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[simantics/platform.git] / bundles / org.simantics.graph.db / src / org / simantics / graph / db / StreamingTransferableGraphImportProcess.java
1 /*******************************************************************************
2  * Copyright (c) 2012, 2017 Association for Decentralized Information Management
3  * in Industry THTH ry.
4  * All rights reserved. This program and the accompanying materials
5  * are made available under the terms of the Eclipse Public License v1.0
6  * which accompanies this distribution, and is available at
7  * http://www.eclipse.org/legal/epl-v10.html
8  *
9  * Contributors:
10  *     VTT Technical Research Centre of Finland - initial API and implementation
11  *     Semantum Oy - e.g. #7016
12  *******************************************************************************/
13 package org.simantics.graph.db;
14
15 import java.io.DataInput;
16 import java.io.IOException;
17 import java.io.InputStream;
18 import java.util.ArrayList;
19 import java.util.Collections;
20 import java.util.HashMap;
21 import java.util.HashSet;
22 import java.util.Map;
23 import java.util.Set;
24 import java.util.TreeMap;
25
26 import org.simantics.databoard.Bindings;
27 import org.simantics.databoard.adapter.AdaptException;
28 import org.simantics.databoard.binding.Binding;
29 import org.simantics.databoard.binding.mutable.Variant;
30 import org.simantics.databoard.serialization.Serializer;
31 import org.simantics.databoard.type.Datatype;
32 import org.simantics.databoard.util.URIStringUtils;
33 import org.simantics.db.ReadGraph;
34 import org.simantics.db.Resource;
35 import org.simantics.db.Session;
36 import org.simantics.db.VirtualGraph;
37 import org.simantics.db.WriteOnlyGraph;
38 import org.simantics.db.common.WriteBindings;
39 import org.simantics.db.common.procedure.adapter.TransientCacheAsyncListener;
40 import org.simantics.db.common.request.PossibleIndexRoot;
41 import org.simantics.db.common.uri.UnescapedChildMapOfResource;
42 import org.simantics.db.common.utils.Logger;
43 import org.simantics.db.exception.DatabaseException;
44 import org.simantics.db.service.ClusterBuilder2;
45 import org.simantics.db.service.ClusterBuilderFactory;
46 import org.simantics.db.service.ClusteringSupport;
47 import org.simantics.db.service.SerialisationSupport;
48 import org.simantics.db.service.XSupport;
49 import org.simantics.graph.db.TransferableGraphSource.TransferableGraphSourceProcedure;
50 import org.simantics.graph.db.TransferableGraphSource.TransferableGraphSourceValueProcedure;
51 import org.simantics.graph.representation.Extensions;
52 import org.simantics.graph.representation.External;
53 import org.simantics.graph.representation.Identity;
54 import org.simantics.graph.representation.IdentityDefinition;
55 import org.simantics.graph.representation.Internal;
56 import org.simantics.graph.representation.Optional;
57 import org.simantics.graph.representation.Root;
58 import org.simantics.graph.representation.TransferableGraphUtils;
59 import org.simantics.graph.utils.TGResourceUtil;
60 import org.simantics.graph.utils.TGResourceUtil.LongAdapter;
61 import org.simantics.utils.datastructures.Pair;
62 import org.slf4j.LoggerFactory;
63
64 import gnu.trove.map.TIntObjectMap;
65 import gnu.trove.map.hash.TIntObjectHashMap;
66
67 public class StreamingTransferableGraphImportProcess implements TransferableGraphImporter {
68
69         private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(StreamingTransferableGraphImportProcess.class);
70
71         Resource indexRoot;
72         TransferableGraphSource tg;
73         VirtualGraph vg;
74         IImportAdvisor2 advisor;
75         TGStatusMonitor monitor;
76         ClusterBuilder2 builder;
77         final TGResourceUtil resourceUtil = new TGResourceUtil();
78
79         int[] handles;
80
81         Map<String,Integer> allMissingExternals = new HashMap<>();
82         Set<String> missingExternals = new HashSet<>();
83         Map<String,Resource> resolvedParents = new HashMap<>();
84         TIntObjectHashMap<Resource> existingInternalMap = new TIntObjectHashMap<>();
85
86         int resourceCount;
87         Identity[] identities;
88         TreeMap<String, Variant> extensions;
89
90         // Builtins
91         Resource RootLibrary;
92         Resource String;
93         Resource ExternalEntity;
94         Resource Library;
95
96         Resource InstanceOf;
97         Resource ConsistsOf;
98         Resource PartOf;
99         Resource HasName;
100         Resource NameOf;        
101
102         public StreamingTransferableGraphImportProcess(Session session, VirtualGraph vg, TransferableGraphSource tg, IImportAdvisor2 advisor) {
103                 this(session, vg, tg, advisor, null);
104         }
105
106         public StreamingTransferableGraphImportProcess(Session session, VirtualGraph vg, TransferableGraphSource tg, IImportAdvisor2 advisor, TGStatusMonitor monitor) {
107                 this.tg = tg;
108                 this.vg = vg;
109                 this.advisor = advisor;
110                 this.monitor = monitor;
111         }
112
113         private int updatePercentage(int percentage, int done, int total) {
114                 if (monitor != null && (done & 63) == 0) {
115                         int current = 100*done / total;
116                         if (current > percentage) {
117                                 percentage = current;
118                                 monitor.status(percentage);
