Servlet has initial parameters in order to make connection to JDBC.
Those initial parameters must be retrieved using ServletConfig.getInitParameter(string).
Why not ServletContext.getInitParameter(string)?
What's the difference?
//web.xml
<web-app>
<servlet>
<servlet-name>setup</servlet-name>
<servlet-class>SetupServlet</servlet-class>
<init-param>
<param-name>jdbcDriver</param-name>
<param-value>xxxxxxxxxJDBCDriver</param-value>
</init-param>
<init-param>
<param-name>jdbcURL</param-name>
<param-value> yyyyyyyy </param-value>
</init-param>
<load-on-startup/>
</servlet>
<web-app>
//SetupServlet.java
public class SetupServlet extends HttpServlet {
private DbConnectionPool pool;
public void init(ServletConfig config) throws ServletException{
super.init(config);
ServletContext app = config.getServletContext();
pool = new DbConnectionPool(
//app.getInitParameter("jdbcDriver"), <--wrong
//app.getInitParameter("jdbcURL"));
config.getInitParameter("jdbcDriver"), <--OK.
config.getInitParameter("jdbcURL"));
}