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.
30 package mir.entity.adapter;
32 import mir.entity.Entity;
33 import mir.util.CachingRewindableIterator;
34 import mir.util.RewindableIterator;
38 /** An EntityAdapter is a wrapper around an Entity meant to add
39 * missing functionality. It provides "calculated fields"
40 * which mir installations can extend reasonably easilly.
41 * "calculated fields" compute values that are not directly present
42 * in the db table. For example:
43 * a field to have the number of comments associated with an article;
44 * a field to get the list of hidden comments associated with an article;
46 * <p>This whole framework is meant to be replaced by hibernate</p>
48 public class EntityAdapter {
49 private Entity entity;
50 private EntityAdapterDefinition definition;
51 private Map calculatedFieldsCache;
52 private EntityAdapterModel model;
54 public EntityAdapter(Entity anEntity, EntityAdapterDefinition aDefinition, EntityAdapterModel aModel) {
56 definition = aDefinition;
57 calculatedFieldsCache = new HashMap();
61 public boolean equals(Object anObject) {
62 return anObject instanceof EntityAdapter
63 && ((EntityAdapter) anObject).entity.equals(entity);
66 public int hashCode() {
68 return entity.hashCode();
75 public Entity getEntity() {
79 public EntityAdapterModel getModel() {
83 public Object get(String aKey) {
86 if (calculatedFieldsCache.containsKey(aKey)) {
87 return calculatedFieldsCache.get(aKey);
89 else if (aKey instanceof String && definition.hasCalculatedField((String) aKey)) {
90 result = definition.getCalculatedField((String) aKey).getValue(this);
91 calculatedFieldsCache.put(aKey, result);
96 return entity.getFieldValue((String) aKey);
100 public Iterator getIterator(String aKey) {
101 Object result = get(aKey);
103 if (result instanceof RewindableIterator) {
104 ((RewindableIterator) result).rewind();
105 return (RewindableIterator) result;
107 else if (result instanceof Iterator) {
108 return (Iterator) result;
110 else if (result instanceof Collection) {
111 return ((Collection) result).iterator();
113 else if (result!=null) {
114 return Collections.singletonList(result).iterator();
121 public Object getComplexRelation(String aMainTablePrefix, List someExtraTables,
122 String aWhereClause, String anOrderByClause, String aDefinition) {
125 new CachingRewindableIterator(
126 new EntityIteratorAdapter(aMainTablePrefix, someExtraTables,
127 aWhereClause, anOrderByClause,
128 -1, getModel(), aDefinition, -1, 0)
131 catch (Throwable t) {
132 throw new RuntimeException(t.getMessage());
137 public List getRelation(String aWhereClause, String anOrderByClause, String aDefinition) {
139 return EntityAdapterEngine.retrieveAdapterList(model, aDefinition, aWhereClause, anOrderByClause, -1, 0);
141 catch (Throwable t) {
142 throw new RuntimeException(t.getMessage());
146 public EntityAdapter getToOneRelation(String aWhereClause, String anOrderByClause, String aDefinition) {
148 Iterator i = new EntityIteratorAdapter(aWhereClause, anOrderByClause, 1, getModel(), aDefinition, 1, 0);
151 return (EntityAdapter) i.next();
154 catch (Throwable t) {
155 throw new RuntimeException(t.getMessage());
159 public EntityAdapter getComplexToOneRelation(String aMainTablePrefix, List someExtraTables,
160 String aWhereClause, String anOrderByClause, String aDefinition) {
162 Iterator i = new EntityIteratorAdapter(aMainTablePrefix, someExtraTables, aWhereClause, anOrderByClause, -1,
163 getModel(), aDefinition, 1, 0);
166 return (EntityAdapter) i.next();
169 catch (Throwable t) {
170 throw new RuntimeException(t.getMessage());