001 package de.deepamehta.core.impl;
002
003 import de.deepamehta.core.AssociationDefinition;
004 import de.deepamehta.core.ChildTopics;
005 import de.deepamehta.core.RelatedTopic;
006 import de.deepamehta.core.Topic;
007 import de.deepamehta.core.model.ChildTopicsModel;
008 import de.deepamehta.core.model.DeepaMehtaObjectModel;
009 import de.deepamehta.core.model.RelatedTopicModel;
010 import de.deepamehta.core.model.SimpleValue;
011 import de.deepamehta.core.model.TopicDeletionModel;
012 import de.deepamehta.core.model.TopicModel;
013 import de.deepamehta.core.model.TopicReferenceModel;
014
015 import java.util.ArrayList;
016 import java.util.HashMap;
017 import java.util.Iterator;
018 import java.util.List;
019 import java.util.Map;
020 import java.util.logging.Logger;
021
022
023
024 /**
025 * A child topics model that is attached to the DB.
026 */
027 class AttachedChildTopics implements ChildTopics {
028
029 // ---------------------------------------------------------------------------------------------- Instance Variables
030
031 private ChildTopicsModel model; // underlying model
032
033 private AttachedDeepaMehtaObject parent; // attached object cache
034
035 /**
036 * Attached object cache.
037 * Key: child type URI (String), value: RelatedTopic or List<RelatedTopic>
038 */
039 private Map<String, Object> childTopics = new HashMap(); // attached object cache
040
041 private EmbeddedService dms;
042
043 private Logger logger = Logger.getLogger(getClass().getName());
044
045 // ---------------------------------------------------------------------------------------------------- Constructors
046
047 AttachedChildTopics(ChildTopicsModel model, AttachedDeepaMehtaObject parent, EmbeddedService dms) {
048 this.model = model;
049 this.parent = parent;
050 this.dms = dms;
051 initAttachedObjectCache();
052 }
053
054 // -------------------------------------------------------------------------------------------------- Public Methods
055
056
057
058 // **********************************
059 // *** ChildTopics Implementation ***
060 // **********************************
061
062
063
064 // === Accessors ===
065
066 @Override
067 public RelatedTopic getTopic(String childTypeUri) {
068 loadChildTopics(childTypeUri);
069 return _getTopic(childTypeUri);
070 }
071
072 @Override
073 public List<RelatedTopic> getTopics(String childTypeUri) {
074 loadChildTopics(childTypeUri);
075 return _getTopics(childTypeUri);
076 }
077
078 // ---
079
080 @Override
081 public Object get(String childTypeUri) {
082 return childTopics.get(childTypeUri);
083 }
084
085 @Override
086 public boolean has(String childTypeUri) {
087 return childTopics.containsKey(childTypeUri);
088 }
089
090 @Override
091 public int size() {
092 return childTopics.size();
093 }
094
095 // ---
096
097 @Override
098 public ChildTopicsModel getModel() {
099 return model;
100 }
101
102
103
104 // === Convenience Accessors ===
105
106 @Override
107 public String getString(String childTypeUri) {
108 return getTopic(childTypeUri).getSimpleValue().toString();
109 }
110
111 @Override
112 public int getInt(String childTypeUri) {
113 return getTopic(childTypeUri).getSimpleValue().intValue();
114 }
115
116 @Override
117 public long getLong(String childTypeUri) {
118 return getTopic(childTypeUri).getSimpleValue().longValue();
119 }
120
121 @Override
122 public double getDouble(String childTypeUri) {
123 return getTopic(childTypeUri).getSimpleValue().doubleValue();
124 }
125
126 @Override
127 public boolean getBoolean(String childTypeUri) {
128 return getTopic(childTypeUri).getSimpleValue().booleanValue();
129 }
130
131 @Override
132 public Object getObject(String childTypeUri) {
133 return getTopic(childTypeUri).getSimpleValue().value();
134 }
135
136 // ---
137
138 @Override
139 public ChildTopics getChildTopics(String childTypeUri) {
140 return getTopic(childTypeUri).getChildTopics();
141 }
142
143 // Note: there are no convenience accessors for a multiple-valued child.
