web.xml is quite perplexing 1

[plasante]

I'm running Apache Tomcat/4.1.30 on Windows XP and I have the following problem:

This web.xml works fine:

<web-app>
<servlet>
<servlet-name>myServlet</servlet-name>
<servlet-class>HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>myServlet</servlet-name>
<url-pattern>/HelloWorld</url-pattern>
</servlet-mapping>
</web-app>

This one also works fine:

<web-app>
<description>MySQL Test App</description>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/TestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>

But this one generates an error when I start Tomcat:

<web-app>
<description>MySQL Test App</description>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/TestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
<servlet>
<servlet-name>myServlet</servlet-name>
<servlet-class>HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>myServlet</servlet-name>
<url-pattern>/HelloWorld</url-pattern>
</servlet-mapping>
</web-app>

Here is the error:

1-Aug-2004 8:02:28 PM org.apache.commons.digester.Digester error
SEVERE: Parse Error at line 23 column 11: The content of element type "web-app"
must match "(icon?,display-name?,description?,distributable?,context-param*,filt
er*,filter-mapping*,listener*,servlet*,servlet-mapping*,session-config?,mime-map
ping*,welcome-file-list?,error-page*,taglib*,resource-env-ref*,resource-ref*,sec
urity-constraint*,login-config?,security-role*,env-entry*,ejb-ref*,ejb-local-ref
*)".

Any suggestion as to what is causing the problem?

 

[byam]

According to DTD for web.xml,

<!ELEMENT web-app 
(icon?, display-name?, description?, distributable?,
context-param*, filter*, filter-mapping*, listener*, [COLOR=red]servlet*[/color], [COLOR=red]servlet-mapping*[/color], session-config?, mime-mapping*, welcome-file-list?, error-page*, taglib*, resource-env-ref*, [COLOR=red]resource-ref*[/color], security-constraint*, login-config?, security-role*, env-entry*, ejb-ref*,  ejb-local-ref*)>

sequence of element does matter and

<servlet> should goes before
<servlet-mapping> which should goes before
<resource-ref>

The problem of your later config is that the order of the elements are violating the dtd, which is the error complaining about.

 

[plasante]

GeeWhizz. Thanks. It has solved my problem.
Here is my new web.xml

<web-app>

<description>MySQL Test App</description>

<servlet>
<servlet-name>myServlet</servlet-name>
<servlet-class>HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>myServlet</servlet-name>
<url-pattern>/HelloWorld</url-pattern>
</servlet-mapping>

<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/TestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

</web-app>

I can stop pulling my hair off now