java servlet 初始化参数

Web.xml
<servlet>
 <servlet-name>sr</servlet-name>
 <servlet-class>wap.searchResult</servlet-class>
 <init-param>
 <param-name>DataSource</param-name>
 <param-value>D:/Tomcat4.1/webapps/webgis/data/410100/</param-value>
 </init-param>
</servlet>

Servlet
String getConfig=getInitParameter("DataSource");