Source Code Cross Referenced for Query.java in  » EJB-Server-resin-3.1.5 » resin » com » caucho » db » sql » Java Source Code / Java DocumentationJava Source Code and Java Documentation

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Java Source Code / Java Documentation » EJB Server resin 3.1.5 » resin » com.caucho.db.sql 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
003:         *
004:         * This file is part of Resin(R) Open Source
005:         *
006:         * Each copy or derived work must preserve the copyright notice and this
007:         * notice unmodified.
008:         *
009:         * Resin Open Source is free software; you can redistribute it and/or modify
010:         * it under the terms of the GNU General Public License as published by
011:         * the Free Software Foundation; either version 2 of the License, or
012:         * (at your option) any later version.
013:         *
014:         * Resin Open Source is distributed in the hope that it will be useful,
015:         * but WITHOUT ANY WARRANTY; without even the implied warranty of
016:         * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
017:         * of NON-INFRINGEMENT.  See the GNU General Public License for more
018:         * details.
019:         *
020:         * You should have received a copy of the GNU General Public License
021:         * along with Resin Open Source; if not, write to the
022:         *
023:         *   Free Software Foundation, Inc.
024:         *   59 Temple Place, Suite 330
025:         *   Boston, MA 02111-1307  USA
026:         *
027:         * @author Scott Ferguson
028:         */
029:
030:        package com.caucho.db.sql;
031:
032:        import com.caucho.db.Database;
033:        import com.caucho.db.store.Transaction;
034:        import com.caucho.db.table.Column;
035:        import com.caucho.db.table.Table;
036:        import com.caucho.db.table.TableIterator;
037:        import com.caucho.log.Log;
038:        import com.caucho.sql.SQLExceptionWrapper;
039:        import com.caucho.util.CharBuffer;
040:        import com.caucho.util.L10N;
041:
042:        import java.io.IOException;
043:        import java.io.InputStream;
044:        import java.sql.SQLException;
045:        import java.util.ArrayList;
046:        import java.util.logging.Level;
047:        import java.util.logging.Logger;
048:
049:        abstract public class Query {
050:            private static final Logger log = Log.open(Query.class);
051:            private static final L10N L = new L10N(Query.class);
052:
053:            private Database _db;
054:
055:            private String _sql;
056:
057:            private FromItem[] _fromItems;
058:            private ParamExpr[] _params;
059:
060:            private boolean _isGroup;
061:            private int _dataFieldCount;
062:
063:            private Query _parent;
064:            private SubSelectExpr _parentSubSelect;
065:
066:            private Expr[] _whereExprs;
067:            protected Expr _whereExpr;
068:
069:            private RowIterateExpr[] _indexExprs;
070:
071:            private ArrayList<SubSelectParamExpr> _paramExprs = new ArrayList<SubSelectParamExpr>();
072:
073:            protected Query(Database db, String sql) {
074:                _db = db;
075:                _sql = sql;
076:            }
077:
078:            protected Query(Database db, String sql, FromItem[] fromItems) {
079:                _db = db;
080:                _sql = sql;
081:                _fromItems = fromItems;
082:            }
083:
084:            /**
085:             * Returns the owning database.
086:             */
087:            public Database getDatabase() {
088:                return _db;
089:            }
090:
091:            /**
092:             * Sets the parent query
093:             */
094:            public void setParent(Query query) {
095:                _parent = query;
096:            }
097:
098:            /**
099:             * Gets the parent query
100:             */
101:            public Query getParent() {
102:                return _parent;
103:            }
104:
105:            /**
106:             * Sets the parent sub-select.
107:             */
108:            public void setSubSelect(SubSelectExpr subSelect) {
109:                _parentSubSelect = subSelect;
110:            }
111:
112:            /**
113:             * Gets the parent sub-select.
114:             */
115:            public SubSelectExpr getSubSelect() {
116:                return _parentSubSelect;
117:            }
118:
119:            /**
120:             * Returns the number of temporary data fields.
121:             */
122:            public int getDataFields() {
123:                return _dataFieldCount;
124:            }
125:
126:            /**
127:             * Sets the number of temporary data fields.
128:             */
129:            public void setDataFields(int fieldCount) {
130:                _dataFieldCount = fieldCount;
131:            }
132:
133:            /**
134:             * Sets the maximum entires
135:             */
136:            public void setLimit(int limit) {
137:            }
138:
139:            /**
140:             * Returns any from items.
141:             */
142:            public FromItem[] getFromItems() {
143:                return _fromItems;
144:            }
145:
146:            /**
147:             * Sets from items.
148:             */
149:            protected void setFromItems(FromItem[] fromItems) {
150:                _fromItems = fromItems;
151:            }
152:
153:            /**
154:             * Sets from items.