144
145
146
147 // === Manipulators ===
148
149 // --- Single-valued Childs ---
150
151 @Override
152 public ChildTopics set(String childTypeUri, TopicModel value) {
153 return _updateOne(childTypeUri, new RelatedTopicModel(value));
154 }
155
156 // ---
157
158 @Override
159 public ChildTopics set(String childTypeUri, Object value) {
160 return _updateOne(childTypeUri, new RelatedTopicModel(childTypeUri, new SimpleValue(value)));
161 }
162
163 @Override
164 public ChildTopics set(String childTypeUri, ChildTopicsModel value) {
165 return _updateOne(childTypeUri, new RelatedTopicModel(childTypeUri, value));
166 }
167
168 // ---
169
170 @Override
171 public ChildTopics setRef(String childTypeUri, long refTopicId) {
172 return _updateOne(childTypeUri, new TopicReferenceModel(refTopicId));
173 }
174
175 @Override
176 public ChildTopics setRef(String childTypeUri, long refTopicId, ChildTopicsModel relatingAssocChildTopics) {
177 return _updateOne(childTypeUri, new TopicReferenceModel(refTopicId, relatingAssocChildTopics));
178 }
179
180 @Override
181 public ChildTopics setRef(String childTypeUri, String refTopicUri) {
182 return _updateOne(childTypeUri, new TopicReferenceModel(refTopicUri));
183 }
184
185 @Override
186 public ChildTopics setRef(String childTypeUri, String refTopicUri, ChildTopicsModel relatingAssocChildTopics) {
187 return _updateOne(childTypeUri, new TopicReferenceModel(refTopicUri, relatingAssocChildTopics));
188 }
189
190 // ---
191
192 @Override
193 public ChildTopics setDeletionRef(String childTypeUri, long refTopicId) {
194 return _updateOne(childTypeUri, new TopicDeletionModel(refTopicId));
195 }
196
197 @Override
198 public ChildTopics setDeletionRef(String childTypeUri, String refTopicUri) {
199 return _updateOne(childTypeUri, new TopicDeletionModel(refTopicUri));
200 }
201
202 // --- Multiple-valued Childs ---
203
204 @Override
205 public ChildTopics add(String childTypeUri, TopicModel value) {
206 return _updateMany(childTypeUri, new RelatedTopicModel(value));
207 }
208
209 // ---
210
211 @Override
212 public ChildTopics add(String childTypeUri, Object value) {
213 return _updateMany(childTypeUri, new RelatedTopicModel(childTypeUri, new SimpleValue(value)));
214 }
215
216 @Override
217 public ChildTopics add(String childTypeUri, ChildTopicsModel value) {
218 return _updateMany(childTypeUri, new RelatedTopicModel(childTypeUri, value));
219 }
220
221 // ---
222
223 @Override
224 public ChildTopics addRef(String childTypeUri, long refTopicId) {
225 return _updateMany(childTypeUri, new TopicReferenceModel(refTopicId));
226 }
227
228 @Override
229 public ChildTopics addRef(String childTypeUri, long refTopicId, ChildTopicsModel relatingAssocChildTopics) {
230 return _updateMany(childTypeUri, new TopicReferenceModel(refTopicId, relatingAssocChildTopics));
231 }
232
233 @Override
234 public ChildTopics addRef(String childTypeUri, String refTopicUri) {
235 return _updateMany(childTypeUri, new TopicReferenceModel(refTopicUri));
236 }
237
238 @Override
239 public ChildTopics addRef(String childTypeUri, String refTopicUri, ChildTopicsModel relatingAssocChildTopics) {
240 return _updateMany(childTypeUri, new TopicReferenceModel(refTopicUri, relatingAssocChildTopics));
241 }
242
243 // ---
244
245 @Override
246 public ChildTopics addDeletionRef(String childTypeUri, long refTopicId) {
247 return _updateMany(childTypeUri, new TopicDeletionModel(refTopicId));
