using the Tomcat manager application..
Asif