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1
19
20 package za.org.coefficient.util.common;
21
22 import za.org.coefficient.core.Constants;
23 import za.org.coefficient.interfaces.Pager;
24
25 import java.util.ArrayList  ;
26 import java.util.HashMap ;
27 import java.util.Iterator ;
28 import java.util.List ;
29
30
36 public class HibernatePager implements Pager, java.io.Serializable {
37
39 private static final String AND = "and";
40 private static final String OR = "or";
41
42
44 private ArrayList andVals = new ArrayList ();
45 private ArrayList orVals = new ArrayList ();
46 private ArrayList page = new ArrayList ();
47 private Class pagerClass;
48 private String orderByField;
49 private String userQuery;
50 private StringBuffer andConstraints = new StringBuffer ("");
51 private StringBuffer fromClause = new StringBuffer ("");
52 private StringBuffer orConstraints = new StringBuffer ("");
53 private Object [] userValues;
54 private boolean ascending = true;
55 private boolean hasNext = false;
56 private int currentPageNumber = 1;
57 private int pageSize = Constants.MAX_ELEMENTS_PER_PAGE;
58 private int total = 0;
59
60
62 public HibernatePager() {
63 }
64
65 public HibernatePager(String searchQuery, Object [] values) throws Exception {
66 userQuery = searchQuery;
67 userValues = values;
68 this.initialize();
69 }
70
71 public HibernatePager(String searchQuery, Object [] values, int pageSize)
72 throws Exception {
73 userQuery = searchQuery;
74 userValues = values;
75 this.pageSize = pageSize;
76 this.initialize();
77 }
78
79 public HibernatePager(Class pageClass, String orderByField)
80 throws Exception {
81 this.pagerClass = pageClass;
82 this.orderByField = orderByField;
83 this.initialize();
84 }
85
86 public HibernatePager(Class pageClass, String orderByField,
87 boolean orderByAscending) throws Exception {
88 this.pagerClass = pageClass;
89 this.orderByField = orderByField;
90 this.ascending = orderByAscending;
91 this.initialize();
92 }
93
94 public HibernatePager(Class pageClass, String orderByField, int pageSize)
95 throws Exception {
96 this.pagerClass = pageClass;
97 this.orderByField = orderByField;
98 this.pageSize = pageSize;
99 this.initialize();
100 }
101
102 public HibernatePager(Class pageClass, String orderByField, int pageSize,
103 boolean orderByAscending) throws Exception {
104 this.pagerClass = pageClass;
105 this.orderByField = orderByField;
106 this.ascending = orderByAscending;
107 this.pageSize = pageSize;
108 this.initialize();
109 }
110
111 public HibernatePager(Class pageClass, String orderByField,
112 boolean orderByAscending, HashMap andSearchParams) throws Exception {
113 this.pagerClass = pageClass;
114 this.orderByField = orderByField;
115 this.ascending = orderByAscending;
116 this.setAndSearchParams(andSearchParams);
117 }
118
119 public HibernatePager(Class pageClass, String orderByField,
120 boolean orderByAscending, HashMap andSearchParams,
121 HashMap orSearchParams) throws Exception {
122 this.pagerClass = pageClass;
123 this.orderByField = orderByField;
124 this.ascending = orderByAscending;
125 this.setAndSearchParams(andSearchParams);
126 this.setOrSearchParams(orSearchParams);
127 }
128
129 public HibernatePager(Class pageClass, String orderByField, int pageSize,
130 HashMap andSearchParams) throws Exception {
131 this.pagerClass = pageClass;
132 this.orderByField = orderByField;
133 this.pageSize = pageSize;
134 this.setAndSearchParams(andSearchParams);
135 }
136
137 public HibernatePager(Class pageClass, String orderByField, int pageSize,
138 HashMap andSearchParams, HashMap orSearchParams) throws Exception {
139 this.pagerClass = pageClass;
140 this.orderByField = orderByField;
141 this.pageSize = pageSize;
142 this.setAndSearchParams(andSearchParams);
143 this.setOrSearchParams(orSearchParams);
144 }
145
146 public HibernatePager(Class pageClass, String orderByField, int pageSize,
147 HashMap andSearchParams, boolean orderByAscending) throws Exception {
148 this.pagerClass = pageClass;
