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1
19
20 package org.apache.cayenne.access;
21
22 import java.util.ArrayList  ;
23 import java.util.HashMap ;
24 import java.util.Iterator ;
25 import java.util.List ;
26 import java.util.Map ;
27
28 import org.apache.cayenne.CayenneRuntimeException;
29 import org.apache.cayenne.DataObject;
30 import org.apache.cayenne.DataRow;
31 import org.apache.cayenne.ObjectId;
32 import org.apache.cayenne.PersistenceState;
33 import org.apache.cayenne.Persistent;
34 import org.apache.cayenne.map.DbAttribute;
35 import org.apache.cayenne.map.DbEntity;
36 import org.apache.cayenne.map.EntityInheritanceTree;
37 import org.apache.cayenne.map.ObjEntity;
38 import org.apache.cayenne.reflect.ClassDescriptor;
39
40
46 class ObjectResolver {
47
48 DataContext context;
49 ClassDescriptor descriptor;
50 List primaryKey;
51
52 EntityInheritanceTree inheritanceTree;
53 boolean refreshObjects;
54 boolean resolveInheritance;
55 DataRowStore cache;
56
57 ObjectResolver(DataContext context, ClassDescriptor descriptor, boolean refresh,
58 boolean resolveInheritanceHierarchy) {
59 init(context, descriptor, refresh, resolveInheritanceHierarchy);
60 }
61
62 void init(
63 DataContext context,
64 ClassDescriptor descriptor,
65 boolean refresh,
66 boolean resolveInheritanceHierarchy) {
67 DbEntity dbEntity = descriptor.getEntity().getDbEntity();
69 if (dbEntity == null) {
70 throw new CayenneRuntimeException("ObjEntity '"
71 + descriptor.getEntity().getName()
72 + "' has no DbEntity.");
73 }
74
75 this.primaryKey = dbEntity.getPrimaryKey();
76 if (primaryKey.size() == 0) {
77 throw new CayenneRuntimeException("Won't be able to create ObjectId for '"
78 + descriptor.getEntity().getName()
79 + "'. Reason: DbEntity '"
80 + dbEntity.getName()
81 + "' has no Primary Key defined.");
82 }
83
84 this.context = context;
85 this.cache = context.getObjectStore().getDataRowCache();
86 this.refreshObjects = refresh;
87 this.descriptor = descriptor;
88 this.inheritanceTree = context.getEntityResolver().lookupInheritanceTree(
89 descriptor.getEntity());
90 this.resolveInheritance = (inheritanceTree != null)
91 ? resolveInheritanceHierarchy
92 : false;
93 }
94
95
98 List synchronizedObjectsFromDataRows(List rows) {
99 synchronized (context.getObjectStore()) {
100 return objectsFromDataRows(rows);
101 }
102 }
103
104
111 List objectsFromDataRows(List rows) {
112 if (rows == null || rows.size() == 0) {
113 return new ArrayList (1);
114 }
115
116 List results = new ArrayList (rows.size());
117 Iterator it = rows.iterator();
118
119 while (it.hasNext()) {
120 results.add(objectFromDataRow((DataRow) it.next()));
121 }
122
123 cache.snapshotsUpdatedForObjects(results, rows, refreshObjects);
125
126 return results;
127 }
128
129
139 List relatedObjectsFromDataRows(List rows, PrefetchProcessorNode node) {
140 if (rows == null || rows.size() == 0) {
141 return new ArrayList (1);
142 }
143
144 ObjEntity sourceObjEntity = (ObjEntity) node
145 .getIncoming()
146 .getRelationship()
147 .getSourceEntity();
148 String relatedIdPrefix = node
149 .getIncoming()
150 .getRelationship()
151 .getReverseDbRelationshipPath()
152 + ".";
153
154 List results = new ArrayList (rows.size());
155 Iterator it = rows.iterator();
156
157 while (it.hasNext()) {
158
159 DataRow row = (DataRow) it.next();
160 Persistent object = objectFromDataRow(row);
161 results.add(object);
162
