svn-gvsig-desktop / trunk / org.gvsig.desktop / org.gvsig.desktop.compat.cdc / org.gvsig.fmap.dal / org.gvsig.fmap.dal.impl / src / main / java / org / gvsig / fmap / dal / feature / paging / impl / FeaturePagingHelperImpl.java @ 40435
History | View | Annotate | Download (16.7 KB)
1 | 40435 | jjdelcerro | /* gvSIG. Geographic Information System of the Valencian Government
|
---|---|---|---|
2 | *
|
||
3 | * Copyright (C) 2007-2008 Infrastructures and Transports Department
|
||
4 | * of the Valencian Government (CIT)
|
||
5 | *
|
||
6 | * This program is free software; you can redistribute it and/or
|
||
7 | * modify it under the terms of the GNU General Public License
|
||
8 | * as published by the Free Software Foundation; either version 2
|
||
9 | * of the License, or (at your option) any later version.
|
||
10 | *
|
||
11 | * This program is distributed in the hope that it will be useful,
|
||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
14 | * GNU General Public License for more details.
|
||
15 | *
|
||
16 | * You should have received a copy of the GNU General Public License
|
||
17 | * along with this program; if not, write to the Free Software
|
||
18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
|
||
19 | * MA 02110-1301, USA.
|
||
20 | *
|
||
21 | */
|
||
22 | |||
23 | /*
|
||
24 | * AUTHORS (In addition to CIT):
|
||
25 | * 2008 {DiSiD Technologies} {Create a JTable TableModel for a FeatureCollection}
|
||
26 | */
|
||
27 | package org.gvsig.fmap.dal.feature.paging.impl; |
||
28 | |||
29 | import org.slf4j.Logger; |
||
30 | import org.slf4j.LoggerFactory; |
||
31 | |||
32 | import org.gvsig.fmap.dal.exception.DataException; |
||
33 | import org.gvsig.fmap.dal.feature.EditableFeature; |
||
34 | import org.gvsig.fmap.dal.feature.Feature; |
||
35 | import org.gvsig.fmap.dal.feature.FeatureQuery; |
||
36 | import org.gvsig.fmap.dal.feature.FeatureSelection; |
||
37 | import org.gvsig.fmap.dal.feature.FeatureSet; |
||
38 | import org.gvsig.fmap.dal.feature.FeatureStore; |
||
39 | import org.gvsig.fmap.dal.feature.FeatureType; |
||
40 | import org.gvsig.fmap.dal.feature.exception.FeatureIndexException; |
||
41 | import org.gvsig.fmap.dal.feature.impl.featureset.DynObjectFeatureFacade; |
||
42 | import org.gvsig.fmap.dal.feature.paging.FeaturePagingHelper; |
||
43 | import org.gvsig.tools.dynobject.DynObject; |
||
44 | import org.gvsig.tools.dynobject.DynObjectSet; |
||
45 | import org.gvsig.tools.dynobject.impl.DefaultDynObjectPagingHelper; |
||
46 | import org.gvsig.tools.exception.BaseException; |
||
47 | import org.gvsig.tools.visitor.VisitCanceledException; |
||
48 | import org.gvsig.tools.visitor.Visitor; |
||
49 | |||
50 | /**
|
||
51 | * Helper class to access the values of a FeatureCollection by position. Handles
|
||
52 | * pagination automatically to avoid filling the memory in case of big
|
||
53 | * collections.
|
||
54 | *
|
||
55 | * TODO: evaluate if its more convenient to read values in the background when
|
||
56 | * the returned value is near the end of the page, instead of loading a page on
|
||
57 | * demand.
|
||
58 | *
|
||
59 | * @author gvSIG Team
|
||
60 | */
|
||
61 | public class FeaturePagingHelperImpl extends DefaultDynObjectPagingHelper |
||
62 | implements FeaturePagingHelper {
|
||
63 | |||
64 | private static final Logger LOG = LoggerFactory |
||
65 | .getLogger(FeaturePagingHelperImpl.class); |
||
66 | |||
67 | private FeatureQuery query;
|
||
68 | |||
69 | private FeatureStore featureStore;
|
||
70 | |||
71 | /** If the selected Features must be returned as the first ones. **/
|
||
72 | private boolean selectionUp = false; |
||
73 | |||
74 | private FeatureSet featSet = null; |
||
75 | private FeatureSelection initialSelection = null; |
||
76 | |||
77 | private Feature[] features = null; |
||
78 | |||
79 | /**
|
||
80 | * Constructs a FeaturePagingHelperImpl from data of a FeatureStore.