248 }
249
250 @Override
251 public ChildTopics addDeletionRef(String childTypeUri, String refTopicUri) {
252 return _updateMany(childTypeUri, new TopicDeletionModel(refTopicUri));
253 }
254
255
256
257 // === Iterable Implementation ===
258
259 @Override
260 public Iterator<String> iterator() {
261 return childTopics.keySet().iterator();
262 }
263
264
265
266 // ----------------------------------------------------------------------------------------- Package Private Methods
267
268 void update(ChildTopicsModel newComp) {
269 try {
270 for (AssociationDefinition assocDef : parent.getType().getAssocDefs()) {
271 String childTypeUri = assocDef.getChildTypeUri();
272 String cardinalityUri = assocDef.getChildCardinalityUri();
273 RelatedTopicModel newChildTopic = null; // only used for "one"
274 List<RelatedTopicModel> newChildTopics = null; // only used for "many"
275 if (cardinalityUri.equals("dm4.core.one")) {
276 newChildTopic = newComp.getTopic(childTypeUri, null); // defaultValue=null
277 // skip if not contained in update request
278 if (newChildTopic == null) {
279 continue;
280 }
281 } else if (cardinalityUri.equals("dm4.core.many")) {
282 newChildTopics = newComp.getTopics(childTypeUri, null); // defaultValue=null
283 // skip if not contained in update request
284 if (newChildTopics == null) {
285 continue;
286 }
287 } else {
288 throw new RuntimeException("\"" + cardinalityUri + "\" is an unexpected cardinality URI");
289 }
290 //
291 updateChildTopics(newChildTopic, newChildTopics, assocDef);
292 }
293 //
294 refreshParentLabel();
295 //
296 } catch (Exception e) {
297 throw new RuntimeException("Updating the child topics of " + parent.className() + " " + parent.getId() +
298 " failed (newComp=" + newComp + ")", e);
299 }
300 }
301
302 // Note: the given association definition must not necessarily originate from the parent object's type definition.
303 // It may originate from a facet definition as well.
304 // Called from AttachedDeepaMehtaObject.updateChildTopic() and AttachedDeepaMehtaObject.updateChildTopics().
305 void updateChildTopics(RelatedTopicModel newChildTopic, List<RelatedTopicModel> newChildTopics,
306 AssociationDefinition assocDef) {
307 // Note: updating the child topics requires them to be loaded
308 loadChildTopics(assocDef);
309 //
310 String assocTypeUri = assocDef.getTypeUri();
311 boolean one = newChildTopic != null;
312 if (assocTypeUri.equals("dm4.core.composition_def")) {
313 if (one) {
314 updateCompositionOne(newChildTopic, assocDef);
315 } else {
316 updateCompositionMany(newChildTopics, assocDef);
317 }
318 } else if (assocTypeUri.equals("dm4.core.aggregation_def")) {
319 if (one) {
320 updateAggregationOne(newChildTopic, assocDef);
321 } else {
322 updateAggregationMany(newChildTopics, assocDef);
323 }
324 } else {
325 throw new RuntimeException("Association type \"" + assocTypeUri + "\" not supported");
326 }
327 }
328
329 // ---
330
331 void loadChildTopics() {
332 for (AssociationDefinition assocDef : parent.getType().getAssocDefs()) {
333 loadChildTopics(assocDef);
334 }
335 }
336
337 void loadChildTopics(String childTypeUri) {
338 loadChildTopics(getAssocDef(childTypeUri));
339 }
340
341
342
343 // ------------------------------------------------------------------------------------------------- Private Methods
344
345 /**
346 * Recursively loads child topics (model) and updates this attached object cache accordingly.
