feedback.java

Java的wap push

package feedback;

import push.Winner;
import push.PushInitiator;
import members.Members;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

/**
 * Feedback class handles the feedback section of your WML home pages.
 * 
 * Initialization parameters: "questionsfile" determines the name of the file
 * containing your questions "feedbackfile" determines the name of the file
 * where the feedback is saved
 * 
 * The first line in your questionsfile contains the different choises the user
 * can choose from if the line starts with a "!" the answer will be a String
 * 
 * @version 1.0
 * @since 1.0
 * @see HttpServlet
 */
public final class Feedback extends HttpServlet {

	private static final String XML_VERSION = "<?xml version=\"1.0\"?>";
	private static final String CONTENT_TYPE = "text/vnd.wap.wml";
	private static final String DOC_TYPE = "<!DOCTYPE wml PUBLIC \"-//WAPFORUM//DTD WML 1.1//EN\"\n"
			+ "  \"http://www.wapforum.org/DTD/wml_1.1.xml\">";

	private static int numberOfQuestions = 0;
	private static String grades;
	private static final Vector questions = new Vector();
	private static final String HOME_PAGE = "/index.jsp";
	private static String feedbackFile = null;

	private static Winner winner = null;

	/**
	 * This is the initialization code that runs only once. (when you start the
	 * servlet) The servlet is being placed into service.
	 */
	public void init() throws ServletException {
		String questionsFile = getInitParameter("questionsfile");
		questionsFile = getServletContext().getRealPath(questionsFile);
		feedbackFile = getInitParameter("feedbackfile");
		feedbackFile = getServletContext().getRealPath(feedbackFile);

		try {
			BufferedReader reader = new BufferedReader(new FileReader(
					questionsFile));
			grades = reader.readLine();
			String line;
			while ((line = reader.readLine()) != null) {
				if (line.trim().equals(""))
					break;
				questions.add(line);
			}
		} catch (java.io.IOException e) {
			System.err.println(e);
		}
		numberOfQuestions = questions.size();
	}

	/**
	 * Called by the server to allow a servlet to handle a GET request.
	 * 
	 * @param request
	 *            a <code>HttpServletRequest</code> value
	 * @param response
	 *            a <code>HttpServletResponse</code> value
	 * @exception ServletException
	 *                if an error occurs
	 * @exception IOException
	 *                if an error occurs
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doPost(request, response);
	}

	/**
	 * Called by the server to allow a servlet to handle a POST request.
	 * 
	 * @param request
	 *            a <code>HttpServletRequest</code> value
	 * @param response
	 *            a <code>HttpServletResponse</code> value
	 * @exception ServletException
	 *                if an error occurs
	 * @exception IOException
	 *                if an error occurs
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		/* Session tracking. See the description in index.jsp */
		HttpSession session = request.getSession();
		boolean cookiesCheck = request.getHeader("cookie") != null
				&& request.isRequestedSessionIdValid();
		final String jsessionID = cookiesCheck ? "" : ";jsessionid="
				+ session.getId();

		/*
		 * Initialize a winner selecting thread that selects a winner from the
		 * set of users who has given feedback. It will send a push message to
		 * the winner
		 */
		if (winner == null) {
			PushInitiator pusher = Members.getInitiator();
			if (pusher != null) {
				winner = new Winner(pusher, "http://" + request.getServerName()
						+ ":" + request.getServerPort()
						+ request.getContextPath() + "/services/winner.jsp",
						Members.getPushAddressType());
				new Thread(winner).start();
			}
		}

		/* start generating the response ... */
		response.setContentType(CONTENT_TYPE);
		PrintWriter out = response.getWriter();

		out.println(XML_VERSION);
		out.println(DOC_TYPE);
		out.println("<wml>");

		out.println("<!-- provides a way back using the prev element -->\n"
				+ "<template>" + " <do type=\"prev\">" + "  <prev/>" + " </do>"
				+ "</template>");

		if (request.getParameter("action") == null) {
			out.println("<!-- questions card -->\n"
					+ "<card title=\"Feedback\" id=\"questionsCard\">"
					+ "<do type=\"accept\" label=\"Send form\">"
					+ "<go method=\"post\" href=\"" + request.getRequestURI()
					+ jsessionID + "\">");
			for (int i = 0; i < numberOfQuestions; ++i)
				out.println("<postfield name=\"answer" + i
						+ "\" value=\"$(choise" + i + ")\"/>");
			out.println("<postfield name=\"action\" value=\"write\"/>");
			out.println("<postfield name=\"sendname\" value=\"$(sendname)\"/>");
			out.println("</go></do>"
					+ "<p>Please grade our mobile service:<br/>");
			String gradesOut = "";
			StringTokenizer st = new StringTokenizer(grades);
			for (int j = 1; st.hasMoreTokens(); ++j)
				gradesOut = gradesOut + "<option value=\"" + j + "\">"
						+ st.nextToken() + "</option>\n";

