Servlet: Initialization parameters

[Shekhar Tayade]

Hi,
I am running Tomcat 3.1 and as per the documentation I have put the initialization parameters in web.xml in webapps\root\web-inf folder. I still cann't get these parameters using the getInitParameter() method of ServletConfig. I have made sure that the name and case of the parameter I am using is correct. I am using following code in a servlet to access the parameter:
public void init(ServletConfig config ) throws ServletException{
super.init(config);
parameter1 = config.getInitParameter("param1");
........
I always get the value of "parameter1" variable as null.
Any help is highly appreciated.
Thanks!
Shekhar.

[William Brogden]

My first guess is that something about your web.xml file does not agree with the way your servlet is being invoked. If you are not starting the servlet using the name in web.xml then you won't be able to see the init parameters.
What does your web.xml entry for this servlet look like?
Bill

[Shekhar Tayade]

Hi William,
Thanks! I was using the wrong name of the servlet in web.xml. It really helps to talk to somebody when you know there is something obviously wrong but you cann't see it.
Thanks again.
Shekhar.

[Phil Hanna]

By the way, the web.xml deployment descriptor also allows you to provide initialization parameters that are not tied to any particular servlet:
<web-app>
...
<context-param>
<param-name>JDBC.DRIVER</param-name>
<param-value>
org.enhydra.instantdb.jdbc.idbDriver
</param-value>
</context-param>
...
<servlet>
<servlet-name>servlet1</servlet-name>
<servlet-class>servlet1</servlet-class>
</servlet>
<servlet>
<servlet-name>servlet2</servlet-name>
<servlet-class>servlet2</servlet-class>
</servlet>
...
</web-app>
In the example above, you could retrieve the JDBC driver class name in either servlet1 or servlet2 as follows:
ServletContext context = getServletContext();
String className = context.getInitParameter("JDBC.DRIVER");
or in a JSP:
<% String className =
application.getInitParameter("JDBC.DRIVER"); %>

------------------
Phil Hanna
Author of :
JSP: The Complete Reference
Instant Java Servlets