// Copyright 2004 The Apache Software Foundation
//
// Licensed 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.tapestry.wap.quiz;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.Serializable;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletContext;
import org.apache.hivemind.Resource;
import org.apache.tapestry.ApplicationServlet;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.engine.IPropertySource;
import org.apache.tapestry.request.RequestContext;
import org.apache.tapestry.resource.ContextResource;
import org.apache.tapestry.util.StringSplitter;
/**
* Global object for the Quiz application.
* This class has the following responsabilities:
* <ul>
* <li>Read questions from the specified files</li>
* <li>Provide questions by index</li>
* <li>Keep high scores in memory</li>
* </ul>
*
* @version $Id: Global.java,v 1.6 2004/06/21 19:11:52 hlship Exp $
* @author David Solis
*
**/
public class Global implements Serializable
{
private boolean init = false;
private int points[];
private String names[];
private static final List easyQuestions = new ArrayList();
private static final List mediumQuestions = new ArrayList();
private static final List hardQuestions = new ArrayList();
public static final int EASY_QUESTIONS = 1;
public static final int MEDIUM_QUESTIONS = 2;
public static final int HARD_QUESTIONS = 3;
public static final String EASY_LEVEL = "easy";
public static final String MEDIUM_LEVEL = "medium";
public static final String HARD_LEVEL = "hard";
public static final String QUESTION_KEY = "question";
public static final String ANSWER_KEY = "answer";
public static final String CHOICES_KEY = "choices";
public List getHighscores()
{
List result = new ArrayList();
for (int i = 0; i < 9; i++)
{
String name = names[i];
if (!"nobody".equals(name))
{
Map map = new HashMap();
map.put("name", name);
map.put("score", new Integer(points[i]));
result.add(map);
}
}
return result;
}
/**
* Checks if score is high scores
**/
public boolean isHighscore(int score)
{
return (score >= points[9]);
}
/**
* Checks if score is a new high score
**/
public boolean isNewHighscore(int score)
{
return (score > points[9]);
}
/**
* Adds score/name to the highscore table,
* returns position in highscore table or -1 if no highscore
**/
public int addHighscore(int score, String name)
{
int i = -1;
if (isNewHighscore(score))
{
for (i = 0; i <= 9; i++)
{
if (score > points[i])
break;
}
for (int j = 9; j >= i + 1; j--)
{
points[j] = points[j - 1];
names[j] = names[j - 1];
}
points[i] = score;
names[i] = name;
}
return i;
}
/**
* "getQuestionSet" method returns a number representing the right difficulty setting.
*
* @param level an <code>String</code> value
* @return an <code>int</code> value
*/
public int getQuestionSet(String level)
{
if (HARD_LEVEL.equals(level))
return HARD_QUESTIONS;
if (MEDIUM_LEVEL.equals(level))
return MEDIUM_QUESTIONS;
return EASY_QUESTIONS;
}
/**
* "getQuestion" method returns a String that contains the question, the alternatives and the correct answer.
*
* @param questionToBeAsked an <code>int</code> value
* @param questionSet an <code>int</code> value
* @return a <code>String</code> value
*/
public Map getQuestion(int questionToBeAsked, int questionSet)
{
String line;
List list;
switch (questionSet)
{
case EASY_QUESTIONS :
list = easyQuestions;
break;
case MEDIUM_QUESTIONS :
list = mediumQuestions;
break;
default :
list = hardQuestions;
break;
}
line = (String) list.get(questionToBeAsked);
StringSplitter splitter = new StringSplitter(';');
String[] result = splitter.splitToArray(line);
HashMap map = new HashMap();
map.put(QUESTION_KEY, result[0]);
int answer = Integer.parseInt(result[1]) - 1;
map.put(ANSWER_KEY, new Integer(answer));
int length = result.length - 2;
String[] choices = new String[length];
System.arraycopy(result, 2, choices, 0, length);
map.put(CHOICES_KEY, choices);
return map;
}
/**
* "getNumberOfQuestions" method returns the number of questions (Strings) in the questions table that is used.
*
* @param questionSet an <code>int</code> value
* @return an <code>int</code> value
*/
public int getNumberOfQuestions(int questionSet)
{
switch (questionSet)
{
case EASY_QUESTIONS :
return easyQuestions.size();
case MEDIUM_QUESTIONS :
return mediumQuestions.size();
default :
return hardQuestions.size();
}
}
public void initialize(IRequestCycle cycle)
{
if (!init)
{
RequestContext requestContext = cycle.getRequestContext();
ApplicationServlet servlet = requestContext.getServlet();
ServletContext context = servlet.getServletContext();
IPropertySource propertySource = cycle.getEngine().getPropertySource();
Resource webInfLocation = new ContextResource(context, "/WEB-INF/");
Resource webInfAppLocation =
webInfLocation.getRelativeResource(servlet.getServletName() + "/");
readQuestions(
easyQuestions,
webInfAppLocation,
propertySource.getPropertyValue("easyquestionsfile"));
readQuestions(
mediumQuestions,
webInfAppLocation,
propertySource.getPropertyValue("mediumquestiosfile"));
readQuestions(
hardQuestions,
webInfAppLocation,
propertySource.getPropertyValue("hardquestionsfile"));
points = new int[10];
names = new String[10];
for (int i = 0; i <= 9; i++)
{
points[i] = 0;
names[i] = "nobody";
}
init = true;
}
}
/**
* This method reads the questions from the appropriate file to the appropriate Vector.
*
* @param questions a <code>Vector</code> value
* @param questionsFile a <code>String</code> value
* @exception java.io.IOException if an error occurs
*/
private void readQuestions(List questions, String questionsFile) throws IOException
{
BufferedReader reader = null;
String line;
reader = new BufferedReader(new FileReader(questionsFile));
while ((line = reader.readLine()) != null)
{
if (line.trim().equals(""))
break;
questions.add(line);
}
}
private void readQuestions(List questions, Resource folder, String filename)
{
Resource resource = folder.getRelativeResource(filename);
URL url = resource.getResourceURL();
try
{
readQuestions(questions, url.getFile());
}
catch (IOException e)
{
e.printStackTrace(System.err);
}
}
}