src/main/java/net/pterodactylus/demoscenemusic/core/TemplateServlet.java

   1 /*
   2  * DemosceneMusic - TemplateServlet.java - Copyright © 2012 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.demoscenemusic.core;
  19
  20 import java.io.ByteArrayInputStream;
  21 import java.io.ByteArrayOutputStream;
  22 import java.io.IOException;
  23 import java.io.InputStream;
  24 import java.io.InputStreamReader;
  25 import java.io.Reader;
  26 import java.io.UnsupportedEncodingException;
  27 import java.lang.reflect.InvocationTargetException;
  28 import java.net.URISyntaxException;
  29 import java.util.Comparator;
  30 import java.util.Enumeration;
  31 import java.util.HashMap;
  32 import java.util.Map;
  33
  34 import javax.servlet.ServletConfig;
  35 import javax.servlet.ServletException;
  36 import javax.servlet.http.HttpServlet;
  37 import javax.servlet.http.HttpServletRequest;
  38 import javax.servlet.http.HttpServletResponse;
  39
  40 import net.pterodactylus.demoscenemusic.data.Artist;
  41 import net.pterodactylus.demoscenemusic.data.Style;
  42 import net.pterodactylus.demoscenemusic.data.Track;
  43 import net.pterodactylus.demoscenemusic.page.ServletRequest;
  44 import net.pterodactylus.util.io.Closer;
  45 import net.pterodactylus.util.io.StreamCopier;
  46 import net.pterodactylus.util.template.ClassPathTemplateProvider;
  47 import net.pterodactylus.util.template.CollectionSortFilter;
  48 import net.pterodactylus.util.template.HtmlFilter;
  49 import net.pterodactylus.util.template.ReflectionAccessor;
  50 import net.pterodactylus.util.template.Template;
  51 import net.pterodactylus.util.template.TemplateContextFactory;
  52 import net.pterodactylus.util.template.TemplateParser;
  53 import net.pterodactylus.util.web.Header;
  54 import net.pterodactylus.util.web.Page;
  55 import net.pterodactylus.util.web.Response;
  56
  57 /**
  58  * TODO
  59  *
  60  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  61  */
  62 public class TemplateServlet extends HttpServlet {
  63
  64         private Core core;
  65         private final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  66
  67         private final Map<String, Page<ServletRequest>> pages = new HashMap<String, Page<ServletRequest>>();
  68
  69         //
  70         // SERVLET METHODS
  71         //
  72
  73         /**
  74          * {@inheritDoc}
  75          */
  76         @Override
  77         public void init(ServletConfig config) throws ServletException {
  78                 super.init(config);
  79                 core = (Core) config.getServletContext().getAttribute("core");
  80
  81                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  82
  83                 templateContextFactory.addFilter("html", new HtmlFilter());
  84                 CollectionSortFilter sortFilter = new CollectionSortFilter();
  85                 sortFilter.addComparator(Artist.class, new Comparator<Artist>() {
  86
  87                         @Override
  88                         public int compare(Artist leftArtist, Artist rightArtist) {
  89                                 return leftArtist.getName().compareToIgnoreCase(rightArtist.getName());
  90                         }
  91
  92                 });
  93                 sortFilter.addComparator(Track.class, new Comparator<Track>() {
  94
  95                         @Override
  96                         public int compare(Track leftTrack, Track rightTrack) {
  97                                 return leftTrack.getName().compareToIgnoreCase(rightTrack.getName());
  98                         }
  99
 100                 });
 101                 sortFilter.addComparator(Style.class, new Comparator<Style>() {
 102
 103                         @Override
 104                         public int compare(Style leftStyle, Style rightStyle) {
 105                                 return leftStyle.getName().compareToIgnoreCase(rightStyle.getName());
 106                         }
 107
 108                 });
 109                 templateContextFactory.addFilter("sort", sortFilter);
 110
 111                 templateContextFactory.addTemplateObject("core", core);
 112                 templateContextFactory.addTemplateObject("dataManager", core.getDataManager());
 113
 114                 templateContextFactory.addProvider(new ClassPathTemplateProvider(getClass(), "/templates/"));
 115
 116                 for (@SuppressWarnings("rawtypes")
 117                 Enumeration parameterNames = config.getInitParameterNames(); parameterNames.hasMoreElements();) {
