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1
56 package org.objectstyle.cayenne.access;
57
58 import java.util.Collection  ;
59 import java.util.HashMap ;
60 import java.util.Iterator ;
61 import java.util.Map ;
62
63 import org.apache.commons.collections.Factory;
64 import org.apache.commons.collections.Transformer;
65 import org.objectstyle.cayenne.CayenneRuntimeException;
66 import org.objectstyle.cayenne.DataObject;
67 import org.objectstyle.cayenne.ObjectId;
68 import org.objectstyle.cayenne.dba.PkGenerator;
69 import org.objectstyle.cayenne.map.DbEntity;
70 import org.objectstyle.cayenne.map.ObjEntity;
71
72
80 class EntityDescriptor {
81
82 DataNode node;
83 ObjEntity entity;
84 DbEntity dbEntity;
85 Map snapshotTransformers;
86
87 EntityDescriptor(DataNode node, ObjEntity entity) {
88 this.node = node;
89 this.entity = entity;
90 this.dbEntity = entity.getDbEntity();
91 initTransformers();
92 }
93
94 private void initTransformers() {
95
96 Collection attributes = dbEntity.getAttributes();
97 this.snapshotTransformers = new HashMap ((int) (attributes.size() * 4.00 / 3.00));
98
99
101 Iterator it = entity.getAttributes().iterator();
102 while (it.hasNext()) {
103
105 }
106 }
107
108
113 Map deferredSnapshot(DataObject object) {
114 Map snapshot = new HashMap ((int) (snapshotTransformers.size() * 4.00 / 3.00));
115 Iterator it = snapshotTransformers.entrySet().iterator();
116 while (it.hasNext()) {
117 Map.Entry entry = (Map.Entry ) it.next();
118 snapshot.put(entry.getKey(), ((Transformer) entry.getValue())
119 .transform(object));
120 }
121
122 return snapshot;
123 }
124
125 Object deferredSnapshotValue(DataObject object, String dbAttributeName) {
126 Transformer transformer = (Transformer) snapshotTransformers
127 .get(dbAttributeName);
128
129 if (transformer == null) {
130 throw new CayenneRuntimeException("Invalid DbAttribute: " + dbAttributeName);
131 }
132
133 return transformer.transform(object);
134 }
135
136
140 abstract class DataObjectTransformer implements Transformer {
141
142 public Object transform(Object input) {
143 if (input instanceof DataObject) {
144 return (DataObject) transformDataObject((DataObject) input);
145 }
146
147 throw new CayenneRuntimeException("Invalid input: " + input);
148 }
149
150 protected abstract Object transformDataObject(DataObject object);
151 }
152
153 final class NullPredicateTransformer extends DataObjectTransformer {
155
156 String attributeName;
157 DataObjectTransformer[] transformers;
158
159 NullPredicateTransformer(DataObjectTransformer[] transformers,
160 String attributeName) {
161 this.transformers = transformers;
162 this.attributeName = attributeName;
163 }
164
165 protected Object transformDataObject(DataObject object) {
166 for (int i = 0; i < transformers.length; i++) {
167 Object value = transformers[i].transformDataObject(object);
168 if (value != null) {
169 return value;
170 }
171 }
172
173 throw new CayenneRuntimeException("Problem getting snapshot value for "
174 + object.getClass()
175 + ", attribute name: "
176 + attributeName);
177 }
178 }
179
180 final class ObjectPropertyTransformer extends DataObjectTransformer {
181
182 String property;
183
184 ObjectPropertyTransformer(String property) {
185 this.property = property;
186 }
187
188 protected Object transformDataObject(DataObject object) {
189 return object.readPropertyDirectly(property);
190 }
191 }
192
193 final class PropagatedValueTransformer extends DataObjectTransformer {
194
195 String masterProperty;
196 String masterIDKey;
197 boolean deferred;
198 boolean required;
199
200 PropagatedValueTransformer(String masterProperty, String masterIDKey,
201 boolean required, boolean deferred) {
202 this.masterIDKey = masterIDKey;
203 this.masterProperty = masterProperty;
204 this.required = required;
205 this.deferred = deferred;
206 }
207
208 protected Object transformDataObject(DataObject object) {
209
210 DataObject targetDo = (DataObject) object
211 .readPropertyDirectly(masterProperty);
212
213 if (targetDo == null) {
214 throw new CayenneRuntimeException(
215 "Problem extracting master PK value - null master object for "
216 + object.getClass()
217 + "."
218 + masterProperty);
219 }
220
221 ObjectId targetKey = targetDo.getObjectId();
222
223 if (deferred) {
224 return new DeferredIDValueFactory(targetKey, masterIDKey);
225 }
226
227 Object value = targetKey.getValueForAttribute(masterIDKey);
228
229 if (required && value == null) {
230 throw new CayenneRuntimeException(
231 "Problem extracting master PK value - null master PK "
232 + object.getClass()
233 + "."
234 + masterProperty);
235 }
236
237 return value;
238 }
239 }
240
241 final class CayenneGeneratedPKTransformer extends DataObjectTransformer {
242
243 PkGenerator generator;
244
245 CayenneGeneratedPKTransformer(PkGenerator generator) {
246 this.generator = generator;
247 }
248
249 protected Object transformDataObject(DataObject object) {
250 try {
251 return generator.generatePkForDbEntity(node, dbEntity);
252 }
253 catch (Exception ex) {
254 throw new CayenneRuntimeException("Error generating PK: "
255 + ex.getMessage(), ex);
256 }
257 }
258 }
259
260
264 final static class DeferredIDValueFactory implements Factory {
265
266 ObjectId objectID;
267 String idKey;
268
269 DeferredIDValueFactory(ObjectId objectID, String idKey) {
270 this.objectID = objectID;
271 this.idKey = idKey;
272 }
273
274 public Object create() {
275 if (!objectID.isReplacementIdAttached()) {
276 throw new CayenneRuntimeException("Replacement value for key '"
277 + idKey
278 + "' is not available in ObjectId "
279 + objectID);
280 }
281
282 Map replacementId = objectID.getReplacementIdMap();
283 Object value = replacementId.get(idKey);
284 if (value == null) {
285 throw new CayenneRuntimeException("Replacement value for key '"
286 + idKey
287 + "' is not available in ObjectId "
288 + objectID);
289 }
290
291 return value;
292 }
293 }
294 } |
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