<listener>
    <listener-class>config</listener-class>
</listener> 
  <servlet>
<servlet-name>ProcessReg</servlet-name>
<servlet-class>ProcessReg</servlet-class>
<init-param>
    <param-name>text</param-name>
    <param-value>HelloWorld1</param-value>
</init-param>
public class config implements ServletContextListener {
@Override
public void contextInitialized(ServletContextEvent event) {
    ServletContext servletContext = event.getServletContext();
    String text1 = servletContext.getInitParameter("text");
In method  contextInitialized(ServletContextEvent event) , If There would be two servlets , for example , Let's say name of the second  servlet be Servlet2 and it  let's  say  has also has init - param called text with value HelloWorld2 .
How does listener   know to take ProcessReg servlet ? 
How to get param from Servlet2 ??