ServletContext is a interface which helps us to communicate with the servlet container. There is only one ServletContext for the entire web application and the components of the web application can share it.

It gives information about the environment. It represents a Servlet's view of the Web Application.Using this interface servlet can access raw input streams to Web Application resources, virtual directory translation, a common mechanism for logging information, and an application scope for binding objects.

The Mapping of the Context init parameters in web.xml as:

<servlet>
    <servlet-name>Mapping</servlet-name>
    <servlet-class>ContextMapping</servlet-class>
</servlet>

<context-param>
    <param-name>Email</param-name>
    <param-value>userEmail@gmail.com</param-value>
</context-param>

We can access the Init parameter in the servlet using ServletContext :

ServletContext context = getServletContext();
pw.println(context.getInitParameter("Email");