119                         }
120                 }
121                 return percentage;
122         }
123
124         public void readIdentities(ReadGraph g) throws Exception {
125                 extensions = tg.getExtensions();
126                 resourceCount = tg.getResourceCount();
127                 identities = new Identity[tg.getIdentityCount()];
128                 tg.forIdentities(g, new TransferableGraphSourceProcedure<Identity>() {
129                         
130                         int counter = 0;
131                         
132                         @Override
133                         public void execute(Identity value) throws Exception {
134                                 identities[counter++] = value;
135                         }
136                 });
137         }
138
139         public void findBuiltins(WriteOnlyGraph g) throws DatabaseException {
140                 RootLibrary = g.getBuiltin("http:/");
141                 String = g.getBuiltin(CoreInitialization.LAYER0 + "String");
142                 Library = g.getBuiltin(CoreInitialization.LAYER0 + "Library");
143                 InstanceOf = g.getBuiltin(CoreInitialization.LAYER0 + "InstanceOf");
144                 ConsistsOf = g.getBuiltin(CoreInitialization.LAYER0 + "ConsistsOf");
145                 PartOf = g.getBuiltin(CoreInitialization.LAYER0 + "PartOf");
146                 HasName = g.getBuiltin(CoreInitialization.LAYER0 + "HasName");
147                 NameOf = g.getBuiltin(CoreInitialization.LAYER0 + "NameOf");
148                 ExternalEntity = g.getBuiltin(CoreInitialization.LAYER0 + "ExternalEntity");
149         }
150
151         public void findBuiltins(ReadGraph g) throws DatabaseException {
152                 RootLibrary = g.getBuiltin("http:/");
153                 String = g.getBuiltin(CoreInitialization.LAYER0 + "String");
154                 Library = g.getBuiltin(CoreInitialization.LAYER0 + "Library");
155                 InstanceOf = g.getBuiltin(CoreInitialization.LAYER0 + "InstanceOf");
156                 ConsistsOf = g.getBuiltin(CoreInitialization.LAYER0 + "ConsistsOf");
157                 PartOf = g.getBuiltin(CoreInitialization.LAYER0 + "PartOf");
158                 HasName = g.getBuiltin(CoreInitialization.LAYER0 + "HasName");
159                 NameOf = g.getBuiltin(CoreInitialization.LAYER0 + "NameOf");
160                 ExternalEntity = g.getBuiltin(CoreInitialization.LAYER0 + "ExternalEntity");
161         }
162
163         void addMissing(int handleIndex, String external) {
164                 allMissingExternals.put(external, handleIndex);
165                 Set<String> removals = new HashSet<>();
166                 for(String ext : missingExternals) if(ext.startsWith(external)) return;
167                 for(String ext : missingExternals) if(external.startsWith(ext)) removals.add(ext);
168                 missingExternals.removeAll(removals);
169                 missingExternals.add(external);
170         }
171
172         void prepare(ReadGraph graph) throws Exception {
173
174                 Resource target = advisor.getTarget();
175                 if(target != null)
176                         indexRoot = graph.syncRequest(new PossibleIndexRoot(target));
177                 
178                 findBuiltins(graph);
179                 readIdentities(graph);
180                 
181 //              System.err.println("ext: " + extensions);
182 //              System.err.println("rc: " + resourceCount);
183 //              System.err.println("ic: " + identities.length);
184                 
185                 ClusterBuilderFactory factory = graph.getService(ClusterBuilderFactory.class);
186                 ClusterBuilder2 builder = factory.create(vg, false);
187                 
188                 this.handles = new int[resourceCount];
189                 TIntObjectMap<Identity> identityMap = TransferableGraphUtils.mapIdentities(identities);
190                 
191                 for(Identity identity : identities) {
192                         IdentityDefinition definition = identity.definition;
193                         if(definition instanceof External) {
194                                 External def = (External)definition;
195                                 if(def.parent == -1) {
196                                     handles[identity.resource] = builder.handle(RootLibrary);
197                                 } else {
198                                         if("@inverse".equals(def.name)) {
199                                                 int parent = handles[def.parent];
200                                                 int child = builder.handle(graph.getInverse(builder.resource(parent)));
201                                                 handles[identity.resource] = child;
202                                         } else {
203                                                 int handle = handles[def.parent];
204                                                 Resource parent = handle != 0 ? builder.resource(handle) : null;
205                                                 // TODO: escape should be removed when names become well-behaving
206                                                 if(parent != null) {
207                                                         resolvedParents.put(graph.getURI(parent), parent);
208                                                     Map<String,Resource> childMap = graph
