Explain JSP session tracking with example.

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 In JSP, session is an implicit object of type HttpSession. The Java developer can use this object to set,get or remove attribute or to get session information. By default, JSPs have session tracking enabled and a new HttpSession object is instantiated for each new client automatically. Disabling session tracking requires explicitly turning it off by setting the page directive session attribute to false as follows:

<%@ page session="false" %>

Example

//index.html File

<html>

<body>

<form action="welcome.jsp">

<input type="text" name="uname">

<input type="submit" value="go"><br/>

</form>

</body>

</html>

// welcome.jsp File

<html>

<body>

<%

String name=request.getParameter("uname");

out.print("Welcome "+name);

session.setAttribute("user", name);

%>

<a href="second.jsp">second jsp page</a>

</body>

</html>

//second.jsp File

<html>

<body>

<%

String name=( (String) session.getAttribute("user"); out.print("Hello "+name);

%>

</body>

</html>

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