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.data.User;
  44 import net.pterodactylus.demoscenemusic.page.ServletRequest;
  45 import net.pterodactylus.demoscenemusic.template.UserAccessor;
  46 import net.pterodactylus.util.io.Closer;
  47 import net.pterodactylus.util.io.StreamCopier;
  48 import net.pterodactylus.util.template.ClassPathTemplateProvider;
  49 import net.pterodactylus.util.template.CollectionSortFilter;
  50 import net.pterodactylus.util.template.HtmlFilter;
  51 import net.pterodactylus.util.template.ReflectionAccessor;
  52 import net.pterodactylus.util.template.Template;
  53 import net.pterodactylus.util.template.TemplateContextFactory;
  54 import net.pterodactylus.util.template.TemplateParser;
  55 import net.pterodactylus.util.web.Header;
  56 import net.pterodactylus.util.web.Page;
  57 import net.pterodactylus.util.web.Response;
  58
  59 /**
  60  * TODO
  61  *
  62  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  63  */
  64 public class TemplateServlet extends HttpServlet {
  65
  66         private Core core;
  67         private final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  68
  69         private final Map<String, Page<ServletRequest>> pages = new HashMap<String, Page<ServletRequest>>();
  70
  71         //
  72         // SERVLET METHODS
  73         //
  74
  75         /**
  76          * {@inheritDoc}
  77          */
  78         @Override
  79         public void init(ServletConfig config) throws ServletException {
  80                 super.init(config);
  81                 core = (Core) config.getServletContext().getAttribute("core");
  82
  83                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  84                 templateContextFactory.addAccessor(User.class, new UserAccessor());
  85
  86                 templateContextFactory.addFilter("html", new HtmlFilter());
  87                 CollectionSortFilter sortFilter = new CollectionSortFilter();
  88                 sortFilter.addComparator(Artist.class, new Comparator<Artist>() {
  89
  90                         @Override
  91                         public int compare(Artist leftArtist, Artist rightArtist) {
  92                                 return leftArtist.getName().compareToIgnoreCase(rightArtist.getName());
  93                         }
  94
  95                 });
  96                 sortFilter.addComparator(Track.class, new Comparator<Track>() {
  97
  98                         @Override
  99                         public int compare(Track leftTrack, Track rightTrack) {
 100                                 return leftTrack.getName().compareToIgnoreCase(rightTrack.getName());
 101                         }
 102
 103                 });
 104                 sortFilter.addComparator(Style.class, new Comparator<Style>() {
 105
 106                         @Override
 107                         public int compare(Style leftStyle, Style rightStyle) {
 108                                 return leftStyle.getName().compareToIgnoreCase(rightStyle.getName());
 109                         }
 110
 111                 });
 112                 templateContextFactory.addFilter("sort", sortFilter);
 113
 114                 templateContextFactory.addTemplateObject("core", core);
 115                 templateContextFactory.addTemplateObject("dataManager", core.getDataManager());
 116
 117                 templateContextFactory.addProvider(new ClassPathTemplateProvider(getClass(), "/templates/"));
 118
 119                 for (@SuppressWarnings("rawtypes")
 120                 Enumeration parameterNames = config.getInitParameterNames(); parameterNames.hasMoreElements();) {
 121                         String pageName = (String) parameterNames.nextElement();
 122                         Template template = getTemplate(pageName);
 123                         String pageClassName = config.getInitParameter(pageName);
 124                         try {
 125                                 Class<?> pageClass = Class.forName(pageClassName);
 126                                 @SuppressWarnings("unchecked")
 127                                 Page<ServletRequest> page = (Page<ServletRequest>) pageClass.getConstructor(Core.class, TemplateContextFactory.class, Template.class).newInstance(core, templateContextFactory, template);
 128                                 pages.put(pageName, page);
 129                         } catch (ClassNotFoundException cnfe1) {
 130                                 cnfe1.printStackTrace();
 131                         } catch (IllegalArgumentException iae1) {
 132                                 iae1.printStackTrace();
 133                         } catch (SecurityException se1) {
 134                                 se1.printStackTrace();
 135                         } catch (InstantiationException ie1) {
 136                                 ie1.printStackTrace();
 137                         } catch (IllegalAccessException iae1) {
 138                                 iae1.printStackTrace();
 139                         } catch (InvocationTargetException ite1) {
 140                                 ite1.printStackTrace();
 141                         } catch (NoSuchMethodException nsme1) {
 142                                 nsme1.printStackTrace();
 143                         }
 144                 }
 145         }
 146
 147         /**
 148          * {@inheritDoc}
 149          */
 150         @Override
 151         protected void doGet(HttpServletRequest request, HttpServletResponse httpServletResponse) throws ServletException, IOException {
 152                 String path = request.getPathInfo();
 153                 if (path.startsWith("/")) {
 154                         path = path.substring(1);
 155                 }
 156                 Page<ServletRequest> page = pages.get(path);
 157                 if (page != null) {
 158                         ServletRequest servletRequest;
 159                         try {
 160                                 servletRequest = new ServletRequest(request);
 161                         } catch (URISyntaxException use1) {
 162                                 throw new IOException("Could not create URI from " + request.getRequestURI(), use1);
 163                         }
 164                         ByteArrayOutputStream responseOutputBuffer = new ByteArrayOutputStream();
 165                         Response response = new Response(responseOutputBuffer);
 166                         response = page.handleRequest(servletRequest, response);
 167                         for (Header header : response.getHeaders()) {
 168                                 for (String value : header) {
 169                                         httpServletResponse.addHeader(header.getName(), value);
 170                                 }
 171                         }
 172                         httpServletResponse.setContentType(response.getContentType());
 173                         httpServletResponse.setStatus(response.getStatusCode());
 174                         StreamCopier.copy(new ByteArrayInputStream(responseOutputBuffer.toByteArray()), httpServletResponse.getOutputStream());
 175                         return;
 176                 }
 177         }
 178
 179         //
 180         // PRIVATE METHODS
 181         //
 182
 183         private Template getTemplate(String pageName) {
 184                 InputStream templateInputStream = getClass().getResourceAsStream("/templates/" + pageName);
 185                 if (templateInputStream == null) {
 186                         return null;
 187                 }
 188                 Reader templateReader = null;
 189                 try {
 190                         templateReader = new InputStreamReader(templateInputStream, "UTF-8");
 191                         return TemplateParser.parse(templateReader);
 192                 } catch (UnsupportedEncodingException uee1) {
 193                         /* can not happen. */
 194                         throw new RuntimeException("Could not parse templates!", uee1);
 195                 } finally {
 196                         Closer.close(templateReader);
 197                         Closer.close(templateInputStream);
 198                 }
 199         }
 200
 201 }