209                                             .syncRequest(new UnescapedChildMapOfResource(parent),
210                                                     TransientCacheAsyncListener.instance()); 
211                                                         Resource child = childMap.get(def.name); 
212                                                         if(child == null) {
213                                                                 addMissing(identity.resource, graph.getURI(parent) + "/" + def.name);
214                                                         } else {
215                                                                 handles[identity.resource] = builder.handle(child);
216                                                         }
217                                                 } else {
218                                                     addMissing(identity.resource, TransferableGraphUtils.getURI(resourceCount, identityMap, def.parent) + "/" + def.name);
219                                                 }
220                                         }
221                                 }
222                         }
223                         else if(definition instanceof Internal) {
224                                 String uri = TransferableGraphUtils.getTrueURI(resourceCount, identityMap, identity.resource);
225                                 Resource existing = graph.getPossibleResource(uri);
226                                 if(existing != null) {
227                                         existingInternalMap.put(identity.resource, existing);
228                                 }
229                         }
230                         else if(definition instanceof Root) {
231                                 Root root = (Root)definition;
232                                 if(root.name.equals(""))
233                                     handles[identity.resource] = builder.handle(RootLibrary);
234                                 else  {
235                                         Resource existing = advisor.analyzeRoot(graph, root);
236                                         if(existing != null)
237                                             handles[identity.resource] = builder.handle(existing);
238                                 }
239                         }
240                         else if(definition instanceof Optional) {
241                                 External def = (External)definition;
242                                 Resource parent = builder.resource(handles[def.parent]);
243                                 if(parent != null)
244                                         handles[identity.resource] = builder.handle(graph.syncRequest(new UnescapedChildMapOfResource(parent)).get(def.name));                          
245                         }
246                 }               
247                 
248                 //if(!missingExternals.isEmpty()) throw new MissingDependencyException(this);
249                 
250         }
251
252         @Override
253         public Resource createChild(WriteOnlyGraph graph, Resource parent, Resource child, String name) throws DatabaseException {
254             if(child == null) child = graph.newResource();
255                 Resource nameResource = graph.newResource();
256                 graph.claim(nameResource, InstanceOf, null, String);
257                 graph.claimValue(nameResource, name, WriteBindings.STRING);
258                 graph.claim(child, HasName, NameOf, nameResource);
259                 return child;
260         }
261
262         int[] getClustering() {
263                 Variant v = extensions.get(Extensions.CLUSTERING);
264                 if(v == null) return null;
265                 try {
266                         return (int[])v.getValue(Bindings.INT_ARRAY);
267                 } catch (AdaptException e) {
268                         Logger.defaultLogError(e);
269                         return null;
270                 }
271         }
272
273         int[] getClusterSets() {
274                 Variant v = extensions.get(Extensions.CLUSTER_SETS);
275                 if(v == null) return null;
276                 try {
277                         return (int[])v.getValue(Bindings.INT_ARRAY);
278                 } catch (AdaptException e) {
279                         Logger.defaultLogError(e);
280                         return null;
281                 }
282         }
283
284         boolean needTranslation(Datatype type) {
285             return resourceUtil.mayHaveResource(type);
286         }
287
288         void findClusterSet(WriteOnlyGraph graph, Resource rootLibrary, int[] clustering, int[] clusterSets, long[] clusters, int id) throws DatabaseException {
289                 ClusteringSupport support = graph.getService(ClusteringSupport.class);
290                 if(id == Extensions.ROOT_LIBRARY_CLUSTER_SET || id == Extensions.INDEX_ROOT_CLUSTER_SET) return;
291                 Resource indexRootClusterSetResource = rootLibrary;
292                 if(support.isClusterSet(indexRoot)) {
293                         indexRootClusterSetResource = indexRoot;
294                 } else {
295                         graph.setClusterSet4NewResource(rootLibrary);
296                         graph.flushCluster();                   
297                 }
298                 int indexRootCsHandle = builder.handle(indexRootClusterSetResource);
299                 for(int pos=0,index=0;index<clustering.length;index++) {