|
||
81 | *
|
||
82 | * @param featureStore
|
||
83 | * to extract data from
|
||
84 | * @throws DataException
|
||
85 | * if there is an error initializing the helper
|
||
86 | */
|
||
87 | public FeaturePagingHelperImpl(FeatureStore featureStore)
|
||
88 | throws BaseException {
|
||
89 | this(featureStore, DEFAULT_PAGE_SIZE);
|
||
90 | } |
||
91 | |||
92 | /**
|
||
93 | * Constructs a FeaturePagingHelperImpl from data of a FeatureStore.
|
||
94 | *
|
||
95 | * @param featureStore
|
||
96 | * to extract data from
|
||
97 | * @param pageSize
|
||
98 | * the number of elements per page data
|
||
99 | * @throws DataException
|
||
100 | * if there is an error initializing the helper
|
||
101 | */
|
||
102 | public FeaturePagingHelperImpl(FeatureStore featureStore, int pageSize) |
||
103 | throws BaseException {
|
||
104 | this(featureStore, null, pageSize); |
||
105 | } |
||
106 | |||
107 | /**
|
||
108 | * Constructs a FeaturePagingHelperImpl from data of a FeatureStore.
|
||
109 | *
|
||
110 | * @param featureStore
|
||
111 | * to extract data from
|
||
112 | * @throws DataException
|
||
113 | * if there is an error initializing the helper
|
||
114 | */
|
||
115 | public FeaturePagingHelperImpl(FeatureStore featureStore,
|
||
116 | FeatureQuery featureQuery) throws BaseException {
|
||
117 | this(featureStore, featureQuery, DEFAULT_PAGE_SIZE);
|
||
118 | } |
||
119 | |||
120 | /**
|
||
121 | * Constructs a FeaturePagingHelperImpl from data of a FeatureStore.
|
||
122 | *
|
||
123 | * @param featureSet
|
||
124 | * to extract data from
|
||
125 | * @param pageSize
|
||
126 | * the number of elements per page data
|
||
127 | * @throws DataException
|
||
128 | * if there is an error initializing the helper
|
||
129 | */
|
||
130 | public FeaturePagingHelperImpl(FeatureStore featureStore,
|
||
131 | FeatureQuery featureQuery, int pageSize) throws BaseException { |
||
132 | super();
|
||
133 | FeatureQuery query = featureQuery; |
||
134 | if (featureQuery == null) { |
||
135 | query = featureStore.createFeatureQuery(); |
||
136 | query.setFeatureType(featureStore.getDefaultFeatureType()); |
||
137 | } |
||
138 | |||
139 | this.featureStore = featureStore;
|
||
140 | this.query = query;
|
||
141 | this.query.setPageSize(pageSize);
|
||
142 | |||
143 | if (LOG.isDebugEnabled()) {
|
||
144 | LOG.debug("FeaturePagingHelperImpl created with {} pages, "
|
||
145 | + "and a page size of {}", new Long(getCalculator() |
||
146 | .getNumPages()), new Integer(pageSize)); |
||
147 | } |
||
148 | |||
149 | setDefaultCalculator(new Sizeable() {
|
||
150 | public long getSize() { |
||
151 | FeatureSet featureSet = getFeatureSet(false);
|
||
152 | try {
|
||
153 | return featureSet.getSize();
|
||
154 | } catch (BaseException e) {
|
||
155 | LOG.error("Error getting the size of the FeatureSet: "
|
||
156 | + featureSet, e); |
||
157 | return 0l; |
||
158 | } |
||
159 | } |
||
160 | }, pageSize); |
||
161 | } |
||
162 | |||
163 | /**
|
||
164 | * @return the selectionUp status
|
||
165 | */
|
||
166 | protected boolean isSelectionUp() { |
||
167 | return selectionUp;
|
||
168 | } |
||
169 | |||
170 | public void setSelectionUp(boolean selectionUp) { |
||
171 | this.selectionUp = selectionUp;
|
||
172 | try {
|
||
173 | if (selectionUp) {
|
||
174 | initialSelection = |
||
175 | (FeatureSelection) getFeatureStore().getFeatureSelection() |
||
176 | .clone(); |
||
177 | setCalculator(new OneSubsetOneSetPagingCalculator(
|
||
178 | new FeatureSetSizeableDelegate(initialSelection),
|
||
179 | new FeatureSetSizeableDelegate(getFeatureSet(false)), |
||
180 | getMaxPageSize())); |
||
181 | } else {
|
||
182 | if (initialSelection != null) { |
||
183 | initialSelection.dispose(); |
||
184 | initialSelection = null;
|
||
185 | } |
||
