📄 showitems.java
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package coreservlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
/** Servlet that displays a list of items being ordered.
* Accumulates them in an ArrayList with no attempt at
* detecting repeated items. Used to demonstrate basic
* session tracking. Updated to Java 5.
* <P>
* Taken from Core Servlets and JavaServer Pages 2nd Edition
* from Prentice Hall and Sun Microsystems Press,
* http://www.coreservlets.com/.
* © 2003 Marty Hall; may be freely used or adapted.
*/
@SuppressWarnings("unchecked")
public class ShowItems extends HttpServlet {
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
HttpSession session = request.getSession();
ArrayList<String> previousItems =
(ArrayList<String>)session.getAttribute("previousItems");
if (previousItems == null) {
previousItems = new ArrayList<String>();
session.setAttribute("previousItems", previousItems);
}
String newItem = request.getParameter("newItem");
if ((newItem != null) &&
(!newItem.trim().equals(""))) {
previousItems.add(newItem);
}
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String title = "Items Purchased";
String docType =
"<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 " +
"Transitional//EN\">\n";
out.println(docType +
"<HTML>\n" +
"<HEAD><TITLE>" + title + "</TITLE></HEAD>\n" +
"<BODY BGCOLOR=\"#FDF5E6\">\n" +
"<H1>" + title + "</H1>");
if (previousItems.size() == 0) {
out.println("<I>No items</I>");
} else {
out.println("<UL>");
for(String item: previousItems) {
out.println(" <LI>" + item);
}
out.println("</UL>");
}
out.println("</BODY></HTML>");
}
}
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