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1
19
20 package org.apache.cayenne.access.trans;
21
22 import java.util.Iterator  ;
23 import java.util.List ;
24
25 import org.apache.cayenne.ObjectId;
26 import org.apache.cayenne.Persistent;
27 import org.apache.cayenne.exp.Expression;
28 import org.apache.cayenne.exp.TraversalHandler;
29 import org.apache.cayenne.map.DbAttribute;
30 import org.apache.cayenne.map.DbRelationship;
31 import org.apache.cayenne.map.EntityInheritanceTree;
32 import org.apache.cayenne.map.ObjEntity;
33 import org.apache.cayenne.query.QualifiedQuery;
34 import org.apache.cayenne.query.Query;
35 import org.apache.cayenne.query.SelectQuery;
36 import org.apache.commons.collections.IteratorUtils;
37
38
43 public class QualifierTranslator
44 extends QueryAssemblerHelper
45 implements TraversalHandler {
46
47 protected StringBuffer qualBuf = new StringBuffer ();
48
49 protected boolean translateParentQual;
50 protected DataObjectMatchTranslator objectMatchTranslator;
51 protected boolean matchingObject;
52
53 public QualifierTranslator() {
54 this(null);
55 }
56
57 public QualifierTranslator(QueryAssembler queryAssembler) {
58 super(queryAssembler);
59 }
60
61
64 public String doTranslation() {
65 qualBuf.setLength(0);
66
67 Expression rootNode = extractQualifier();
68 if (rootNode == null) {
69 return null;
70 }
71
72 rootNode.traverse(this);
75 return qualBuf.length() > 0 ? qualBuf.toString() : null;
76 }
77
78 protected Expression extractQualifier() {
79 Query q = queryAssembler.getQuery();
80
81 Expression qualifier =
82 (isTranslateParentQual())
83 ? ((SelectQuery) q).getParentQualifier()
84 : ((QualifiedQuery) q).getQualifier();
85
86 ObjEntity entity = getObjEntity();
88
89 if (entity != null) {
90 EntityInheritanceTree tree =
91 queryAssembler.getEntityResolver().lookupInheritanceTree(
92 entity);
93 Expression entityQualifier =
94 (tree != null)
95 ? tree.qualifierForEntityAndSubclasses()
96 : entity.getDeclaredQualifier();
97 if (entityQualifier != null) {
98 qualifier =
99 (qualifier != null)
100 ? qualifier.andExp(entityQualifier)
101 : entityQualifier;
102 }
103 }
104
105 return qualifier;
106 }
107
108
112 protected void detectObjectMatch(Expression exp) {
113
118 matchingObject = false;
119
120 if (exp.getOperandCount() != 2) {
121 return;
123 }
124
125 for (int i = 0; i < 2; i++) {
127 Object op = exp.getOperand(i);
128 if (op instanceof Persistent || op instanceof ObjectId) {
129 matchingObject = true;
130
131 if (objectMatchTranslator == null) {
132 objectMatchTranslator = new DataObjectMatchTranslator();
133 }
134 else {
135 objectMatchTranslator.reset();
136 }
137 break;
138 }
139 }
140 }
141
142 protected void appendObjectMatch() {
143 if (!matchingObject || objectMatchTranslator == null) {
144 throw new IllegalStateException ("An invalid attempt to append object match.");
145 }
146
147 matchingObject = false;
149
150 boolean first = true;
151 DbRelationship relationship = objectMatchTranslator.getRelationship();
152
153 if(!relationship.isToMany() && !relationship.isToPK()) {
154 queryAssembler.dbRelationshipAdded(relationship);
155 }
156
157 Iterator it = objectMatchTranslator.keys();
158 while (it.hasNext()) {
159 if (first) {
160 first = false;
161 }
162 else {
163 qualBuf.append(" AND ");
164 }
165
166 String key = (String ) it.next();
167 DbAttribute attr = objectMatchTranslator.getAttribute(key);
