import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class UpdateStat extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException
{
int number=0;
try {
number=Integer.parseInt(request.getParameter("inputNumber"));
} catch (NumberFormatException e){
}
// Add the number to the Stat in our session as well as to the
// Stat in the context
// Get our session (if one exists) otherwise create one
HttpSession session = request.getSession(true);
Stat mStat=(Stat)session.getAttribute("myStat");
if(mStat==null){
mStat=new Stat();
session.setAttribute("myStat",mStat);
}
mStat.add(number); // Don't need this to be synchronized. Only
// the one session should be accessing this!!
// All servlets share an instance of Stat
ServletContext sc=getServletContext();
Stat sStat=(Stat)sc.getAttribute("sharedStat");
String mSummary=sStat.addAndReport(number); // We need this to be synchronized!!
// Possibly many threads will be looking at this instance!
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("");
out.println("");
out.println("Stat Update Report");
out.println("");
out.println("");
out.println("");
out.println("| Shared stat summary | "+mSummary+" |
|---|
");
out.println("| My stat summary | "+mStat.report()+" |
|---|
");
out.println("
");
out.println("");
out.println("");
}
}