300                         pos += clustering[index];
301                         if(id < pos) {
302                                 int cs = clusterSets[index]; 
303                                 if(handles[id] == 0) {
304                                         int csHandle = 0;
305                                         if(cs == Extensions.ROOT_LIBRARY_CLUSTER_SET) csHandle = builder.handle(rootLibrary);
306                                         else if(cs == Extensions.INDEX_ROOT_CLUSTER_SET) {
307                                                 if(indexRoot == null) throw new DatabaseException("No index root was available in TG import.");
308                                                 csHandle = indexRootCsHandle;
309                                         }
310                                         else {
311                                                 findClusterSet(graph, rootLibrary, clustering, clusterSets, clusters, cs);
312                                                 csHandle = handles[cs];
313                                         }
314                                         
315                                         if(clusters[index] != 0)
316                                                 builder.selectCluster(clusters[index]);
317                                         else if(cs >= 0)
318                                                 builder.newCluster(csHandle);
319                                         
320                                         handles[id] = builder.newResource(csHandle);
321                                         clusters[index] = support.getCluster(builder.resource(handles[id]));
322                                                         
323                                         builder.createClusterSet(handles[id]);
324                                 }
325                                 return;
326                         }
327                 }
328         }
329
330         void createMissing(final WriteOnlyGraph graph) throws Exception {
331                 
332                 if(allMissingExternals.isEmpty()) return;
333                 
334                 XSupport xs = graph.getService(XSupport.class);
335                 Pair<Boolean,Boolean> serviceMode = xs.getServiceMode();
336                 xs.setServiceMode(true, false);
337                 try {
338                         ArrayList<String> missing = new ArrayList<>(allMissingExternals.keySet());
339                         Collections.sort(missing);
340                         for(String uri : missing) {
341                                 String[] parts = URIStringUtils.splitURI(uri);
342
343                                 Resource parent = resolvedParents.get(parts[0]);
344                                 // TODO: proper exception message
345                                 if(parent == null) {
346                                         throw new IllegalStateException("!!");
347                                 }
348
349                                 Resource childResource = graph.newResource();
350                                 graph.claim(childResource, InstanceOf, null, ExternalEntity);
351
352                                 Resource nameResource = graph.newResource();
353                                 graph.claim(nameResource, InstanceOf, null, String);
354                                 graph.claimValue(nameResource, parts[1], WriteBindings.STRING);
355                                 graph.claim(childResource, HasName, NameOf, nameResource);
356
357                                 graph.claim(parent, ConsistsOf, PartOf, childResource);
358
359                                 resolvedParents.put(uri, childResource);
360
361                                 handles[allMissingExternals.get(uri)] = builder.handle(childResource);
362                         }
363                 } finally {
364                         xs.setServiceMode(serviceMode.first, serviceMode.second);
365                 }
366         }
367
368         void write(final WriteOnlyGraph graph) throws Exception {
369         
370         final SerialisationSupport ss = graph.getService(SerialisationSupport.class);
371         
372         ClusterBuilderFactory factory = graph.getService(ClusterBuilderFactory.class);
373         if(advisor instanceof IImportAdvisor2) {
374             boolean allowImmutable = ((IImportAdvisor2)advisor).allowImmutableModifications();
375             builder = factory.create(vg, allowImmutable);
376         } else {
377             builder = factory.create(vg, false);
378         }
379         
380         createMissing(graph);
381         
382                 final int[] handles = this.handles; 
383                 
384                 int[] clustering = getClustering();
385                 if(clustering != null) {
386                         
387                         int[] clusterSets = getClusterSets();
388                         if(clusterSets != null) {
389
390                                 assert(clustering.length == clusterSets.length);
391
392                                 long[] clusters = new long[clustering.length];
393                                 
394                                 // Create clustering
395                                 for(int i=0;i<clusterSets.length;i++) {
396                                         findClusterSet(graph, graph.getRootLibrary(), clustering, clusterSets, clusters, clusterSets[i]);
397                                 }