155:             */
156:            protected void setFromItems(ArrayList<FromItem> fromItems) {
157:                _fromItems = new FromItem[fromItems.size()];
158:                fromItems.toArray(_fromItems);
159:            }
160:
161:            /**
162:             * Sets the where expr.
163:             */
164:            public void setWhereExpr(Expr expr) {
165:                _whereExpr = expr;
166:            }
167:
168:            /**
169:             * Returns the where exprs
170:             */
171:            public Expr[] getWhereExprs() {
172:                return _whereExprs;
173:            }
174:
175:            /**
176:             * Sets the where exprs.
177:             */
178:            protected void setWhereExprs(Expr[] whereExprs) {
179:                _whereExprs = whereExprs;
180:            }
181:
182:            /**
183:             * Sets the params.
184:             */
185:            public void setParams(ParamExpr[] params) {
186:                _params = params;
187:            }
188:
189:            /**
190:             * Returns the param exprs.
191:             */
192:            public ArrayList<SubSelectParamExpr> getParamExprs() {
193:                return _paramExprs;
194:            }
195:
196:            /**
197:             * Returns the SQL.
198:             */
199:            String getSQL() {
200:                return _sql;
201:            }
202:
203:            /**
204:             * Returns true for select queries.
205:             */
206:            public boolean isSelect() {
207:                return false;
208:            }
209:
210:            public boolean isReadOnly() {
211:                return true;
212:            }
213:
214:            /**
215:             * Sets the current number of group fields.
216:             */
217:            public void setGroup(boolean isGroup) {
218:                _isGroup = isGroup;
219:            }
220:
221:            /**
222:             * Sets true for group operations
223:             */
224:            public boolean isGroup() {
225:                return _isGroup;
226:            }
227:
228:            /**
229:             * Binds the query.
230:             */
231:            protected void bind() throws SQLException {
232:                if (_whereExpr != null) {
233:                    generateWhere(_whereExpr);
234:
235:                    for (int i = 0; i < _whereExprs.length; i++) {
236:                        Expr expr = _whereExprs[i];
237:
238:                        if (expr != null)
239:                            _whereExprs[i] = expr.bind(this );
240:                    }
241:                } else if (_fromItems != null) {
242:                    _whereExprs = new Expr[_fromItems.length + 1];
243:                    _indexExprs = new RowIterateExpr[_fromItems.length];
244:                } else {
245:                    _whereExprs = new Expr[2];
246:                    _indexExprs = new RowIterateExpr[1];
247:                }
248:
249:                for (int i = 0; i < _indexExprs.length; i++) {
250:                    Expr expr = _indexExprs[i];
251:
252:                    if (expr == null)
253:                        _indexExprs[i] = new RowIterateExpr();
254:                    else
255:                        _indexExprs[i] = (RowIterateExpr) _indexExprs[i]
256:                                .bind(this );
257:                }
258:
259:                for (int i = 0; i < _paramExprs.size(); i++) {
260:                    SubSelectParamExpr expr = _paramExprs.get(i);
261:
262:                    expr = (SubSelectParamExpr) expr.bind(_parent);
263:                    _paramExprs.set(i, expr);
264:                }
265:            }
266:
267:            /**
268:             * Optimize the where and order the from items.