186 | setDefaultCalculator(new FeatureSetSizeableDelegate(
|
||
187 | getFeatureSet(false)), getMaxPageSize());
|
||
188 | } |
||
189 | } catch (BaseException e) {
|
||
190 | LOG.error("Error setting the selection up setting to: "
|
||
191 | + selectionUp, e); |
||
192 | } catch (CloneNotSupportedException e) { |
||
193 | LOG.error("Error cloning the selection "
|
||
194 | + "while setting the selection up", e);
|
||
195 | } |
||
196 | } |
||
197 | |||
198 | public Feature getFeatureAt(long index) throws BaseException { |
||
199 | // Check if we have currently loaded the viewed page data,
|
||
200 | // or we need to load a new one
|
||
201 | long pageForIndex = (long) Math.floor(index / getMaxPageSize()); |
||
202 | |||
203 | if (pageForIndex != getCurrentPage()) {
|
||
204 | setCurrentPage(pageForIndex); |
||
205 | } |
||
206 | |||
207 | long positionForIndex = index - (getCurrentPage() * getMaxPageSize());
|
||
208 | |||
209 | if (positionForIndex >= features.length) {
|
||
210 | throw new FeatureIndexException( |
||
211 | new IndexOutOfBoundsException("positionForIndex too big: " |
||
212 | + positionForIndex)); |
||
213 | } else {
|
||
214 | return features[(int) positionForIndex]; |
||
215 | } |
||
216 | |||
217 | } |
||
218 | |||
219 | public Feature[] getCurrentPageFeatures() { |
||
220 | return features;
|
||
221 | } |
||
222 | |||
223 | /**
|
||
224 | * Gets the feature set.
|
||
225 | * The boolean tells whether we must create the featureset
|
||
226 | * again (for example perhaps we need it after a feature
|
||
227 | * has been added/removed)
|
||
228 | */
|
||
229 | private FeatureSet getFeatureSet(boolean reset) { |
||
230 | |||
231 | if (featSet == null || reset) { |
||
232 | |||
233 | if (featSet != null) { |
||
234 | try {
|
||
235 | featSet.dispose(); |
||
236 | } catch (Exception ex) { |
||
237 | LOG.info("Error while disposing featset.", ex);
|
||
238 | } |
||
239 | } |
||
240 | |||
241 | try {
|
||
242 | FeatureStore featureStore = getFeatureStore(); |
||
243 | synchronized (featureStore) {
|
||
244 | featSet = featureStore.getFeatureSet(getFeatureQuery()); |
||
245 | } |
||
246 | } catch (DataException e) {
|
||
247 | throw new RuntimeException("Error getting a feature set with the query " + getFeatureQuery()); |
||
248 | } |
||
249 | } |
||
250 | return featSet;
|
||
251 | } |
||
252 | |||
253 | public DynObjectSet getDynObjectSet() {
|
||
254 | return getFeatureSet(false).getDynObjectSet(); |
||
255 | } |
||
256 | |||
257 | public void reloadCurrentPage() throws BaseException { |
||
258 | |||
259 | boolean sel_up = this.isSelectionUp(); |
||
260 | |||
261 | setSelectionUp(false);
|
||
262 | if (getCalculator().getCurrentPage() > -1) { |
||
263 | loadCurrentPageData(); |
||
264 | } |
||
265 | |||
266 | if (sel_up) {
|
||
267 | setSelectionUp(true);
|
||
268 | } |
||
269 | } |
||
270 | |||
271 | public void reload() throws BaseException { |
||
272 | |||
273 | /*
|
||
274 | * Force re-creation of feature set
|
||
275 | */
|
||
276 | this.getFeatureSet(true); |
||
277 | |||
278 | |||
279 | setDefaultCalculator(new Sizeable() {
|
||
280 | public long getSize() { |
||
281 | FeatureSet featureSet = getFeatureSet(false);
|
||
282 | try {
|
||
283 | return featureSet.getSize();
|
||
284 | } catch (BaseException e) {
|
||
285 | LOG.error("Error getting the size of the FeatureSet: "
|
||
286 | + featureSet, e); |
||
287 | return 0l; |
||
288 | } |
||
289 | } |
||
290 | }, getCalculator().getMaxPageSize()); |
||
291 | reloadCurrentPage(); |
||
292 | } |
||
293 | |||
294 | public FeatureStore getFeatureStore() {
|
||
295 | return featureStore;
|
||
296 | } |
||
297 | |||
298 | public FeatureQuery getFeatureQuery() {
|
||
299 | return query;
|
||
300 | } |
||
301 | |||
302 | /**
|
||
303 | * Loads all the Features of the current page.
