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1
56
57 package org.objectstyle.cayenne.access.util;
58
59 import java.util.ArrayList  ;
60 import java.util.Collection ;
61 import java.util.Comparator ;
62 import java.util.HashMap ;
63 import java.util.Iterator ;
64 import java.util.List ;
65 import java.util.Map ;
66
67 import org.apache.commons.collections.ComparatorUtils;
68 import org.objectstyle.ashwood.graph.CollectionFactory;
69 import org.objectstyle.ashwood.graph.Digraph;
70 import org.objectstyle.ashwood.graph.GraphUtils;
71 import org.objectstyle.ashwood.graph.IndegreeTopologicalSort;
72 import org.objectstyle.ashwood.graph.MapDigraph;
73 import org.objectstyle.ashwood.graph.StrongConnection;
74 import org.objectstyle.cayenne.CayenneException;
75 import org.objectstyle.cayenne.CayenneRuntimeException;
76 import org.objectstyle.cayenne.DataObject;
77 import org.objectstyle.cayenne.ObjectId;
78 import org.objectstyle.cayenne.access.DataNode;
79 import org.objectstyle.cayenne.access.QueryEngine;
80 import org.objectstyle.cayenne.dba.PkGenerator;
81 import org.objectstyle.cayenne.map.DataMap;
82 import org.objectstyle.cayenne.map.DbAttribute;
83 import org.objectstyle.cayenne.map.DbEntity;
84 import org.objectstyle.cayenne.map.DbJoin;
85 import org.objectstyle.cayenne.map.DbRelationship;
86 import org.objectstyle.cayenne.map.ObjAttribute;
87 import org.objectstyle.cayenne.map.ObjEntity;
88 import org.objectstyle.cayenne.map.ObjRelationship;
89
90
97 public class PrimaryKeyHelper {
98
99 private Map indexedDbEntities;
100 private QueryEngine queryEngine;
101 private DbEntityComparator dbEntityComparator;
102 private ObjEntityComparator objEntityComparator;
103
104 public PrimaryKeyHelper(QueryEngine queryEngine) {
105 this.queryEngine = queryEngine;
106 init();
107 dbEntityComparator = new DbEntityComparator();
108 objEntityComparator = new ObjEntityComparator();
109 }
110
111 public void reset() {
112 init();
113 }
114
115 public Comparator getDbEntityComparator() {
116 return dbEntityComparator;
117 }
118
119 public Comparator getObjEntityComparator() {
120 return objEntityComparator;
121 }
122
123 public void createPermIdsForObjEntity(ObjEntity objEntity, List dataObjects)
124 throws CayenneException {
125
126 if (dataObjects.isEmpty()) {
127 return;
128 }
129
130 DbEntity dbEntity = objEntity.getDbEntity();
131 DataNode owner = queryEngine.lookupDataNode(objEntity.getDataMap());
132 if (owner == null) {
133 throw new CayenneRuntimeException(
134 "No suitable DataNode to handle primary key generation.");
135 }
136
137 PkGenerator pkGenerator = owner.getAdapter().getPkGenerator();
138 boolean supportsGeneratedKeys = owner.getAdapter().supportsGeneratedKeys();
139 List pkAttributes = dbEntity.getPrimaryKey();
140
141 boolean pkFromMaster = true;
142 Iterator i = dataObjects.iterator();
143 while (i.hasNext()) {
144
145 DataObject object = (DataObject) i.next();
146 ObjectId id = object.getObjectId();
147 if (id == null || !id.isTemporary()) {
148 continue;
149 }
150
151 Map idMap = id.getReplacementIdMap();
153
154 if (pkFromMaster) {
156 pkFromMaster = appendPkFromMasterRelationships(
157 idMap,
158 object,
159 objEntity,
160 dbEntity,
161 supportsGeneratedKeys);
162 }
163
164 boolean autoPkDone = false;
165 Iterator it = pkAttributes.iterator();
166 while (it.hasNext()) {
167 DbAttribute dbAttr = (DbAttribute) it.next();
168 String dbAttrName = dbAttr.getName();
169
170 if (supportsGeneratedKeys && dbAttr.isGenerated()) {
172 continue;
173 }
174
175 if (idMap.containsKey(dbAttrName)) {
176 continue;
177 }
178
179 ObjAttribute objAttr = objEntity.getAttributeForDbAttribute(dbAttr);
180 if (objAttr != null) {
181 idMap.put(dbAttrName, object.readPropertyDirectly(objAttr.getName()));
182 continue;
183 }
184
185 if (autoPkDone) {
188 throw new CayenneException(
189 "Primary Key autogeneration only works for a single attribute.");
190 }
191
192 try {
194 Object pkValue = pkGenerator.generatePkForDbEntity(owner, dbEntity);
195 idMap.put(dbAttrName, pkValue);
196 autoPkDone = true;
197 }
198 catch (Exception ex) {
199 throw new CayenneException(
200 "Error generating PK: " + ex.getMessage(),
201 ex);
202 }
203 }
204 }
205 }
206
207 private boolean appendPkFromMasterRelationships(
208 Map idMap,
209 DataObject dataObject,
210 ObjEntity objEntity,
211 DbEntity dbEntity,
212 boolean supportsGeneratedKeys) throws CayenneException {
213
214 boolean useful = false;
215 Iterator it = dbEntity.getRelationships().iterator();
216 while (it.hasNext()) {
217 DbRelationship dbRel = (DbRelationship) it.next();
218 if (!dbRel.isToMasterPK()) {
219 continue;
220 }
221
222 ObjRelationship rel = objEntity.getRelationshipForDbRelationship(dbRel);
223 if (rel == null) {
224 continue;
225 }
226
227 DataObject targetDo = (DataObject) dataObject.readPropertyDirectly(rel
228 .getName());
229
230 if (targetDo == null) {
231 throw new CayenneException(
232 "Null master object, can't create primary key for: "
233 + dataObject.getClass()
234 + "."