168 Object val = objectMatchTranslator.getValue(key);
169
170 processColumn(qualBuf, attr, relationship);
171 qualBuf.append(objectMatchTranslator.getOperation());
172 appendLiteral(qualBuf, val, attr, objectMatchTranslator.getExpression());
173 }
174
175 objectMatchTranslator.reset();
176 }
177
178
179 public void finishedChild(Expression node, int childIndex, boolean hasMoreChildren) {
180
181 if (!hasMoreChildren) {
182 return;
183 }
184
185 StringBuffer buf = (matchingObject) ? new StringBuffer () : qualBuf;
186
187 switch (node.getType()) {
188 case Expression.AND :
189 buf.append(" AND ");
190 break;
191 case Expression.OR :
192 buf.append(" OR ");
193 break;
194 case Expression.EQUAL_TO :
195 if (childIndex == 0
197 && node.getOperandCount() == 2
198 && node.getOperand(1) == null) {
199 buf.append(" IS ");
200 }
201 else {
202 buf.append(" = ");
203 }
204 break;
205 case Expression.NOT_EQUAL_TO :
206 if (childIndex == 0
208 && node.getOperandCount() == 2
209 && node.getOperand(1) == null) {
210 buf.append(" IS NOT ");
211 }
212 else {
213 buf.append(" <> ");
214 }
215 break;
216 case Expression.LESS_THAN :
217 buf.append(" < ");
218 break;
219 case Expression.GREATER_THAN :
220 buf.append(" > ");
221 break;
222 case Expression.LESS_THAN_EQUAL_TO :
223 buf.append(" <= ");
224 break;
225 case Expression.GREATER_THAN_EQUAL_TO :
226 buf.append(" >= ");
227 break;
228 case Expression.IN :
229 buf.append(" IN ");
230 break;
231 case Expression.NOT_IN :
232 buf.append(" NOT IN ");
233 break;
234 case Expression.LIKE :
235 buf.append(" LIKE ");
236 break;
237 case Expression.NOT_LIKE :
238 buf.append(" NOT LIKE ");
239 break;
240 case Expression.LIKE_IGNORE_CASE :
241 buf.append(") LIKE UPPER(");
242 break;
243 case Expression.NOT_LIKE_IGNORE_CASE :
244 buf.append(") NOT LIKE UPPER(");
245 break;
246 case Expression.ADD :
247 buf.append(" + ");
248 break;
249 case Expression.SUBTRACT :
250 buf.append(" - ");
251 break;
252 case Expression.MULTIPLY :
253 buf.append(" * ");
254 break;
255 case Expression.DIVIDE :
256 buf.append(" / ");
257 break;
258 case Expression.BETWEEN :
259 if (childIndex == 0)
260 buf.append(" BETWEEN ");
261 else if (childIndex == 1)
262 buf.append(" AND ");
263 break;
264 case Expression.NOT_BETWEEN :
265 if (childIndex == 0)
266 buf.append(" NOT BETWEEN ");
267 else if (childIndex == 1)
268 buf.append(" AND ");
269 break;
270 }
271
272 if (matchingObject) {
273 objectMatchTranslator.setOperation(buf.toString());
274 objectMatchTranslator.setExpression(node);
275 }
276 }
277
278 public void startNode(Expression node, Expression parentNode) {
279 int count = node.getOperandCount();
280
281 if (count == 2) {
282 detectObjectMatch(node);
284 }
285
286 if (parenthesisNeeded(node, parentNode)) {
287 qualBuf.append('(');
288 }
289
290 if (count == 0) {
291 if (node.getType() == Expression.TRUE) {
293 qualBuf.append("1 = 1");
294 }
295 if (node.getType() == Expression.FALSE) {
296 qualBuf.append("1 = 0");
297 }
298 }
299
300 if (count == 1) {
301 if (node.getType() == Expression.NEGATIVE)
302 qualBuf.append('-');
303 else if (node.getType() == Expression.NOT)
307 qualBuf.append("NOT ");
308 }
309 else if (
310 node.getType() == Expression.LIKE_IGNORE_CASE
311 || node.getType() == Expression.NOT_LIKE_IGNORE_CASE) {
312 qualBuf.append("UPPER(");
313 }
314 }
315
316
319 public void endNode(Expression node, Expression parentNode) {
320