347 * If the child topics are loaded already nothing is performed.
348 *
349 * @param assocDef the child topics according to this association definition are loaded.
350 * <p>
351 * Note: the association definition must not necessarily originate from the parent object's
352 * type definition. It may originate from a facet definition as well.
353 */
354 private void loadChildTopics(AssociationDefinition assocDef) {
355 String childTypeUri = assocDef.getChildTypeUri();
356 if (!has(childTypeUri)) {
357 logger.fine("### Lazy-loading \"" + childTypeUri + "\" child topic(s) of " + parent.className() + " " +
358 parent.getId());
359 dms.valueStorage.fetchChildTopics(parent.getModel(), assocDef.getModel());
360 initAttachedObjectCache(childTypeUri);
361 }
362 }
363
364 private void refreshParentLabel() {
365 DeepaMehtaObjectModel parent = this.parent.getModel();
366 //
367 for (String childTypeUri : dms.valueStorage.getLabelChildTypeUris(parent)) {
368 loadChildTopics(childTypeUri);
369 }
370 //
371 dms.valueStorage.refreshLabel(parent);
372 }
373
374 // ---
375
376 // Note 1: we need to explicitly declare the arg as RelatedTopicModel. When declared as TopicModel instead the
377 // JVM would invoke the ChildTopicsModel's put()/add() which takes a TopicModel object even if at runtime a
378 // RelatedTopicModel or even a TopicReferenceModel is passed. This is because Java method overloading involves
379 // no dynamic dispatch. See the methodOverloading tests in JavaAPITest.java (in module dm4-test).
380
381 // Note 2: calling parent.update(..) would not work. The JVM would call the update() method of the base class
382 // (AttachedDeepaMehtaObject), not the subclass's update() method. This is related to Java's (missing) multiple
383 // dispatch. Note that 2 inheritance hierarchies are involved here: the DM object hierarchy and the DM model
384 // hierarchy. See the missingMultipleDispatch tests in JavaAPITest.java (in module dm4-test).
385
386 private ChildTopics _updateOne(String childTypeUri, RelatedTopicModel newChildTopic) {
387 parent.updateChildTopics(new ChildTopicsModel().put(childTypeUri, newChildTopic));
388 return this;
389 }
390
391 private ChildTopics _updateMany(String childTypeUri, RelatedTopicModel newChildTopic) {
392 parent.updateChildTopics(new ChildTopicsModel().add(childTypeUri, newChildTopic));
393 return this;
394 }
395
396
397
398 // === Update Child Topics ===
399
400 // --- Composition ---
401
402 private void updateCompositionOne(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
403 RelatedTopic childTopic = _getTopic(assocDef.getChildTypeUri(), null);
404 // Note: for cardinality one the simple request format is sufficient. The child's topic ID is not required.
405 // ### TODO: possibly sanity check: if child's topic ID *is* provided it must match with the fetched topic.
406 if (newChildTopic instanceof TopicDeletionModel) {
407 deleteChildTopicOne(childTopic, assocDef, true); // deleteChild=true
408 } else if (newChildTopic instanceof TopicReferenceModel) {
409 createAssignmentOne(childTopic, (TopicReferenceModel) newChildTopic, assocDef, true); // deleteChild=true
410 } else if (childTopic != null) {
411 updateRelatedTopic(childTopic, newChildTopic);
412 } else {
413 createChildTopicOne(newChildTopic, assocDef);
414 }
415 }
416
417 private void updateCompositionMany(List<RelatedTopicModel> newChildTopics, AssociationDefinition assocDef) {
418 for (RelatedTopicModel newChildTopic : newChildTopics) {
419 long childTopicId = newChildTopic.getId();
420 if (newChildTopic instanceof TopicDeletionModel) {
421 deleteChildTopicMany(childTopicId, assocDef, true); // deleteChild=true
422 } else if (newChildTopic instanceof TopicReferenceModel) {
423 createAssignmentMany((TopicReferenceModel) newChildTopic, assocDef);
424 } else if (childTopicId != -1) {
425 updateChildTopicMany(newChildTopic, assocDef);
426 } else {
427 createChildTopicMany(newChildTopic, assocDef);
428 }
429 }
430 }
431
432 // --- Aggregation ---
433
434 private void updateAggregationOne(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
435 RelatedTopic childTopic = _getTopic(assocDef.getChildTypeUri(), null);
436 // ### TODO: possibly sanity check: if child's topic ID *is* provided it must match with the fetched topic.
