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