398                                 
399                                 // Then create all resources
400                                 int i=0;
401                             for(int j=0;j<clustering.length;j++) {
402                                 int c = clustering[j];
403                                 int s = clusterSets[j];
404                                 int setHandle = 0;
405                                         if(s == Extensions.ROOT_LIBRARY_CLUSTER_SET)
406                                                 setHandle = builder.handle(graph.getRootLibrary());
407                                         else if(s == Extensions.INDEX_ROOT_CLUSTER_SET) {
408                                                 if(indexRoot == null) throw new DatabaseException("No index root was available in TG import.");
409                                                 setHandle = builder.handle(indexRoot);
410                                         }
411                                         else setHandle = handles[s];
412                                         // Preserve clustering only for internal resources
413                                         if(clusters[j] != 0)
414                                                 builder.selectCluster(clusters[j]);
415                                         else if(s >= 0)
416                                                 builder.newCluster(setHandle);
417                                         for(int r=0;r<c;r++, i++)
418                                                 if(handles[i] == 0) handles[i] = builder.newResource();
419                                 }
420
421                                 for(;i<handles.length;++i)
422                                         if(handles[i] == 0) handles[i] = builder.newResource();
423                                 
424                         } else {
425
426                         int i = 0;
427                                 for(int c : clustering) {
428                                         builder.newCluster();
429                                         for(int r=0;r<c;r++, i++)
430                                                 if(handles[i] == 0) handles[i] = builder.newResource();
431                                 }
432
433                                 for(;i<handles.length;++i)
434                                         if(handles[i] == 0) handles[i] = builder.newResource();
435                                 
436                         }
437                         
438                 } else {
439                 
440                         // Create blank resources
441                         for(int i=0;i<handles.length;++i)
442                                 if(handles[i] == 0) handles[i] = builder.newResource();
443
444                 }
445                 
446                 // Internal identities          
447                 for(Identity identity : identities) {
448                         IdentityDefinition definition = identity.definition;
449 //                      if(handles[identity.resource] != 0)
450 //                              continue;
451                         if(definition instanceof External) {
452                                 // Already done everything
453                         }
454                         else if(definition instanceof Internal) {
455                                 Internal def = (Internal)definition;
456                                 
457                                 Resource external = existingInternalMap.get(identity.resource);
458                                 if(external != null) {
459                                         handles[identity.resource] = builder.handle(external);
460                                 } else {
461                                         if(handles[identity.resource] != 0)
462                                                 handles[identity.resource] = builder.handle(advisor.createChild(graph, this, builder.resource(handles[def.parent]), builder.resource(handles[identity.resource]), def.name));
463                                         else
464                                                 handles[identity.resource] = builder.handle(advisor.createChild(graph, this, builder.resource(handles[def.parent]), null, def.name));
465                                 }
466                                 
467                         }
468                         else if(definition instanceof Root) {
469                                 
470                                 Root root = (Root)definition;
471                                 if(handles[identity.resource] != 0)
472                                         handles[identity.resource] = builder.handle(advisor.createRoot(graph, root, builder.resource(handles[identity.resource])));
473                                 else
474                                         handles[identity.resource] = builder.handle(advisor.createRoot(graph, root, null));
475                         }
476                         else if(definition instanceof Optional) {
477                                 Optional def = (Optional)definition;
478                                 if(handles[identity.resource] != 0) {
479                                         Resource child = advisor.createChild(graph, this, builder.resource(handles[def.parent]), builder.resource(handles[identity.resource]), def.name);
480                                         graph.claim(child, InstanceOf, null, Library); // ???