437 if (newChildTopic instanceof TopicDeletionModel) {
438 deleteChildTopicOne(childTopic, assocDef, false); // deleteChild=false
439 } else if (newChildTopic instanceof TopicReferenceModel) {
440 createAssignmentOne(childTopic, (TopicReferenceModel) newChildTopic, assocDef, false); // deleteChild=false
441 } else if (newChildTopic.getId() != -1) {
442 updateChildTopicOne(newChildTopic, assocDef);
443 } else {
444 if (childTopic != null) {
445 childTopic.getRelatingAssociation().delete();
446 }
447 createChildTopicOne(newChildTopic, assocDef);
448 }
449 }
450
451 private void updateAggregationMany(List<RelatedTopicModel> newChildTopics, AssociationDefinition assocDef) {
452 for (RelatedTopicModel newChildTopic : newChildTopics) {
453 long childTopicId = newChildTopic.getId();
454 if (newChildTopic instanceof TopicDeletionModel) {
455 deleteChildTopicMany(childTopicId, assocDef, false); // deleteChild=false
456 } else if (newChildTopic instanceof TopicReferenceModel) {
457 createAssignmentMany((TopicReferenceModel) newChildTopic, assocDef);
458 } else if (childTopicId != -1) {
459 updateChildTopicMany(newChildTopic, assocDef);
460 } else {
461 createChildTopicMany(newChildTopic, assocDef);
462 }
463 }
464 }
465
466 // --- Update ---
467
468 private void updateChildTopicOne(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
469 RelatedTopic childTopic = _getTopic(assocDef.getChildTypeUri(), null);
470 //
471 if (childTopic == null || childTopic.getId() != newChildTopic.getId()) {
472 throw new RuntimeException("Topic " + newChildTopic.getId() + " is not a child of " +
473 parent.className() + " " + parent.getId() + " according to " + assocDef);
474 }
475 //
476 updateRelatedTopic(childTopic, newChildTopic);
477 // Note: memory is already up-to-date. The child topic is updated in-place of parent.
478 }
479
480 private void updateChildTopicMany(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
481 RelatedTopic childTopic = findChildTopicById(newChildTopic.getId(), assocDef);
482 //
483 if (childTopic == null) {
484 throw new RuntimeException("Topic " + newChildTopic.getId() + " is not a child of " +
485 parent.className() + " " + parent.getId() + " according to " + assocDef);
486 }
487 //
488 updateRelatedTopic(childTopic, newChildTopic);
489 // Note: memory is already up-to-date. The child topic is updated in-place of parent.
