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 the com.oreilly.servlet library, any library
22 * licensed under the Apache Software License, The Sun (tm) Java Advanced
23 * Imaging library (JAI), The Sun JIMI library (or with modified versions of
24 * the above that use the same license as the above), and distribute linked
25 * combinations including the two. You must obey the GNU General Public
26 * License in all respects for all of the code used other than the above
27 * mentioned libraries. If you modify this file, you may extend this exception
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29 * not wish to do so, delete this exception statement from your version.
32 package mircoders.storage;
34 import mir.entity.Entity;
35 import mir.entity.EntityRelation;
36 import mir.log.LoggerWrapper;
37 import mir.storage.Database;
38 import mir.storage.StorageObject;
39 import mir.storage.StorageObjectExc;
40 import mir.storage.StorageObjectFailure;
43 * <b>Diese Klasse implementiert die Datenbankverbindung zur MetaObjekt-Tabelle
48 public class DatabaseMedia extends Database implements StorageObject{
50 private static DatabaseMedia instance;
51 private static EntityRelation relationMediaType;
53 // the following *has* to be sychronized cause this static method
54 // could get preemted and we could end up with 2 instances of DatabaseFoo..
55 // see the "Singletons with needles and thread" article at JavaWorld -mh
56 public synchronized static DatabaseMedia getInstance() {
57 if (instance == null) {
58 instance = new DatabaseMedia();
59 instance.myselfDatabase = instance;
64 private DatabaseMedia() {
67 logger = new LoggerWrapper("Database.Media");
72 new EntityRelation("to_media_type", "id", DatabaseMediaType.getInstance(), EntityRelation.TO_ONE);
73 theEntityClass = mircoders.entity.EntityMedia.class;
80 * returns the comments that belong to the article (via entityrelation)
81 * where db-flag is_published is true
83 public Entity getMediaType(Entity ent) throws StorageObjectFailure, StorageObjectExc {
85 return relationMediaType.getOne(ent);
88 logger.error("failed to get media_type: " + e.getMessage());
89 throw new StorageObjectFailure("DatabaseMedia.getMediaType :" + e.getMessage(),e);