481                                         handles[identity.resource] = builder.handle(child);
482                                 } else {
483                                         Resource child = advisor.createChild(graph, this, builder.resource(handles[def.parent]), null, def.name);
484                                         graph.claim(child, InstanceOf, null, Library); // ???
485                                         handles[identity.resource] = builder.handle(child);
486                                 }
487                         }
488                 }               
489
490                 int[] done = { 0 };
491                 int[] percentage = { 0 };
492
493                 int statementCount = tg.getStatementCount();
494                 tg.forStatements(null, new TransferableGraphSourceProcedure<int[]>() {
495
496                         @Override
497                         public void execute(int[] value) throws Exception {
498                                 
499                                 int sub = value[0];
500                                 int pred = value[1];
501                                 int inv = value[2];
502                                 int obj = value[3];
503
504                                 int subject = handles[sub];
505                                 int predicate = handles[pred];
506                                 int object = handles[obj];
507
508                                 builder.addStatement(graph, subject, predicate, object);        
509                                 if(inv >= 0) {
510                                     int inverse = handles[inv];
511                                     builder.addStatement(graph, object, inverse, subject);    
512                                 }
513
514                                 // Count from 0% -> 50% => total = statementCount*2
515                                 percentage[0] = updatePercentage(percentage[0], done[0]++, statementCount*2);
516                 
517                         }
518                         
519                 }); 
520                 
521                 int valueCount = tg.getValueCount();
522                 done[0] = 0;
523
524                 class ValueProcedure extends InputStream implements TransferableGraphSourceValueProcedure {
525
526             private TGResourceUtil util = new TGResourceUtil();
527                     private DataInput source;
528
529             @Override
530             public void execute(int _resource, Datatype type, DataInput stream) throws Exception {
531
532                 source = stream;
533
534                 //int file = _resource & 0x80000000;
535                 int resource = _resource & 0x7FFFFFFF;
536
537                 Binding binding = Bindings.getBinding(type);
538                 Serializer s = Bindings.getSerializer(binding);
539
540                 builder.beginValue(handles[resource]);
541                 if(util.mayHaveResource(type)) {
542                     Object value = s.deserialize(stream);
543                     util.adaptValue( binding,  value, new LongAdapter() {
544                                 @Override
545                                 public long adapt(long in) {
546                                     try {
547                                         return ss.getRandomAccessId(handles[(int)in]);
548                                     } catch (DatabaseException e) {
549                                         throw new IllegalStateException(e);
550                                     }
551                                 }
552                             });
553                     byte[] bytes = s.serialize(value);
554                     for(byte b : bytes) {
555                         int val = b;
556                         if(val < 0) val += 256;
557                         builder.appendValue(val);
558                     }
559                 } else {
560                     s.skip(this);
561                 }
562                 builder.endValue();
563                 work();
564
565             }
566
567             @Override
568             public int read() throws IOException {
569                 int value = source.readUnsignedByte();
570                 try {
571                     builder.appendValue(value);
572                 } catch (DatabaseException e) {
573                     LOGGER.error("Failed to write value into database", e);
574                 }
575                 return value;
576             }
577
578             @Override
579             public void rawCopy(int resource, int length, DataInput input) throws Exception {
580                 builder.beginValue(handles[resource]);
581                 for (int i = 0; i < length; ++i)
582                     builder.appendValue(input.readUnsignedByte());
583                 builder.endValue();
584                 work();
585             }
586
587             private void work() {
588                 // Count from 50% -> 100% => [valueCount, valueCount*2)
589                 percentage[0] = updatePercentage(percentage[0], valueCount + done[0]++, valueCount*2);
590             }
591                 };
592                 
593                 tg.forValues2(null, new ValueProcedure());
594                 
595                 for(Resource r : existingInternalMap.valueCollection()) {
596                         graph.deny(r, InstanceOf, null, ExternalEntity, null);
597                 }
598                 
599         }
600
601         @Override
602         public long[] getResourceIds(SerialisationSupport serializer) throws DatabaseException {
603                 final int count = handles.length;
604                 long[] resourceIds = new long[count];
605                 for(int i=0;i<count;++i)
606                     resourceIds[i] = serializer.getRandomAccessId(handles[i]);
607                 return resourceIds;
608         }
609 }