490 }
491
492 // ---
493
494 private void updateRelatedTopic(RelatedTopic childTopic, RelatedTopicModel newChildTopic) {
495 // update topic
496 ((AttachedTopic) childTopic)._update(newChildTopic);
497 // update association
498 updateRelatingAssociation(childTopic, newChildTopic);
499 }
500
501 private void updateRelatingAssociation(RelatedTopic childTopic, RelatedTopicModel newChildTopic) {
502 childTopic.getRelatingAssociation().update(newChildTopic.getRelatingAssociation());
503 }
504
505 // --- Create ---
506
507 private void createChildTopicOne(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
508 // update DB
509 RelatedTopic childTopic = createAndAssociateChildTopic(newChildTopic, assocDef);
510 // update memory
511 putInChildTopics(childTopic, assocDef);
512 }
513
514 private void createChildTopicMany(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
515 // update DB
516 RelatedTopic childTopic = createAndAssociateChildTopic(newChildTopic, assocDef);
517 // update memory
518 addToChildTopics(childTopic, assocDef);
519 }
520
521 // ---
522
523 private RelatedTopic createAndAssociateChildTopic(RelatedTopicModel childTopic, AssociationDefinition assocDef) {
524 dms.createTopic(childTopic);
525 return associateChildTopic(childTopic, assocDef);
526 }
527
528 // --- Assignment ---
529
530 private void createAssignmentOne(RelatedTopic childTopic, TopicReferenceModel newChildTopic,
531 AssociationDefinition assocDef, boolean deleteChildTopic) {
532 if (childTopic != null) {
533 if (newChildTopic.isReferingTo(childTopic)) {
534 updateRelatingAssociation(childTopic, newChildTopic);
535 // Note: memory is already up-to-date. The association is updated in-place of parent.
536 return;
537 }
538 if (deleteChildTopic) {
539 childTopic.delete();
540 } else {
541 childTopic.getRelatingAssociation().delete();
542 }
543 }
544 // update DB
545 RelatedTopic topic = resolveRefAndAssociateChildTopic(newChildTopic, assocDef);
546 // update memory
547 putInChildTopics(topic, assocDef);
548 }
549
550 private void createAssignmentMany(TopicReferenceModel newChildTopic, AssociationDefinition assocDef) {
551 RelatedTopic childTopic = findChildTopicByRef(newChildTopic, assocDef);
552 if (childTopic != null) {
553 // Note: "create assignment" is an idempotent operation. A create request for an assignment which
554 // exists already is not an error. Instead, nothing is performed.
555 updateRelatingAssociation(childTopic, newChildTopic);
556 // Note: memory is already up-to-date. The association is updated in-place of parent.
557 return;
558 }
559 // update DB
560 RelatedTopic topic = resolveRefAndAssociateChildTopic(newChildTopic, assocDef);
561 // update memory
562 addToChildTopics(topic, assocDef);
563 }
564
565 // ---
566
567 /**
568 * Creates an association between our parent object ("Parent" role) and the referenced topic ("Child" role).
569 * The association type is taken from the given association definition.
570 *
571 * @return the resolved child topic.
572 */
573 RelatedTopic resolveRefAndAssociateChildTopic(TopicReferenceModel childTopicRef, AssociationDefinition assocDef) {
574 dms.valueStorage.resolveReference(childTopicRef);
575 return associateChildTopic(childTopicRef, assocDef);
576 }
577
578 private RelatedTopic associateChildTopic(RelatedTopicModel childTopic, AssociationDefinition assocDef) {
579 dms.valueStorage.associateChildTopic(parent.getModel(), childTopic, assocDef.getModel());
580 return instantiateRelatedTopic(childTopic);
581 }
582
583 // --- Delete ---
584
585 private void deleteChildTopicOne(RelatedTopic childTopic, AssociationDefinition assocDef,
586 boolean deleteChildTopic) {
587 if (childTopic == null) {
588 // Note: "delete child"/"delete assignment" is an idempotent operation. A delete request for a
589 // child/assignment which has been deleted already (resp. is non-existing) is not an error.
590 // Instead, nothing is performed.
591 return;
592 }
593 // update DB
594 if (deleteChildTopic) {
595 childTopic.delete();
596 } else {
597 childTopic.getRelatingAssociation().delete();
598 }
599 // update memory
600 removeChildTopic(assocDef);
601 }
602
603 private void deleteChildTopicMany(long childTopicId, AssociationDefinition assocDef, boolean deleteChildTopic) {
604 RelatedTopic childTopic = findChildTopicById(childTopicId, assocDef);
605 if (childTopic == null) {
606 // Note: "delete child"/"delete assignment" is an idempotent operation. A delete request for a
607 // child/assignment which has been deleted already (resp. is non-existing) is not an error.