163
165 ObjectId id = createObjectId(row, sourceObjEntity, relatedIdPrefix);
168 Persistent parentObject = (Persistent) context.getObjectStore().getNode(id);
169
170 if (parentObject != null
172 && parentObject.getPersistenceState() != PersistenceState.HOLLOW) {
173 node.linkToParent(object, parentObject);
174 }
175 }
176
177 cache.snapshotsUpdatedForObjects(results, rows, refreshObjects);
179
180 return results;
181 }
182
183
187 Persistent objectFromDataRow(DataRow row) {
188
189 ClassDescriptor classDescriptor;
191
192 if (resolveInheritance) {
193 ObjEntity objectEntity = inheritanceTree.entityMatchingRow(row);
194
195 classDescriptor = (objectEntity != null) ? context
197 .getEntityResolver()
198 .getClassDescriptor(objectEntity.getName()) : descriptor;
199 }
200 else {
201 classDescriptor = descriptor;
202 }
203
204 ObjectId anId = createObjectId(row, classDescriptor.getEntity(), null);
207
208 Persistent object = context.localObject(anId, null);
210
211 int state = object.getPersistenceState();
213 switch (state) {
214 case PersistenceState.COMMITTED:
215 case PersistenceState.MODIFIED:
216 case PersistenceState.DELETED:
217 if (refreshObjects) {
219 DataRowUtils.mergeObjectWithSnapshot(
220 context,
221 classDescriptor,
222 object,
223 row);
224
225 if (object instanceof DataObject) {
226 ((DataObject) object).setSnapshotVersion(row.getVersion());
227 }
228 }
229 break;
230 case PersistenceState.HOLLOW:
231 if (!refreshObjects) {
232 DataRow cachedRow = cache.getCachedSnapshot(anId);
233 if (cachedRow != null) {
234 row = cachedRow;
235 }
236 }
237 DataRowUtils.mergeObjectWithSnapshot(
238 context,
239 classDescriptor,
240 object,
241 row);
242 if (object instanceof DataObject) {
243 ((DataObject) object).setSnapshotVersion(row.getVersion());
244 }
245 break;
246 default:
247 break;
248 }
249
250 return object;
251 }
252
253 ObjEntity getEntity() {
254 return descriptor.getEntity();
255 }
256
257 ClassDescriptor getDescriptor() {
258 return descriptor;
259 }
260
261 ObjectId createObjectId(DataRow dataRow, ObjEntity objEntity, String namePrefix) {
262
263 List pk = objEntity == this.descriptor.getEntity() ? this.primaryKey : objEntity
264 .getDbEntity()
265 .getPrimaryKey();
266
267 boolean prefix = namePrefix != null && namePrefix.length() > 0;
268
269
272 if (pk.size() == 1) {
273 DbAttribute attribute = (DbAttribute) pk.get(0);
274
275 String key = (prefix) ? namePrefix + attribute.getName() : attribute
276 .getName();
277
278 Object val = dataRow.get(key);
279 if (val == null) {
280 throw new CayenneRuntimeException("Null value for '"
281 + key
282 + "'. Snapshot: "
283 + dataRow
284 + ". Prefix: "
285 + namePrefix);
286 }
287
288 return new ObjectId(objEntity.getName(), attribute.getName(), val);
290 }
291
292
294 Map idMap = new HashMap (pk.size() * 2);
295 Iterator it = pk.iterator();
296 while (it.hasNext()) {
297 DbAttribute attribute = (DbAttribute) it.next();
298
299 String key = (prefix) ? namePrefix + attribute.getName() : attribute
300 .getName();
301
302 Object val = dataRow.get(key);
303 if (val == null) {
304 throw new CayenneRuntimeException("Null value for '"
305 + key
306 + "'. Snapshot: "
307 + dataRow
308 + ". Prefix: "
309 + namePrefix);
310 }
311
312 idMap.put(attribute.getName(), val);
314 }
315
316 return new ObjectId(objEntity.getName(), idMap);
317 }
318 }
319 |
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