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 |
/* 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 |
} |