608 // Instead, nothing is performed.
609 return;
610 }
611 // update DB
612 if (deleteChildTopic) {
613 childTopic.delete();
614 } else {
615 childTopic.getRelatingAssociation().delete();
616 }
617 // update memory
618 removeFromChildTopics(childTopic, assocDef);
619 }
620
621
622
623 // === Attached Object Cache ===
624
625 // --- Access ---
626
627 private RelatedTopic _getTopic(String childTypeUri) {
628 RelatedTopic topic = (RelatedTopic) childTopics.get(childTypeUri);
629 // error check
630 if (topic == null) {
631 throw new RuntimeException("Child topic of type \"" + childTypeUri + "\" not found in " + childTopics);
632 }
633 //
634 return topic;
635 }
636
637 private RelatedTopic _getTopic(String childTypeUri, RelatedTopic defaultTopic) {
638 RelatedTopic topic = (RelatedTopic) childTopics.get(childTypeUri);
639 return topic != null ? topic : defaultTopic;
640 }
641
642 // ---
643
644 private List<RelatedTopic> _getTopics(String childTypeUri) {
645 try {
646 List<RelatedTopic> topics = (List<RelatedTopic>) childTopics.get(childTypeUri);
647 // error check
648 if (topics == null) {
649 throw new RuntimeException("Child topics of type \"" + childTypeUri + "\" not found in " + childTopics);
650 }
651 //
652 return topics;
653 } catch (ClassCastException e) {
654 getModel().throwInvalidAccess(childTypeUri, e);
655 return null; // never reached
656 }
657 }
658
659 private List<RelatedTopic> _getTopics(String childTypeUri, List<RelatedTopic> defaultValue) {
660 try {
661 List<RelatedTopic> topics = (List<RelatedTopic>) childTopics.get(childTypeUri);
662 return topics != null ? topics : defaultValue;
663 } catch (ClassCastException e) {
664 getModel().throwInvalidAccess(childTypeUri, e);
665 return null; // never reached
666 }
667 }
668
669 // ---
670
671 /**
672 * For multiple-valued childs: looks in the attached object cache for a child topic by ID.
673 */
674 private RelatedTopic findChildTopicById(long childTopicId, AssociationDefinition assocDef) {
675 List<RelatedTopic> childTopics = _getTopics(assocDef.getChildTypeUri(), new ArrayList());
676 for (RelatedTopic childTopic : childTopics) {
677 if (childTopic.getId() == childTopicId) {
678 return childTopic;
679 }
680 }
681 return null;
682 }
683
684 /**
685 * For multiple-valued childs: looks in the attached object cache for the child topic the given reference refers to.
686 *
687 * @param assocDef the child topics according to this association definition are considered.
688 */
689 private RelatedTopic findChildTopicByRef(TopicReferenceModel topicRef, AssociationDefinition assocDef) {
690 return topicRef.findReferencedTopic(_getTopics(assocDef.getChildTypeUri(), new ArrayList()));
691 }
692
693 // ---
694
695 private AssociationDefinition getAssocDef(String childTypeUri) {
696 // Note: doesn't work for facets
697 return parent.getType().getAssocDef(childTypeUri);
698 }
699
700 // --- Update attached object cache + underlying model ---
701
702 /**
703 * For single-valued childs
704 */
705 private void putInChildTopics(RelatedTopic childTopic, AssociationDefinition assocDef) {
706 String childTypeUri = assocDef.getChildTypeUri();
707 put(childTypeUri, childTopic); // attached object cache
708 getModel().put(childTypeUri, childTopic.getModel()); // underlying model
709 }
710
711 /**
712 * For single-valued childs
713 */
714 private void removeChildTopic(AssociationDefinition assocDef) {
715 String childTypeUri = assocDef.getChildTypeUri();
716 remove(childTypeUri); // attached object cache
717 getModel().remove(childTypeUri); // underlying model
718 }
719
720 /**
721 * For multiple-valued childs
722 */
723 private void addToChildTopics(RelatedTopic childTopic, AssociationDefinition assocDef) {
724 String childTypeUri = assocDef.getChildTypeUri();
725 add(childTypeUri, childTopic); // attached object cache
726 getModel().add(childTypeUri, childTopic.getModel()); // underlying model
727 }
728
729 /**
730 * For multiple-valued childs
731 */
732 private void removeFromChildTopics(Topic childTopic, AssociationDefinition assocDef) {
733 String childTypeUri = assocDef.getChildTypeUri();
734 remove(childTypeUri, childTopic); // attached object cache
735 getModel().remove(childTypeUri, childTopic.getModel()); // underlying model
736 }
737
738 // --- Update attached object cache ---
739
740 /**
741 * Puts a single-valued child. An existing value is overwritten.