269:             */
270:            protected void generateWhere(Expr whereExpr) throws SQLException {
271:                ArrayList<Expr> andProduct = new ArrayList<Expr>();
272:
273:                whereExpr.splitAnd(andProduct);
274:
275:                FromItem[] fromItems = getFromItems();
276:
277:                Expr[] whereExprs = new Expr[fromItems.length + 1];
278:                RowIterateExpr[] indexExprs = new RowIterateExpr[fromItems.length];
279:
280:                _whereExprs = whereExprs;
281:                _indexExprs = indexExprs;
282:
283:                ArrayList<FromItem> costItems = new ArrayList<FromItem>();
284:                orderFromItems(costItems, andProduct);
285:
286:                costItems.clear();
287:                for (int i = fromItems.length; i >= 0; i--) {
288:                    if (i < fromItems.length)
289:                        costItems.add(fromItems[i]);
290:
291:                    AndExpr subWhereExpr = null;
292:                    boolean hasExpr = false;
293:
294:                    int bestIndex = -1;
295:                    long bestCost;
296:
297:                    do {
298:                        bestCost = Long.MAX_VALUE;
299:
300:                        for (int j = andProduct.size() - 1; j >= 0; j--) {
301:                            Expr subExpr = andProduct.get(j);
302:
303:                            long cost = subExpr.cost(costItems);
304:
305:                            if (Integer.MAX_VALUE <= cost && i != 0) {
306:                            } else if (cost < bestCost) {
307:                                bestCost = cost;
308:                                bestIndex = j;
309:                            }
310:                        }
311:
312:                        if (bestCost < Long.MAX_VALUE) {
313:                            Expr expr = andProduct.remove(bestIndex);
314:                            RowIterateExpr indexExpr = null;
315:
316:                            if (i < fromItems.length)
317:                                indexExpr = expr.getIndexExpr(fromItems[i]);
318:
319:                            if (indexExpr != null && indexExprs[i] == null) {
320:                                indexExprs[i] = indexExpr;
321:                            } else {
322:                                // XXX: check if really need to add
323:                                if (subWhereExpr == null)
324:                                    subWhereExpr = new AndExpr();
325:
326:                                subWhereExpr.add(expr);
327:                            }
328:                        }
329:                    } while (bestCost < Long.MAX_VALUE);
330:
331:                    if (subWhereExpr != null)
332:                        whereExprs[i] = subWhereExpr.getSingleExpr();
333:                }
334:
335:                for (int i = 0; i < whereExprs.length; i++) {
336:                    Expr expr = whereExprs[i];
337:                    /*
338:                    if (expr != null)
339:                    expr = expr.bind(this);
340:                     */
341:
342:                    whereExprs[i] = expr;
343:                }
344:
345:                _whereExprs = whereExprs;
346:
347:                if (log.isLoggable(Level.FINE)) {
348:                    log.fine("where-" + (whereExprs.length - 1) + ": static "
349:                            + whereExprs[whereExprs.length - 1]);
350:
351:                    for (int i = whereExprs.length - 2; i >= 0; i--) {
352:                        if (_indexExprs[i] != null)
353:                            log.fine("index-" + i + ": " + _fromItems[i] + " "
354:                                    + _indexExprs[i]);
355:
356:                        log.fine("where-" + i + ": " + _fromItems[i] + " "
357:                                + whereExprs[i]);
358:                    }
359:                }
360:            }
361:
362:            private void orderFromItems(ArrayList<FromItem> costItems,
363:                    ArrayList<Expr> topAndProduct) {
364:                FromItem[] fromItems = getFromItems();
365:
366:                ArrayList<Expr> andProduct = new ArrayList<Expr>(topAndProduct);
367:
368:                for (int i = fromItems.length - 1; i >= 0; i--) {
369:                    costItems.clear();
370:
371:                    for (int j = i + 1; j < fromItems.length; j++)
372:                        costItems.add(fromItems[j]);
373:
374:                    int bestIndex = i;
375:                    long bestCost = Expr.COST_INVALID;
376:
377:                    loop: for (int j = 0; j <= i; j++) {
378:                        FromItem item = fromItems[j];
379:
380:                        costItems.add(item);
381:
382:                        for (int k = 0; k < fromItems.length; k++) {
383:                            if (!fromItems[k].isValid(costItems)) {
384:                                costItems.remove(costItems.size() - 1);
385:                                continue loop;
386:                            }
387:                        }
388:
389:                        long cost = Long.MAX_VALUE;
390:                        for (int k = 0; k < andProduct.size(); k++) {
391:                            Expr expr = andProduct.get(k);
392:
393:                            long subCost = expr.cost(costItems);
394:
395:                            if (Expr.COST_INVALID <= subCost) {
396:                                costItems.remove(costItems.size() - 1);
397:                                continue loop;
398:                            }
399:
400:                            if (subCost < cost)
401:                                cost = subCost;
402:                        }
403:
404:                        costItems.remove(costItems.size() - 1);
405:
406:                        if (cost < bestCost) {
407:                            bestCost = cost;
408:                            bestIndex = j;
409:                        }
410:                    }
411:
412:                    FromItem tempItem = fromItems[i];
413:                    fromItems[i] = fromItems[bestIndex];
414:                    fromItems[bestIndex] = tempItem;
415:
416:                    costItems.add(fromItems[i]);
417:                    for (int k = andProduct.size() - 1; k >= 0; k--) {
418:                        Expr expr = andProduct.get(k);
419:
420:                        long subCost = expr.cost(costItems);
421:
422:                        if (subCost < Expr.COST_NO_TABLE) {
423:                            andProduct.remove(k);
424:                        }
425:                    }
426:                }
427:            }
428:
429:            private String logWhere() {
430:                CharBuffer cb = CharBuffer.allocate();
431:
432:                cb.append("[");
433:                for (int i = 0; i < _whereExprs.length; i++) {
434:                    if (i != 0)
435:                        cb.append(", ");
436:
437:                    if (_whereExprs[i] != null)
438:                        cb.append(_whereExprs[i]);
439:                }
440:
441:                cb.append("]");
442:
443:                return cb.close();
444:            }
445:
446:            /**
447:             * Returns a bound expression for the specified table.column.
