/**
* Simple Shopping Cart V2
*
* Session tracking with URL rewriting. Note that the simplified
* session number generation here is not safe (easy to guess) or
* thread-safe.
*/
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class Cart2 extends HttpServlet {
int sss;
HashMap cart;
/**
* Create a form
*/
String createForm( String sess )
{
String form="";
String method = "method=post";
String action = "action=Cart2?sess=" + sess;
String e1 = "Item:
";
String e2 = "";
String e3 = "
";
form += "";
return form;
}
/**
* Create a list of items already bought
*/
String createList( String sess )
{
Vector v = (Vector) cart.get(sess);
String list = "";
for( int i=0 ; i < v.size() ; ++i )
if( v.elementAt(i) != null )
list += (String) v.elementAt(i) + "
";
return list;
}
/** init() */
public void init() throws ServletException
{
sss = 0;
cart = new HashMap();
}
/** doGet() */
public void doGet( HttpServletRequest request, HttpServletResponse response )
throws ServletException, IOException
{
String sess;
if( request.getParameter("sess") == null )
{
sess = "" + sss++;
cart.put( sess, new Vector() );
}
else
sess = request.getParameter("sess");
if( request.getParameter("buy") != null )
((Vector) cart.get(sess)).add( request.getParameter("item") );
// doc type, html, title, body
response.setContentType("text/html");
String doc = "\n";
doc += "Simple Shopping Cart\n";
if( request.getParameter("done") != null ) doc += createList(sess);
else doc += createForm(sess);
// closing body and html. set content type to be html and write out
doc += "";
PrintWriter out = response.getWriter();
out.println( doc );
}
public void doPost( HttpServletRequest request, HttpServletResponse response )
throws ServletException, IOException
{
doGet( request, response );
}
}