Servlet Context

It is a interface which provides set of method to communicate with servlet container.

For a web application their will be one context.

It is contained with in ServletConfig Object

Get ServletContext Object

Way 1: Using Config

ServletConfig conf = getServletConfig();
ServletContext context = conf.getServletContext();

Way 2: Using context method from GenericServlet class

ServletContext ctx = getServletContext();

Way 3: Using HttpRequest Object

ServletContext ctx = req.getServletContext();

Use of ServletContext:

1) Variable initialized in web.xml: 

<context-param>
        <param-name>test</param-name>
        <param-value>done</param-value>
</context-param>

We can get this parameter value in Servlet as: 

String str = context.getInitParameter("test");

2) We can also set and get attributes using ServletContext.

e.g: Set the value in one servlet and get in another

ServletOne 

ServletContext ctx = getServletContext();
ctx.setAttribute("test","done");

ServletTwo 

ServletContext ctx = getServletContext();
String str = ctx.getAttribute("test");

3) To get RequestDispatcher Object(to transfer the control from one servlet to another servlet\jsp etc)

RequestDispatcher reqDispObj = getServletContext()
	.getRequestDispatcher("/rootpath/home.jsp");