742 */
743 private void put(String childTypeUri, Topic topic) {
744 childTopics.put(childTypeUri, topic);
745 }
746
747 /**
748 * Removes a single-valued child.
749 */
750 private void remove(String childTypeUri) {
751 childTopics.remove(childTypeUri);
752 }
753
754 /**
755 * Adds a value to a multiple-valued child.
756 */
757 private void add(String childTypeUri, RelatedTopic topic) {
758 List<RelatedTopic> topics = _getTopics(childTypeUri, null); // defaultValue=null
759 // Note: topics just created have no child topics yet
760 if (topics == null) {
761 topics = new ArrayList();
762 childTopics.put(childTypeUri, topics);
763 }
764 topics.add(topic);
765 }
766
767 /**
768 * Removes a value from a multiple-valued child.
769 */
770 private void remove(String childTypeUri, Topic topic) {
771 List<RelatedTopic> topics = _getTopics(childTypeUri, null); // defaultValue=null
772 if (topics != null) {
773 topics.remove(topic);
774 }
775 }
776
777 // --- Initialization ---
778
779 /**
780 * Initializes this attached object cache. Creates a hierarchy of attached topics (recursively) that is isomorph
781 * to the underlying model.
782 */
783 private void initAttachedObjectCache() {
784 for (String childTypeUri : model) {
785 initAttachedObjectCache(childTypeUri);
786 }
787 }
788
789 /**
790 * Initializes this attached object cache selectively. Creates a hierarchy of attached topics (recursively) that is
791 * isomorph to the underlying model, starting at the given child sub-tree.
792 */
793 private void initAttachedObjectCache(String childTypeUri) {
794 Object value = model.get(childTypeUri);
795 // Note: topics just created have no child topics yet
796 if (value == null) {
797 return;
798 }
799 // Note: no direct recursion takes place here. Recursion is indirect: attached topics are created here, this
800 // implies creating further AttachedChildTopics objects, which in turn calls this method again but for the next
801 // child-level. Finally attached topics are created for all child-levels.
802 if (value instanceof RelatedTopicModel) {
803 RelatedTopicModel childTopic = (RelatedTopicModel) value;
804 childTopics.put(childTypeUri, instantiateRelatedTopic(childTopic));
805 } else if (value instanceof List) {
806 List<RelatedTopic> topics = new ArrayList();
807 childTopics.put(childTypeUri, topics);
808 for (RelatedTopicModel childTopic : (List<RelatedTopicModel>) value) {
809 topics.add(instantiateRelatedTopic(childTopic));
810 }
811 } else {
812 throw new RuntimeException("Unexpected value in a ChildTopicsModel: " + value);
813 }
814 }
815
816 /**
817 * Creates an attached topic to be put in this attached object cache.
818 */
819 private RelatedTopic instantiateRelatedTopic(RelatedTopicModel model) {
820 try {
821 return new AttachedRelatedTopic(model, dms);
822 } catch (Exception e) {
823 throw new RuntimeException("RelatedTopic instantiation failed (" + model + ")", e);
824 }
825 }
826 }