149 this.orderByField = orderByField;
150 this.ascending = orderByAscending;
151 this.pageSize = pageSize;
152 this.setAndSearchParams(andSearchParams);
153 }
154
155 public HibernatePager(Class pageClass, String orderByField, int pageSize,
156 HashMap andSearchParams, HashMap orSearchParams,
157 boolean orderByAscending) throws Exception {
158 this.pagerClass = pageClass;
159 this.orderByField = orderByField;
160 this.ascending = orderByAscending;
161 this.pageSize = pageSize;
162 this.setAndSearchParams(andSearchParams);
163 this.setOrSearchParams(orSearchParams);
164 }
165
166
168
180 public void setAndSearchParams(HashMap searchParams) throws Exception {
181 setSearchParams(searchParams, AND);
182 }
183
184
188 public int getCurrentPageNumber() {
189 return currentPageNumber;
190 }
191
192
195 public void setFromClauses(HashMap fromElements) throws Exception {
196 fromClause = new StringBuffer ();
197 if (fromElements != null) {
198 for (Iterator it = fromElements.keySet()
199 .iterator(); it.hasNext();) {
200 String key = (String ) it.next();
201 String val = (String ) fromElements.get(key);
202 fromClause.append(" , ");
203 fromClause.append(key);
204 if (val != null) {
205 fromClause.append(" in ");
206 fromClause.append(" objs.");
207 fromClause.append(val);
208 }
209 }
210 }
211 this.initialize();
212 }
213
214 public void setFromWhereAndInitialize(HashMap andSearchParams,
215 HashMap orSearchParams, HashMap fromElements) throws Exception {
216 this.setFromClauses(fromElements);
217 this.setAndSearchParams(andSearchParams);
218 this.setOrSearchParams(orSearchParams);
219 this.initialize();
220 }
221
222
226 public int getMaxPageNumber() {
227 return (int) (Math.ceil(((double) total) / pageSize));
228 }
229
230
242 public void setOrSearchParams(HashMap searchParams) throws Exception {
243 setSearchParams(searchParams, OR);
244 }
245
246 public void setPageSize(int pageSize) {
247 this.pageSize = pageSize;
248 }
249
250 public int getPageSize() {
251 return this.pageSize;
252 }
253
254 public void setQuery(String queryString, Object [] values) {
255 userQuery = queryString;
256 userValues = values;
257 this.initialize();
258 }
259
260
264 public int getTotalNumberOfResults() {
265 return total;
266 }
267
268
272 public List currentPage() {
273 return page;
274 }
275
276
283 public List goToPage(int pageNumber) {
284 if (pageNumber <= (Math.ceil(((double) total) / pageSize))) {
285 this.performQuery(((pageNumber - 1) * pageSize));
286 currentPageNumber = pageNumber;
287 hasNext = (currentPageNumber * pageSize) < total;
288 }
289
290 return currentPage();
291 }
292
293
297 public boolean hasNextPage() {
298 return hasNext;
299 }
300
301
305 public boolean hasPreviousPage() {
306 return currentPageNumber != 1;
307 }
308
309
312 public void initialize() {
313 this.performQuery(0);
314 hasNext = (currentPageNumber * pageSize) < total;
315 }
316
317
320 public void next() {
321 if (hasNext) {
322 this.performQuery((currentPageNumber * pageSize));
323 currentPageNumber++;
324 hasNext = (currentPageNumber * pageSize) < total;
325 }
326 }
327
328
332 public List nextPage() {
333 this.next();
334
335 return this.currentPage();
336 }
337
338
341 public void previous() {
342 if (hasPreviousPage()) {
343 page.clear();
344 performQuery((pageSize * (currentPageNumber - 1)) - pageSize);
345 currentPageNumber--;
346 hasNext = true;
347 }
348 }
349
350
354 public List previousPage() {
355 this.previous();
356
357 return this.currentPage();
358 }
359
360 private void setIntoConstraint(boolean and, String addition) {
361 if (and) {
362 andConstraints.append(addition);
363 } else {
364 orConstraints.append(addition);
365 }
366 }
367
368 private void setIntoVals(boolean and, Object val) {
369 if (and) {
370 andVals.add(val);
371 } else {
372 orVals.add(val);
373 }
374 }
375
376 private int getLengthForConstraint(boolean and) {
377 if (and) {
378 return andConstraints.length();
379 } else {
380 return orConstraints.length();
381 }
382 }
383
