Java by API/java.rmi.server/UID — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
Admin (обсуждение | вклад) м (1 версия) |
(нет различий)
|
Текущая версия на 17:48, 31 мая 2010
new UID()
<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.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class ShoppingCartViewerRewrite extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException { res.setContentType("text/html"); PrintWriter out = res.getWriter(); out.println("<HEAD><TITLE>Current Shopping Cart Items</TITLE></HEAD>"); out.println("<BODY>"); // Get the current session ID, or generate one if necessary String sessionid = req.getPathInfo(); if (sessionid == null) { sessionid = generateSessionId(); } // 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:out.println("
"); if (items == null) { out.println("None"); } else {
- ");
for (int i = 0; i < items.length; i++) {
out.println("
- " + items[i]); } out.println("
} // Ask if the user wants to add more items or check out. // Include the session ID in the action URL. out.println("<FORM ACTION=\"/servlet/ShoppingCart/" + sessionid + "\" 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. Include the session ID in the URL. 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>