321 if (node.getOperandCount() == 2 && matchingObject) {
323 appendObjectMatch();
324 }
325
326 if (parenthesisNeeded(node, parentNode)) {
327 qualBuf.append(')');
328 }
329
330 if (node.getType() == Expression.LIKE_IGNORE_CASE
331 || node.getType() == Expression.NOT_LIKE_IGNORE_CASE) {
332 qualBuf.append(')');
333 }
334 }
335
336 public void objectNode(Object leaf, Expression parentNode) {
337 if (parentNode.getType() == Expression.OBJ_PATH) {
338 appendObjPath(qualBuf, parentNode);
339 }
340 else if (parentNode.getType() == Expression.DB_PATH) {
341 appendDbPath(qualBuf, parentNode);
342 }
343 else if (parentNode.getType() == Expression.LIST) {
344 appendList(parentNode, paramsDbType(parentNode));
345 }
346 else {
347 appendLiteral(qualBuf, leaf, paramsDbType(parentNode), parentNode);
348 }
349 }
350
351 protected boolean parenthesisNeeded(Expression node, Expression parentNode) {
352 if (parentNode == null)
353 return false;
354
355 if (node.getOperandCount() > 1)
357 return true;
358
359 if (node.getType() == Expression.OBJ_PATH)
360 return false;
361
362 if (node.getType() == Expression.DB_PATH)
363 return false;
364
365 return true;
366 }
367
368 private final void appendList(Expression listExpr, DbAttribute paramDesc) {
369 Iterator it = null;
370 Object list = listExpr.getOperand(0);
371 if (list instanceof List ) {
372 it = ((List ) list).iterator();
373 }
374 else if (list instanceof Object []) {
375 it = IteratorUtils.arrayIterator((Object []) list);
376 }
377 else {
378 String className = (list != null) ? list.getClass().getName() : "<null>";
379 throw new IllegalArgumentException (
380 "Unsupported type for the list expressions: " + className);
381 }
382
383 if (it.hasNext())
386 appendLiteral(qualBuf, it.next(), paramDesc, listExpr);
387 else
388 return;
389
390 while (it.hasNext()) {
391 qualBuf.append(", ");
392 appendLiteral(qualBuf, it.next(), paramDesc, listExpr);
393 }
394 }
395
396
402 public boolean isTranslateParentQual() {
403 return translateParentQual;
404 }
405
406
412 public void setTranslateParentQual(boolean translateParentQual) {
413 this.translateParentQual = translateParentQual;
414 }
415
416 public ObjEntity getObjEntity() {
417 if (isTranslateParentQual()) {
418 SelectQuery query = (SelectQuery) queryAssembler.getQuery();
419 return queryAssembler.getEntityResolver().getObjEntity(
420 query.getParentObjEntityName());
421 }
422 else {
423 return super.getObjEntity();
424 }
425 }
426
427 protected void appendLiteral(
428 StringBuffer buf,
429 Object val,
430 DbAttribute attr,
431 Expression parentExpression) {
432
433 if (!matchingObject) {
434 super.appendLiteral(buf, val, attr, parentExpression);
435 }
436 else if (val == null || (val instanceof Persistent)) {
437 objectMatchTranslator.setDataObject((Persistent) val);
438 }
439 else if(val instanceof ObjectId) {
440 objectMatchTranslator.setObjectId((ObjectId) val);
441 }
442 else {
443 throw new IllegalArgumentException ("Attempt to use literal other than DataObject during object match.");
444 }
445 }
446
447 protected void processRelTermination(StringBuffer buf, DbRelationship rel) {
448
449 if (!matchingObject) {
450 super.processRelTermination(buf, rel);
451 }
452 else {
453 if (rel.isToMany()) {
454 queryAssembler.dbRelationshipAdded(rel);
456 }
457 objectMatchTranslator.setRelationship(rel);
458 }
459 }
460 }
461 |
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