001 /*
002 Licensed to the Apache Software Foundation (ASF) under one
003 or more contributor license agreements. See the NOTICE file
004 distributed with this work for additional information
005 regarding copyright ownership. The ASF licenses this file
006 to you under the Apache License, Version 2.0 (the
007 "License"); you may not use this file except in compliance
008 with the License. You may obtain a copy of the License at
009
010 http://www.apache.org/licenses/LICENSE-2.0
011
012 Unless required by applicable law or agreed to in writing,
013 software distributed under the License is distributed on an
014 "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 KIND, either express or implied. See the License for the
016 specific language governing permissions and limitations
017 under the License.
018 */
019 package org.apache.wiki.rss;
020
021 import java.util.ArrayList;
022 import java.util.List;
023
024 import javax.servlet.ServletContext;
025
026 import org.apache.commons.lang.StringEscapeUtils;
027 import org.apache.wiki.WikiContext;
028 import org.apache.wiki.WikiEngine;
029 import org.apache.wiki.api.exceptions.NoSuchVariableException;
030
031 /**
032 * Represents an abstract feed.
033 */
034 public abstract class Feed {
035 protected List<Entry> m_entries = new ArrayList<Entry>();
036
037 protected String m_feedURL;
038 protected String m_channelTitle;
039 protected String m_channelDescription;
040 protected String m_channelLanguage;
041
042 protected WikiContext m_wikiContext;
043
044 protected String m_mode = RSSGenerator.MODE_WIKI;
045
046 /**
047 * Wiki variable storing the blog's name.
048 */
049 public static final String VAR_BLOGNAME = "blogname";
050
051 /**
052 * Figure out a site name for a feed.
053 *
054 * @param context the wiki context
055 * @return the site name
056 */
057 public static String getSiteName(WikiContext context) {
058 WikiEngine engine = context.getEngine();
059
060 String blogname = null;
061
062 try {
063 blogname = engine.getVariableManager().getValue(context, VAR_BLOGNAME);
064 } catch (NoSuchVariableException e) {
065 }
066
067 if (blogname == null) {
068 blogname = engine.getApplicationName() + ": " + context.getPage().getName();
069 }
070
071 return blogname;
072 }
073
074 /**
075 * Create a new Feed for a particular WikiContext.
076 *
077 * @param context The WikiContext.
078 */
079 public Feed(WikiContext context) {
080 m_wikiContext = context;
081 }
082
083 /**
084 * Set the mode of the Feed. It can be any of the following:
085 * <ul>
086 * <li>{@link RSSGenerator#MODE_WIKI} - to create a wiki diff list per page.</li>
087 * <li>{@link RSSGenerator#MODE_BLOG} - to assume that the Entries are blog entries.</li>
088 * <li>{@link RSSGenerator#MODE_FULL} - to create a wiki diff list for the entire blog.</li>
089 * </ul>
090 * As the Entry list itself is generated elsewhere, this mostly just affects the way
091 * that the layout and metadata for each entry is generated.
092 *
093 * @param mode As defined in RSSGenerator.
094 */
095 public void setMode(String mode) {
096 m_mode = mode;
097 }
098
099 /**
100 * Adds a new Entry to the Feed, at the end of the list.
101 *
102 * @param e The Entry to add.
103 */
104 public void addEntry(Entry e) {
105 m_entries.add(e);
106 }
107
108 /**
109 * Returns the XML for the feed contents in a String format. All subclasses must implement.
110 *
111 * @return valid XML, ready to be shoved out.
112 */
113 public abstract String getString();
114
115 /**
116 * @return Returns the m_channelDescription.
117 */
118 public String getChannelDescription() {
119 return m_channelDescription;
120 }
121
122 /**
123 * @param description The m_channelDescription to set.
124 */
125 public void setChannelDescription(String description) {
126 m_channelDescription = description;
127 }
128
129 /**
130 * @return Returns the m_channelLanguage.
131 */
132 public String getChannelLanguage() {
133 return m_channelLanguage;
134 }
135
136 /**
137 * @param language The m_channelLanguage to set.
138 */
139 public void setChannelLanguage(String language) {
140 m_channelLanguage = language;
141 }
142
143 /**
144 * @return Returns the m_channelTitle.
145 */
146 public String getChannelTitle() {
147 return m_channelTitle;
148 }
149
150 /**
151 * @param title The m_channelTitle to set.
152 */
153 public void setChannelTitle(String title) {
154 m_channelTitle = title;
155 }
156
157 /**
158 * @return Returns the m_feedURL.
159 */
160 public String getFeedURL() {
161 return m_feedURL;
162 }
163
164 /**
165 * @param feedurl The m_feedURL to set.
166 */
167 public void setFeedURL(String feedurl) {
168 m_feedURL = feedurl;
169 }
170
171 /**
172 * A helper method for figuring out the MIME type for an enclosure.
173 *
174 * @param c A ServletContext
175 * @param name The filename
176 * @return Something sane for a MIME type.
177 */
178 protected String getMimeType(ServletContext c, String name) {
179 String type = c.getMimeType(name);
180
181 if (type == null) {
182 type = "application/octet-stream";
183 }
184
185 return type;
186 }
187
188 /**
189 * Does the required formatting and entity replacement for XML.
190 *
191 * @param s The String to format. Null is safe.
192 * @return A formatted string.
193 */
194 public static String format( String s ) {
195 return StringEscapeUtils.escapeXml( s );
196 }
197 }