384 private void setSearchParams(HashMap searchParams, String logicalOperator)
385 throws Exception {
386 boolean and = AND.equals(logicalOperator);
387 if (and) {
388 andConstraints = new StringBuffer ("");
389 andVals = new ArrayList ();
390 } else {
391 orConstraints = new StringBuffer ("");
392 orVals = new ArrayList ();
393 }
394
395 if (searchParams != null) {
396 for (Iterator it = searchParams.keySet()
397 .iterator(); it.hasNext();) {
398 String field = (String ) it.next();
399 Object value = searchParams.get(field);
400 if (getLengthForConstraint(and) != 0) {
401 if (and) {
402 andConstraints.append(" and ");
403 } else {
404 orConstraints.append(" or ");
405 }
406 }
407 boolean not = false;
408 String operator = "like";
409 if (field.startsWith("!")) {
410 not = true;
411 field = field.substring(1, field.length());
412 operator = "!=";
413 } else if (field.startsWith("<=")) {
414 operator = "<=";
415 field = field.substring(2, field.length());
416 } else if (field.startsWith(">=")) {
417 operator = ">=";
418 field = field.substring(2, field.length());
419 } else if (field.startsWith("<")) {
420 operator = "<";
421 field = field.substring(1, field.length());
422 } else if (field.startsWith(">")) {
423 operator = ">";
424 field = field.substring(1, field.length());
425 }
426
427 if (value instanceof Boolean ) {
428 if (not) {
429 setIntoConstraint(and, " objs." + field + " != ? ");
430 } else {
431 setIntoConstraint(and, " objs." + field + " = ? ");
432 }
433 setIntoVals(and, value);
434 } else {
435 if (value == null) {
436 if (not) {
437 setIntoConstraint(and,
438 " objs." + field + " is not null ");
439 } else {
440 setIntoConstraint(and,
441 " objs." + field + " is null ");
442 }
443 } else {
444 if(value instanceof String ) {
445 setIntoConstraint(and,
446 " upper(objs." + field + ") " + operator + " ? ");
447 value = ((String )value).toUpperCase();
448 } else {
449 setIntoConstraint(and,
450 " objs." + field + " " + operator + " ? ");
451 }
452 setIntoVals(and, value);
453 }
454 }
455 }
456 }
457 this.initialize();
458 }
459
460 private Object [] convertValsToArray() {
461 int i = 0;
462 Object [] oVals = new Object [andVals.size() + orVals.size()];
463 for (Iterator it = andVals.iterator(); it.hasNext(); i++) {
464 Object val = it.next();
465 oVals[i] = val;
466 }
467 for (Iterator it = orVals.iterator(); it.hasNext(); i++) {
468 Object val = it.next();
469 oVals[i] = val;
470 }
471
472 return oVals;
473 }
474
475 private void performQuery(int startElement) {
476 try {
477 Object [] oVals = null;
478 String sql = null;
479 if ((userQuery == null) || (userQuery.length() == 0)) {
480 oVals = convertValsToArray();
481 StringBuffer query = new StringBuffer ("select objs ");
482 query.append(" from ");
483 query.append(pagerClass.getName());
484 query.append(" as objs");
485 if (fromClause.length() != 0) {
486 query.append(fromClause.toString());
487 }
488 if (andConstraints.length() != 0) {
489 query.append(" where ");
490 query.append(andConstraints.toString());
491 }
492 if (orConstraints.length() != 0) {
493 if (andConstraints.length() == 0) {
494 query.append(" where ");
495 } else {
496 query.append(" and ");
497 }
498 query.append(" ( ");
499 query.append(orConstraints.toString());
500 query.append(" ) ");
501 }
502 query.append(" order by objs.");
503 query.append(orderByField);
504 if (!ascending) {
505 query.append(" desc");
506 }
507 sql = query.toString();
508 } else {
509 sql = userQuery.toString();
510 oVals = userValues;
511 }
512
513 total = ((Integer )InvokerFactory.getRemoteInvoker()
514 .invokeMethodOnService("Search", "getPage",
515 new Object []{sql, new Integer (pageSize),
516 new Integer (startElement),
517 oVals, page})).intValue();
518 } catch (Exception e) {
519 System.err.println(
520 "<< could not execute query from pager for class: "
521 + pagerClass.getName() + " with orderByField: " + orderByField);
522 e.printStackTrace();
523 }
524 }
525 }
526 |
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