CounterServlet.java
import java.io.*; import javax.servlet.*; import javax.servlet.http.*; public class CounterServlet extends HttpServlet{ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(true); response.setContentType("text/html"); PrintWriter out = response.getWriter(); Integer count = new Integer(0); String head; if (session.isNew()) { head = "This is the New Session"; } else { head = "This is the old Session"; Integer oldcount =(Integer)session.getValue("count"); if (oldcount != null) { count = new Integer(oldcount.intValue() + 1); } } session.putValue("count", count); out.println("<HTML><BODY BGCOLOR="#FDF5E6">n" + "<H2 ALIGN="CENTER">" + head + "</H2>n" + "<TABLE BORDER=1 ALIGN=CENTER>n" + "<TR BGCOLOR="#FFAD00">n" +" <TH>Information Type<TH>Session Countn" +"<TR>n" +" <TD>Total Session Accessesn" + "<TD>" + count + "n" + "</TABLE>n" +"</BODY></HTML>" ); } }
Mapping of Servlet (“CounterServlet.java”) in web.xml file
<servlet> <servlet-name>CounterServlet</servlet-name> <servlet-class>CounterServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>CounterServlet</servlet-name> <url-pattern>/CounterServlet</url-pattern> </servlet-mapping>
Running the servlet by this url:
http://localhost:8080/CounterServlet
displays the figure below:
When servlet is hit six times by the user the counter value will be increased by six as shown in figure below:
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