| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package example; |
| |
| import java.io.IOException; |
| import java.util.*; |
| |
| import javax.servlet.ServletException; |
| import javax.servlet.http.*; |
| |
| public class GuestbookServlet extends ControllerServlet { |
| /** |
| * Stores the list of guestbook entries. |
| * |
| * <p>Note that for the sake of simplicity, this example |
| * does not try to store the guestbook persistenty. |
| */ |
| private ArrayList guestbook = new ArrayList(); |
| |
| public void indexAction(HttpServletRequest req, Page p) { |
| List snapShot; |
| synchronized (guestbook) { |
| snapShot = (List) guestbook.clone(); |
| } |
| p.put("guestbook", snapShot); |
| p.setTemplate("index.ftl"); |
| } |
| |
| public void formAction (HttpServletRequest req, Page p) |
| throws IOException, ServletException { |
| |
| p.put("name", noNull(req.getParameter("name"))); |
| p.put("email", noNull(req.getParameter("email"))); |
| p.put("message", noNull(req.getParameter("message"))); |
| List errors = (List) req.getAttribute("errors"); |
| p.put("errors", errors == null ? new ArrayList() : errors); |
| |
| p.setTemplate("form.ftl"); |
| } |
| |
| public void addAction (HttpServletRequest req, Page p) |
| throws IOException, ServletException { |
| List errors = new ArrayList(); |
| String name = req.getParameter("name"); |
| String email = req.getParameter("email"); |
| String message = req.getParameter("message"); |
| if (isBlank(name)) { |
| errors.add("You must give your name."); |
| } |
| if (isBlank(message)) { |
| errors.add("You must give a message."); |
| } |
| |
| // Was the sent data was correct? |
| if (errors.isEmpty()) { |
| if (email == null) email = ""; |
| // Create and insert the new guestbook entry. |
| GuestbookEntry e = new GuestbookEntry( |
| name.trim(), email.trim(), message); |
| synchronized (guestbook) { |
| guestbook.add(0, e); |
| } |
| // Show "Entry added" page. |
| p.put("entry", e); |
| p.setTemplate("add.ftl"); |
| } else { |
| // Go back to the page of the form |
| req.setAttribute("errors", errors); |
| p.setForward("form.a"); |
| } |
| } |
| |
| public static String noNull(String s) { |
| return s == null ? "" : s; |
| } |
| |
| public static boolean isBlank(String s) { |
| return s == null || s.trim().length() == 0; |
| } |
| } |