2 * Copyright (C) 2001, 2002 The Mir-coders group
4 * This file is part of Mir.
6 * Mir is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * Mir is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with Mir; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * In addition, as a special exception, The Mir-coders gives permission to link
21 * the code of this program with any library licensed under the Apache Software License,
22 * The Sun (tm) Java Advanced Imaging library (JAI), The Sun JIMI library
23 * (or with modified versions of the above that use the same license as the above),
24 * and distribute linked combinations including the two. You must obey the
25 * GNU General Public License in all respects for all of the code used other than
26 * the above mentioned libraries. If you modify this file, you may extend this
27 * exception to your version of the file, but you are not obligated to do so.
28 * If you do not wish to do so, delete this exception statement from your version.
32 import java.io.InputStream;
\r
33 import java.util.List;
\r
35 import mir.entity.Entity;
38 * Interface for Media handling in Mir. All media handlers
39 * must implement this interface. Each specific media type,
40 * be it Gif, Jpeg, Mp3 audio, Real Audio or quicktime video
41 * has special needs when it comes to representation on the various
42 * pages (article, list, summary), must be stored differently and has a
43 * different URL, etc... This interface allows Mir to support
44 * an infinite (I hope) number of media types. Once this is done,
45 * no code at any other level in Mir needs to be changed other than
46 * adding the content-type <-> media handler name mapping in the
47 * media_type table. The following is an example of the media_type
50 * id | name | mime_type | classname | tablename | dcname<br>
51 *---+---------+--------------------------+-----------+---------------+-------<br>
52 * 2 | unknown | application/octet-stream | -- | UploadedMedia | <br>
53 * 3 | jpg | image/gif | ImagesGif | Images | <br>
54 * 4 | mp3 | audio/mp3 | Audio | UploadedMedia | <br>
56 * The "id" field is used as a mapping in the table that contains the media type
57 * to the media_type table. For example, the images table has a to_media_type
58 * field that contains the id in the media_type table.
60 * The "name" field is used for various display/filenaming purposes. it should
61 * match a valid file extension name for a media_type (we could have used the
62 * content-type map for this....).
64 * The "mime_type" field is the most important as it does maps the type to Java
65 * classes (the storage and media_handler name). We call those classes using
66 * reflection. This way, once a Handler for a specific media type is implemented
67 * and entered into the media_type table, no other Mir code needs to be modified.
69 * The "classname" field is the name of the media handler (e.g MediaHandlerAudio)
70 * we use it to call the MediaHandler methods via reflection.
72 * The "tablename" is the name of the database storage classes (e.g DatabaseImages
73 * and EntityImages). We use this to fetch/storage the media (meta)data in the db.
75 * The "dcname" field is as of yet unused. Do search for "Dublin Core" on google
78 * Most media handlers should just extend MediaHandlerGeneric (i.e inherit from
79 * ) and just override the things that need to be specific. see MediaHandlerAudio
81 * @author <mh@nadir.org>, the Mir-coders group
82 * @version $Id: MirMedia.java,v 1.19 2003/09/03 18:29:01 zapata Exp $
85 public interface MirMedia{
88 * Takes the uploaded media data itself, along with the media Entity
89 * which contains the Media metadata plus the MediaType entity containing
90 * all the info for the specific media type itself. It's job is store the
91 * Media data (content) itself, this could be on the local filesystem, in the
92 * DB or even on a remote host. It then inserts the MetaData in the DB.
93 * @param InputStream, a stream of the uploaded data.
94 * @param ent, an Entity holding the media MetaData
95 * @param mediaType, an Entity holding the media_table entry
96 * @return boolean, success/fail
97 * @see mir.entity.Entity
99 public abstract void set (InputStream in, Entity ent, Entity mediaTypeEnt ) throws MediaExc, MediaFailure;
101 public abstract void produce (Entity ent, Entity mediaTypeEnt ) throws MediaExc, MediaFailure;
104 * Get's the media data from storage and returns it as an InputStream
105 * Not very useful for most media types as they are stored in a file,
106 * but very usefull for ones stored in the DB as it is necessary to get
107 * it first before making a file out of it (in Producer*).
108 * @param ent, an Entity holding the media MetaData
109 * @param mediaType, an Entity holding the media_table entry
110 * @return java.io.InputStream
111 * @see mir.entity.Entity
113 public abstract InputStream getMedia (Entity ent, Entity mediaTypeEnt) throws MediaExc, MediaFailure;
116 * Pretty much like get() above. But get's the specific Icon
117 * representation. useful for media stored in the DB.
118 * @param ent, an Entity holding the media MetaData
119 * @return java.io.InputStream
120 * @see mir.entity.Entity
122 public abstract InputStream getIcon (Entity ent) throws MediaExc, MediaFailure;
130 * @throws MediaFailure
132 public abstract String getIconMimeType (Entity aMediaEntity, Entity aMediaType) throws MediaExc, MediaFailure;
135 * gets the final content representation for the media
136 * in the form of a URL (String) that allows someone to
137 * download, look at or listen to the media. (HREF, img src
138 * streaming link, etc..)
139 * It should use the helper functions in the StringUtil class to
140 * build URL's safely, eliminating any *illegal* user input.
141 * @param ent, an Entity holding the media MetaData
142 * @param mediaTypeEnt, an Entity holding the media_table entry
143 * @return String, the url.
144 * @see mir.entity.Entity
145 * @see mir.misc.StringUtil
147 public abstract List getURL (Entity ent, Entity mediaTypeEnt) throws MediaExc, MediaFailure;
150 * Returns the absolute filesystem path to where the media
151 * content should be stored. This path is usually defined
152 * in the configuration wich is accessible through the MirConfig
154 * @return String, the path.
155 * @see mir.misc.MirConfig
157 public abstract String getStoragePath () throws MediaExc, MediaFailure;
160 * Returns the *relative* filesystem path to where the media
161 * icon content should be stored. It is relative to the path
162 * returned by getStoragePath()
163 * This path is usually defined
164 * in the configuration wich is accessible through the MirConfig
166 * @return String, the path.
167 * @see mir.misc.MirConfig
169 public abstract String getIconStoragePath () throws MediaExc, MediaFailure;
172 * Returns the base URL to that the media is accessible from
173 * to the end user. This could be a URL to another host.
174 * This is used in the Metadata stored in the DB and later on
175 * ,the templates use it.
176 * It is usually defined
177 * in the configuration witch is accessible through the MirConfig
179 * @return String, the base URL to the host.
180 * @see mir.misc.MirConfig
182 public abstract String getPublishHost () throws MediaExc, MediaFailure;
185 * Returns the file name of the Icon representing the media type.
186 * It is used in the summary view.
187 * It is usually defined
188 * in the configuration wich is accessible through the MirConfig
190 * @return String, the icon filename.
191 * @see mir.misc.MirConfig
193 public abstract String getBigIconName ();
196 * Returns the file name of the small Icon representing
198 * It is used in the right hand newswire list of the startpage.
199 * It is usually defined
200 * in the configuration wich is accessible through the MirConfig
202 * @return String, the icon filename.
203 * @see mir.misc.MirConfig
205 public abstract String getTinyIconName ();
208 * Returns the IMG SRC "ALT" text to be used
209 * for the Icon representations
210 * @return String, the ALT text.
212 public abstract String getIconAltName ();
215 * your can all figure it out.
218 public abstract boolean isVideo ();
221 * you can all figure it out.
224 public abstract boolean isAudio ();
227 * you can all figure it out.
230 public abstract boolean isImage ();
233 * returns a brief text dscription of what this
237 public abstract String getDescr (Entity mediaTypeEnt);