content: /**
   * 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 org.apache.aries.samples.blog.web;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.List;
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import javax.servlet.http.HttpSession;
  
  import org.apache.aries.samples.blog.api.BloggingService;
  import org.apache.aries.samples.blog.web.util.JNDIHelper;
  
  public class AddComment extends HttpServlet {
  	private static final long serialVersionUID = -920234218060948564L;
  	public static final String ERROR_MESSAGES_ID = "commentErrorMessages";
  
  	@Override
  	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
  			throws ServletException, IOException {
  
  		// email address of the comment's author
  		String email = req.getParameter("email");
  		// the id of the blog entry to which this comment is associated
  		long postId = Long.parseLong(req.getParameter("postId"));
  		// the text of the comment
  		String text = req.getParameter("text");
  
  		BloggingService service = JNDIHelper.getBloggingService();
  
  		// retrieve the blog entry and create the associated comment
  
  		if (service.getBlogAuthor(email) != null) {
  			service.createBlogComment(text, email, postId);
  			resp.sendRedirect("ViewBlog");
  		} else {
  
  			if (email.equals(""))
  				addError(req, "The email field is required.");
  			else
  				addError(req, "The email filed is not valid.");
  			resp.sendRedirect("AddCommentForm?postId=" + postId);
  		}
  	}
  
  	public static void addError(HttpServletRequest req, String error) {
  		HttpSession session = req.getSession();
  		if (session != null) {
  			@SuppressWarnings("unchecked")
  			List<String> errors = (List<String>) session
  					.getAttribute(ERROR_MESSAGES_ID);
  
  			if (errors == null) {
  				errors = new ArrayList<String>();
  				session.setAttribute(ERROR_MESSAGES_ID, errors);
  			}
  
  			errors.add(error);
  		}
  	}
  }
  