 118                         String pageName = (String) parameterNames.nextElement();
 119                         Template template = getTemplate(pageName);
 120                         String pageClassName = config.getInitParameter(pageName);
 121                         try {
 122                                 Class<?> pageClass = Class.forName(pageClassName);
 123                                 @SuppressWarnings("unchecked")
 124                                 Page<ServletRequest> page = (Page<ServletRequest>) pageClass.getConstructor(Core.class, TemplateContextFactory.class, Template.class).newInstance(core, templateContextFactory, template);
 125                                 pages.put(pageName, page);
 126                         } catch (ClassNotFoundException cnfe1) {
 127                                 cnfe1.printStackTrace();
 128                         } catch (IllegalArgumentException iae1) {
 129                                 iae1.printStackTrace();
 130                         } catch (SecurityException se1) {
 131                                 se1.printStackTrace();
 132                         } catch (InstantiationException ie1) {
 133                                 ie1.printStackTrace();
 134                         } catch (IllegalAccessException iae1) {
 135                                 iae1.printStackTrace();
 136                         } catch (InvocationTargetException ite1) {
 137                                 ite1.printStackTrace();
 138                         } catch (NoSuchMethodException nsme1) {
 139                                 nsme1.printStackTrace();
 140                         }
 141                 }
 142         }
 143
 144         /**
 145          * {@inheritDoc}
 146          */
 147         @Override
 148         protected void doGet(HttpServletRequest request, HttpServletResponse httpServletResponse) throws ServletException, IOException {
 149                 String path = request.getPathInfo();
 150                 if (path.startsWith("/")) {
 151                         path = path.substring(1);
 152                 }
 153                 Page<ServletRequest> page = pages.get(path);
 154                 if (page != null) {
 155                         ServletRequest servletRequest;
 156                         try {
 157                                 servletRequest = new ServletRequest(request);
 158                         } catch (URISyntaxException use1) {
 159                                 throw new IOException("Could not create URI from " + request.getRequestURI(), use1);
 160                         }
 161                         ByteArrayOutputStream responseOutputBuffer = new ByteArrayOutputStream();
 162                         Response response = new Response(responseOutputBuffer);
 163                         response = page.handleRequest(servletRequest, response);
 164                         for (Header header : response.getHeaders()) {
 165                                 for (String value : header) {
 166                                         httpServletResponse.addHeader(header.getName(), value);
 167                                 }
 168                         }
 169                         httpServletResponse.setContentType(response.getContentType());
 170                         httpServletResponse.setStatus(response.getStatusCode());
 171                         StreamCopier.copy(new ByteArrayInputStream(responseOutputBuffer.toByteArray()), httpServletResponse.getOutputStream());
 172                         return;
 173                 }
 174         }
 175
 176         //
 177         // PRIVATE METHODS
 178         //
 179
 180         private Template getTemplate(String pageName) {
 181                 InputStream templateInputStream = getClass().getResourceAsStream("/templates/" + pageName);
 182                 if (templateInputStream == null) {
 183                         return null;
 184                 }
 185                 Reader templateReader = null;
 186                 try {
 187                         templateReader = new InputStreamReader(templateInputStream, "UTF-8");
 188                         return TemplateParser.parse(templateReader);
 189                 } catch (UnsupportedEncodingException uee1) {
 190                         /* can not happen. */
 191                         throw new RuntimeException("Could not parse templates!", uee1);
 192                 } finally {
 193                         Closer.close(templateReader);
 194                         Closer.close(templateInputStream);
 195                 }
 196         }
 197
 198 }