			for (int i = 0; i < numberOfQuestions; ++i) {
				String question = (String) questions.get(i);
				if (question.startsWith("!")) {
					out.println(question.substring(1) + "&#160;");
					out.println("<input name=\"choise" + i + "\"/>");
				} else {
					out.println(question + "&#160;");
					out.println("<select value=\"Empty\" title=\"" + question
							+ "\" name=\"choise" + i + "\">");
					out.println("<option value=\"Empty\">Select</option>");
					out.println(gradesOut);
					out.println("</select>");
				}
			}

			if (session.getAttribute("name") != null) {
				out.println("<select name=\"sendname\" value=\"yes\">"
						+ "<option value=\"yes\">Include name</option>"
						+ "<option value=\"no\">Do not include name</option>"
						+ "</select>");
			}
			out.println("<anchor title=\"Send form\">Send form"
					+ "<go method=\"post\" href=\"" + request.getRequestURI()
					+ jsessionID + "\">");
			for (int i = 0; i < numberOfQuestions; ++i)
				out.println("<postfield name=\"answer" + i
						+ "\" value=\"$(choise" + i + ")\"/>");
			out.println("<postfield name=\"action\" value=\"write\"/>");
			out.println("<postfield name=\"sendname\" value=\"$(sendname)\"/>");
			out.println("</go></anchor></p>" + "</card>");
		} else {
			out
					.println("<!-- Thanks about the feedback -->\n"
							+ "<card title=\"Thank you\" id=\"thanks\">"
							+ " <do type=\"accept\" label=\"Ok\">"
							+ "  <go href=\""
							+ request.getContextPath()
							+ HOME_PAGE
							+ jsessionID
							+ "\"/>"
							+ " </do>"
							+ " <p>Your message has been delivered.<br/>Thank you for your feedback!<br/>"
							+ ((session.getAttribute("name") != null) ? "Note! Each member feedback (if name included) enters a draw for wonderful prizes.<br/>"
									: "")
							+ " <anchor title=\"Info pages\">Info pages"
							+ "  <go href=\"" + request.getContextPath()
							+ HOME_PAGE + jsessionID + "\"/>" + " </anchor>"
							+ " </p>" + "</card>");

			/* finally, update the feedback file. */
			synchronized (feedbackFile) {
				PrintWriter writer = new PrintWriter(new FileOutputStream(
						feedbackFile, true), true);
				for (int i = 0; i < numberOfQuestions; ++i) {
					String answer = request.getParameter("answer" + i);
					writer.print(answer + ";");
				}
				if (request.getParameter("sendname") != null
						&& request.getParameter("sendname").equals("yes"))
					writer.println((String) session.getAttribute("name"));
				else
					writer.println();
				writer.flush();
			}
		}
		out.println("</wml>");

	}

	/**
	 * <code>viewVotes</code> views the information related to received
	 * feedbacks, i.e., average grades for each question.
	 * 
	 * @return a <code>String</code> value
	 */
	public static String viewVotes() {
		String returnStr = "";
		try {
			int numberOfLines = 0;
			double[] stats = new double[numberOfQuestions];
			int[] empty = new int[numberOfQuestions];
			synchronized (feedbackFile) {
				BufferedReader reader = new BufferedReader(new FileReader(
						feedbackFile));
				StringTokenizer st = null;
				String line;
				while ((line = reader.readLine()) != null) {
					st = new StringTokenizer(line, ";");
					for (int i = 0; i < numberOfQuestions; ++i) {
						String token = st.nextToken();
						if (!(token.equals("Empty")))
							stats[i] = stats[i] + Integer.parseInt(token);
						else
							++empty[i];
					}
					++numberOfLines;
				}
			}
			for (int j = 0; j < numberOfQuestions; ++j)
				returnStr = returnStr
						+ questions.get(j)
						+ ": "
						+ Math.rint(100.0 * stats[j]
								/ (numberOfLines - empty[j])) / 100.0 + "<br/>";
			returnStr = returnStr + "Votes: " + numberOfLines;
		} catch (Exception e) {
			System.err.println(e);
		}
		return returnStr;
	}

	/**
	 * Selects winner from a set of users who have returned feedback
	 * 
	 * @param feedbackFile
	 *            a <code>String</code> value
	 * @return a <code>String</code> value
	 */
	public static String winner() {
		try {
			synchronized (feedbackFile) {
				BufferedReader reader = new BufferedReader(new FileReader(
						feedbackFile));
				int numberOfPossibilities = 0;
				while (reader.readLine() != null)
					++numberOfPossibilities;
				int winner = 1 + (int) (Math.random() * numberOfPossibilities);
				String winnerStr = "";
				reader = new BufferedReader(new FileReader(feedbackFile));
				for (int i = 0; i < winner; ++i)
					winnerStr = reader.readLine();
				StringTokenizer st = new StringTokenizer(winnerStr, ";");
				while (st.hasMoreTokens())
					winnerStr = st.nextToken();
				return winnerStr;
			}
		} catch (FileNotFoundException e) {
		} catch (IOException e) {
		}
		return "";
	}

}