The source code of MaintainSession.java:
<![CDATA[
import java.io.* ;
import javax.servlet.* ;
import javax.servlet.http.* ;
import java.util.* ; // for Date
public class MaintainSession extends HttpServlet {
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws IOException,
ServletException {
doGet(request,response) ;
} // doPost
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws IOException,
ServletException {
response.setContentType("text/html") ;
PrintWriter out = response.getWriter() ;
Furniture.doHeader(out,"Maintain a session") ;
out.println("<p>This page is dynamically generated "
+"by a Java servlet") ;
// Get previously created session, or create new session if none exists
HttpSession session = request.getSession() ;
// Get accessCount attribute from session, or null if doesn't exist
Integer accessCount = (Integer)session.getAttribute("accessCount") ;
// Check the session status
if (accessCount == null) { // No accessCount attribute, i.e. session just created?
// Set up the new session
accessCount = new Integer(1) ;
session.setMaxInactiveInterval(60) ;
out.println("<p>Session starts:") ;
}
else {
// Increment the previously existing access count obtained from session
accessCount = new Integer(accessCount.intValue()+1) ;
out.println("<p>Session continues:") ;
}
// Add the atribute to the session
session.setAttribute("accessCount",accessCount) ;
// Finally, display interesting information about the session
int maxInt = session.getMaxInactiveInterval() ;
out.println("<p>Session ID : " + session.getId()) ;
out.println("<br>Creation time : " + new Date(session.getCreationTime())) ;
out.println("<br>Maximum inactive interval : " + maxInt + " seconds") ;
if (accessCount.intValue() > 1) {
out.println("<br>Last access time : " + new Date(session.getLastAccessedTime())) ;
out.println("<br>Number of accesses : " + accessCount) ;
}
Furniture.doFooter(out) ;
} // doGet
} // class
]]>