|
||
304 | */
|
||
305 | protected void loadCurrentPageData() throws BaseException { |
||
306 | final int currentPageSize = getCalculator().getCurrentPageSize(); |
||
307 | final Feature[] values = new Feature[currentPageSize]; |
||
308 | |||
309 | long t1 = 0; |
||
310 | if (LOG.isTraceEnabled()) {
|
||
311 | t1 = System.currentTimeMillis();
|
||
312 | } |
||
313 | |||
314 | if (selectionUp) {
|
||
315 | loadCurrentPageDataWithSelectionUp(values); |
||
316 | } else {
|
||
317 | loadCurrentPageDataNoSelection(values); |
||
318 | } |
||
319 | |||
320 | if (LOG.isTraceEnabled()) {
|
||
321 | long t2 = System.currentTimeMillis(); |
||
322 | LOG.trace("Time to load {} features: {} ms", new Integer( |
||
323 | currentPageSize), new Long(t2 - t1)); |
||
324 | } |
||
325 | |||
326 | this.features = values;
|
||
327 | } |
||
328 | |||
329 | private void loadCurrentPageDataWithSelectionUp(final Feature[] values) |
||
330 | throws BaseException {
|
||
331 | FeatureSelection selection = initialSelection; |
||
332 | |||
333 | FeatureSet set = getFeatureSet(false);
|
||
334 | try {
|
||
335 | OneSubsetOneSetPagingCalculator twoSetsCalculator = null;
|
||
336 | if (getCalculator() instanceof OneSubsetOneSetPagingCalculator) { |
||
337 | twoSetsCalculator = |
||
338 | (OneSubsetOneSetPagingCalculator) getCalculator(); |
||
339 | } else {
|
||
340 | twoSetsCalculator = |
||
341 | new OneSubsetOneSetPagingCalculator(
|
||
342 | new FeatureSetSizeableDelegate(selection),
|
||
343 | new FeatureSetSizeableDelegate(set),
|
||
344 | getMaxPageSize(), getCalculator().getCurrentPage()); |
||
345 | setCalculator(twoSetsCalculator); |
||
346 | } |
||
347 | |||
348 | // First load values from the selection, if the current page has
|
||
349 | // elements from it
|
||
350 | if (twoSetsCalculator.hasCurrentPageAnyValuesInFirstSet()) {
|
||
351 | loadDataFromFeatureSet(values, 0, selection,
|
||
352 | twoSetsCalculator.getFirstSetInitialIndex(), |
||
353 | twoSetsCalculator.getFirstSetHowMany(), null);
|
||
354 | } |
||
355 | // Next, load values from the FeatureSet if the current page has values
|
||
356 | // from it
|
||
357 | if (twoSetsCalculator.hasCurrentPageAnyValuesInSecondSet()) {
|
||
358 | loadDataFromFeatureSet( |
||
359 | values, |
||
360 | // The cast will work as that size will be <= maxpagesize,
|
||
361 | // which is an int
|
||
362 | (int) twoSetsCalculator.getFirstSetHowMany(), set,
|
||
363 | twoSetsCalculator.getSecondSetInitialIndex(), |
||
364 | twoSetsCalculator.getSecondSetHowMany(), selection); |
||
365 | } |
||
366 | } finally {
|
||
367 | /*
|
||
368 | * This is the feature set
|
||
369 | * we dont want to lose it
|
||
370 | */
|
||
371 | // set.dispose();
|
||
372 | } |
||
373 | } |
||
374 | |||
375 | private void loadCurrentPageDataNoSelection(final Feature[] values) |
||
376 | throws BaseException {
|
||
377 | |||
378 | long firstPosition = getCalculator().getInitialIndex();
|
||
379 | |||
380 | if (LOG.isDebugEnabled()) {
|
||
381 | LOG.debug("Loading {} Features starting at position {}",
|
||
382 | new Integer(getCalculator().getCurrentPageSize()), new Long( |
||
383 | firstPosition)); |
||
384 | } |
||
385 | |||
386 | FeatureSet featureSet = getFeatureSet(false);
|
||
387 | try {
|
||
388 | loadDataFromFeatureSet(values, 0, featureSet, firstPosition,
|
||
389 | getCalculator().getCurrentPageSize(), null);
|
||
390 | } catch(DataException ex) {
|
||
391 | throw ex;
|
||
392 | // } finally {
|
||
393 | // featureSet.dispose();
|
||
394 | } |
||
395 | |||
396 | } |
||
397 | |||
398 | private void loadDataFromFeatureSet(final Feature[] values, |
