Java by API/javax.servlet.http/Cookie

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Cookie: getValue()

   <source lang="java">

import java.io.IOException; import java.io.PrintWriter; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import javax.servlet.ServletException; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class ShoppingCartViewerCookie extends HttpServlet { 

 public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException,
     IOException {
   res.setContentType("text/html");
   PrintWriter out = res.getWriter();
   String sessionid = null;
   Cookie[] cookies = req.getCookies();
   if (cookies != null) {
     for (int i = 0; i < cookies.length; i++) {
       if (cookies[i].getName().equals("sessionid")) {
         sessionid = cookies[i].getValue();
         break;
       }
     }
   }
   // If the session ID wasn"t sent, generate one.
   // Then be sure to send it to the client with the response.
   if (sessionid == null) {
     sessionid = generateSessionId();
     Cookie c = new Cookie("sessionid", sessionid);
     res.addCookie(c);
   }
   out.println("<HEAD><TITLE>Current Shopping Cart Items</TITLE></HEAD>");
   out.println("<BODY>");
   // Cart items are associated with the session ID
   String[] items = getItemsFromCart(sessionid);
   // Print the current cart items.
   out.println("You currently have the following items in your cart:
");
   if (items == null) {
     out.println("None");
   } else {
out.println("
    "); for (int i = 0; i < items.length; i++) { out.println("
  • " + items[i]); } out.println("
"); 
   }
   // Ask if they want to add more items or check out.
   out.println("<FORM ACTION=\"/servlet/ShoppingCart\" METHOD=POST>");
   out.println("Would you like to
");
   out.println("<INPUT TYPE=SUBMIT VALUE=\" Add More Items \">");
   out.println("<INPUT TYPE=SUBMIT VALUE=\" Check Out \">");
   out.println("</FORM>");
   // Offer a help page.
   out.println("For help, click ");
   out.println("</BODY></HTML>");
 }
 private static String generateSessionId() throws UnsupportedEncodingException {
   String uid = new java.rmi.server.UID().toString(); // guaranteed unique
   return URLEncoder.encode(uid,"UTF-8"); // encode any special chars
 }
 private static String[] getItemsFromCart(String sessionid) {
   return new String[]{"a","b"};  
 }

} 

      </source>



new Cookie(String name, String value)

   <source lang="java">

import java.io.IOException; import java.io.PrintWriter; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import javax.servlet.ServletException; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class ShoppingCartViewerCookie extends HttpServlet { 

 public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException,
     IOException {
   res.setContentType("text/html");
   PrintWriter out = res.getWriter();
   String sessionid = null;
   Cookie[] cookies = req.getCookies();
   if (cookies != null) {
     for (int i = 0; i < cookies.length; i++) {
       if (cookies[i].getName().equals("sessionid")) {
         sessionid = cookies[i].getValue();
         break;
       }
     }
   }
   // If the session ID wasn"t sent, generate one.
   // Then be sure to send it to the client with the response.
   if (sessionid == null) {
     sessionid = generateSessionId();
     Cookie c = new Cookie("sessionid", sessionid);
     res.addCookie(c);
   }
   out.println("<HEAD><TITLE>Current Shopping Cart Items</TITLE></HEAD>");
   out.println("<BODY>");
   // Cart items are associated with the session ID
   String[] items = getItemsFromCart(sessionid);
   // Print the current cart items.
   out.println("You currently have the following items in your cart:
");
   if (items == null) {
     out.println("None");
   } else {
out.println("
    "); for (int i = 0; i < items.length; i++) { out.println("
  • " + items[i]); } out.println("
"); 
   }
   // Ask if they want to add more items or check out.
   out.println("<FORM ACTION=\"/servlet/ShoppingCart\" METHOD=POST>");
   out.println("Would you like to
");
   out.println("<INPUT TYPE=SUBMIT VALUE=\" Add More Items \">");
   out.println("<INPUT TYPE=SUBMIT VALUE=\" Check Out \">");
   out.println("</FORM>");
   // Offer a help page.
   out.println("For help, click ");
   out.println("</BODY></HTML>");
 }
 private static String generateSessionId() throws UnsupportedEncodingException {
   String uid = new java.rmi.server.UID().toString(); // guaranteed unique
   return URLEncoder.encode(uid,"UTF-8"); // encode any special chars
 }
 private static String[] getItemsFromCart(String sessionid) {
   return new String[]{"a","b"};  
 }

} 

      </source>
Источник — «http://jexp.ru/index.php?title=Java_by_API/javax.servlet.http/Cookie&oldid=1750»