235 + dbRel.getName());
236 }
237
238 ObjectId targetKey = targetDo.getObjectId();
239 Map targetKeyMap = targetKey.getIdSnapshot();
240 if (targetKeyMap == null) {
241 throw new CayenneException(noMasterPkMsg(objEntity.getName(), targetKey
242 .getObjectClass()
243 .toString(), dbRel.getName()));
244 }
245
246
251 Iterator joins = dbRel.getJoins().iterator();
252 while (joins.hasNext()) {
253 DbJoin join = (DbJoin) joins.next();
254 Object value = targetKeyMap.get(join.getTargetName());
255 if (value == null) {
256 if (supportsGeneratedKeys && join.getTarget().isGenerated()) {
257 continue;
259 }
260
261 throw new CayenneRuntimeException(
262 "Some parts of FK are missing in snapshot, join: " + join);
263 }
264
265 idMap.put(join.getSourceName(), value);
266 }
267
268 useful = true;
269 }
270
271 return useful;
272 }
273
274 private String noMasterPkMsg(String src, String dst, String rel) {
275 StringBuffer msg = new StringBuffer (
276 "Can't create primary key, master object has no PK snapshot.");
277 msg.append("\nrelationship name: ").append(rel).append(", src object: ").append(
278 src).append(", target obj: ").append(dst);
279 return msg.toString();
280 }
281
282 private List collectAllDbEntities() {
283 List entities = new ArrayList (32);
284 for (Iterator i = queryEngine.getDataMaps().iterator(); i.hasNext();) {
285 entities.addAll(((DataMap) i.next()).getDbEntities());
286 }
287 return entities;
288 }
289
290 private void init() {
291 List dbEntitiesToResolve = collectAllDbEntities();
292 Digraph pkDependencyGraph = new MapDigraph(MapDigraph.HASHMAP_FACTORY);
293 indexedDbEntities = new HashMap (dbEntitiesToResolve.size());
294 for (Iterator i = dbEntitiesToResolve.iterator(); i.hasNext();) {
295 DbEntity origin = (DbEntity) i.next();
296 for (Iterator j = origin.getRelationships().iterator(); j.hasNext();) {
297 DbRelationship relation = (DbRelationship) j.next();
298 if (relation.isToDependentPK()) {
299 DbEntity dst = (DbEntity) relation.getTargetEntity();
300 if (origin.equals(dst)) {
301 continue;
302 }
303 pkDependencyGraph.putArc(origin, dst, Boolean.TRUE);
304 }
305 }
306 }
307 int index = 0;
308 for (Iterator i = dbEntitiesToResolve.iterator(); i.hasNext();) {
309 DbEntity entity = (DbEntity) i.next();
310 if (!pkDependencyGraph.containsVertex(entity)) {
311 indexedDbEntities.put(entity, new Integer (index++));
312 }
313 }
314 boolean acyclic = GraphUtils.isAcyclic(pkDependencyGraph);
315 if (acyclic) {
316 IndegreeTopologicalSort sorter = new IndegreeTopologicalSort(
317 pkDependencyGraph);
318 while (sorter.hasNext())
319 indexedDbEntities.put(sorter.next(), new Integer (index++));
320 }
321 else {
322 StrongConnection contractor = new StrongConnection(
323 pkDependencyGraph,
324 CollectionFactory.ARRAYLIST_FACTORY);
325 Digraph contractedDigraph = new MapDigraph(MapDigraph.HASHMAP_FACTORY);
326 contractor.contract(contractedDigraph, CollectionFactory.ARRAYLIST_FACTORY);
327 IndegreeTopologicalSort sorter = new IndegreeTopologicalSort(
328 contractedDigraph);
329 while (sorter.hasNext()) {
330 Collection component = (Collection ) sorter.next();
331 for (Iterator i = component.iterator(); i.hasNext();)
332 indexedDbEntities.put(i.next(), new Integer (index++));
333 }
334 }
335 }
336
337 private class DbEntityComparator implements Comparator {
338
339 public int compare(Object o1, Object o2) {
340 if (o1.equals(o2)) {
341 return 0;
342 }
343 Integer index1 = (Integer ) indexedDbEntities.get(o1);
344 Integer index2 = (Integer ) indexedDbEntities.get(o2);
345 return ComparatorUtils.NATURAL_COMPARATOR.compare(index1, index2);
346 }
347 }
348
349 private class ObjEntityComparator implements Comparator {
350
351 public int compare(Object o1, Object o2) {
352 if (o1.equals(o2)) {
353 return 0;
354 }
355 DbEntity e1 = ((ObjEntity) o1).getDbEntity();
356 DbEntity e2 = ((ObjEntity) o2).getDbEntity();
357 return dbEntityComparator.compare(e1, e2);
358 }
359 }
360 } |
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