||
399 | final int valuesPosition, FeatureSet set, long initialIndex, |
||
400 | final long howMany, final FeatureSelection selectedFeaturesToSkip) |
||
401 | throws DataException {
|
||
402 | |||
403 | try {
|
||
404 | set.accept(new Visitor() {
|
||
405 | |||
406 | private int i = valuesPosition; |
||
407 | |||
408 | public void visit(Object obj) throws VisitCanceledException, |
||
409 | BaseException { |
||
410 | if (i >= valuesPosition + howMany) {
|
||
411 | throw new VisitCanceledException(); |
||
412 | } |
||
413 | Feature current = (Feature) obj; |
||
414 | // Add the current Feature only if we don't skip selected
|
||
415 | // features or the feature is not selected
|
||
416 | if (selectedFeaturesToSkip == null |
||
417 | || !selectedFeaturesToSkip.isSelected(current)) { |
||
418 | values[i] = current.getCopy(); |
||
419 | i++; |
||
420 | } |
||
421 | } |
||
422 | }, initialIndex); |
||
423 | } catch (BaseException e) {
|
||
424 | if (e instanceof DataException) { |
||
425 | throw ((DataException) e);
|
||
426 | } else {
|
||
427 | LOG.error("Error loading the data starting at position {}",
|
||
428 | new Long(initialIndex), e); |
||
429 | } |
||
430 | } |
||
431 | } |
||
432 | |||
433 | public void delete(Feature feature) throws BaseException { |
||
434 | featureStore.delete(feature); |
||
435 | /*
|
||
436 | * Force re-creation of feature set
|
||
437 | */
|
||
438 | this.getFeatureSet(true); |
||
439 | |||
440 | reloadCurrentPage(); |
||
441 | } |
||
442 | |||
443 | public void insert(EditableFeature feature) throws BaseException { |
||
444 | featureStore.insert(feature); |
||
445 | /*
|
||
446 | * Force re-creation of feature set
|
||
447 | */
|
||
448 | this.getFeatureSet(true); |
||
449 | |||
450 | reloadCurrentPage(); |
||
451 | } |
||
452 | |||
453 | public void update(EditableFeature feature) throws BaseException { |
||
454 | featureStore.update(feature); |
||
455 | /*
|
||
456 | * Force re-creation of feature set
|
||
457 | */
|
||
458 | this.getFeatureSet(true); |
||
459 | |||
460 | reloadCurrentPage(); |
||
461 | } |
||
462 | |||
463 | public FeatureType getFeatureType() {
|
||
464 | |||
465 | FeatureType ft = null;
|
||
466 | |||
467 | try {
|
||
468 | ft = featureStore.getDefaultFeatureType(); |
||
469 | } catch (DataException e) {
|
||
470 | LOG.error("Error while getting feature type: " +
|
||
471 | e.getMessage(), e); |
||
472 | } |
||
473 | return ft;
|
||
474 | |||
475 | /*
|
||
476 | *
|
||
477 | FeatureSet featureSet = getFeatureSet();
|
||
478 | try {
|
||
479 | return featureSet.getDefaultFeatureType();
|
||
480 | } finally {
|
||
481 | featureSet.dispose();
|
||
482 | }
|
||
483 | */
|
||
484 | |||
485 | |||
486 | } |
||
487 | |||
488 | protected void doDispose() throws BaseException { |
||
489 | initialSelection.dispose(); |
||
490 | if (featSet != null) { |
||
491 | try {
|
||
492 | featSet.dispose(); |
||
493 | } catch (Exception ex) { |
||
494 | LOG.info("Error while disposing featset.", ex);
|
||
495 | } |
||
496 | } |
||
497 | } |
||
498 | |||
499 | public DynObject[] getCurrentPageDynObjects() { |
||
500 | Feature[] features = getCurrentPageFeatures();
|
||
501 | DynObject[] dynobjects = new DynObject[features.length]; |
||
502 | for (int i = 0; i < dynobjects.length; i++) { |
||
503 | dynobjects[i] = new DynObjectFeatureFacade(features[i]);
|
||
504 | } |
||
505 | return dynobjects;
|
||
506 | } |
||
507 | |||
508 | public DynObject getDynObjectAt(long index) throws BaseException { |
||
509 | return new DynObjectFeatureFacade(getFeatureAt(index)); |
||
510 | } |
||
511 | |||
512 | } |