448:             */
449:            protected Expr bind(String tableName, String columnName)
450:                    throws SQLException {
451:                FromItem[] fromItems = getFromItems();
452:
453:                if (tableName == null) {
454:                    if ("resin_oid".equals(columnName))
455:                        return new OidExpr(fromItems[0].getTable(), 0);
456:
457:                    for (int i = 0; i < fromItems.length; i++) {
458:                        Table table = fromItems[i].getTable();
459:
460:                        int columnIndex = table.getColumnIndex(columnName);
461:
462:                        if (columnIndex >= 0) {
463:                            Column column = table.getColumn(columnName);
464:
465:                            return new IdExpr(fromItems[i], column);
466:                        }
467:                    }
468:
469:                    Expr expr = bindParent(tableName, columnName);
470:                    if (expr != null) {
471:                        return expr;
472:                    }
473:
474:                    throw new SQLException(L.l("`{0}' is an unknown column.",
475:                            columnName));
476:                } else {
477:                    for (int i = 0; i < fromItems.length; i++) {
478:                        if (tableName.equals(fromItems[i].getName())) {
479:                            Table table = fromItems[i].getTable();
480:
481:                            if ("resin_oid".equals(columnName))
482:                                return new OidExpr(table, i);
483:
484:                            int columnIndex = table.getColumnIndex(columnName);
485:
486:                            if (columnIndex < 0) {
487:                                Expr expr = bindParent(tableName, columnName);
488:                                if (expr != null)
489:                                    return expr;
490:
491:                                throw new SQLException(
492:                                        L
493:                                                .l(
494:                                                        "`{0}' is an unknown column in \n  {1}.",
495:                                                        columnName, _sql));
496:                            }
497:
498:                            Column column = table.getColumn(columnName);
499:
500:                            return new IdExpr(fromItems[i], column);
501:                        }
502:                    }
503:
504:                    Expr expr = bindParent(tableName, columnName);
505:                    if (expr != null)
506:                        return expr;
507:
508:                    throw new SQLException(L.l(
509:                            "`{0}' is an unknown table.\n{1}", tableName,
510:                            getSQL()));
511:                }
512:            }
513:
514:            /**
515:             * Binds as a subselect.
516:             */
517:            private Expr bindParent(String tableName, String columnName)
518:                    throws SQLException {
519:                if (_parent != null) {
520:                    Expr expr = _parent.bind(tableName, columnName);
521:
522:                    if (expr != null) {
523:                        SubSelectParamExpr paramExpr;
524:
525:                        paramExpr = new SubSelectParamExpr(this , expr,
526:                                _paramExprs.size());
527:                        _paramExprs.add(paramExpr);
528:
529:                        return paramExpr;
530:                    }
531:                }
532:
533:                return null;
534:            }
535:
536:            /**
537:             * Clears the paramters.
538:             */
539:            public void clearParameters() {
540:                for (int i = 0; i < _params.length; i++)
541:                    _params[i].clear();
542:            }
543:
544:            /**
545:             * Sets the indexed parameter as a boolean.
546:             */
547:            public void setBoolean(int index, boolean value) {
548:                _params[index - 1].setBoolean(value);
549:            }
550:
551:            /**
552:             * Sets the indexed parameter as a string.
553:             */
554:            public void setString(int index, String value) {
555:                _params[index - 1].setString(value);
556:            }
557:
558:            /**
559:             * Sets the indexed parameter as a long.
560:             */
561:            public void setLong(int index, long value) {
562:                _params[index - 1].setLong(value);
563:            }
564:
565:            /**
566:             * Sets the indexed parameter as a double.
567:             */
568:            public void setDouble(int index, double value) {
569:                _params[index - 1].setDouble(value);
570:            }
571:
572:            /**
573:             * Sets the indexed parameter as a date value.
574:             */
575:            public void setDate(int index, long value) {
576:                _params[index - 1].setDate(value);
577:            }
578:
579:            /**
580:             * Sets the indexed parameter as a binary stream
581:             */
582:            public void setBinaryStream(int index, InputStream is, int length) {
583:                _params[index - 1].setBinaryStream(is, length);
584:            }
585:
586:            /**
587:             * Executes the query.
588:             */
589:            abstract public void execute(QueryContext queryCtx, Transaction xa)
590:                    throws SQLException;
591:
592:            /**
593:             * Starts the query.
594:             */
595:            protected boolean start(TableIterator[] rows, int rowLength,
596:                    QueryContext queryContext, Transaction xa)
597:                    throws SQLException {
598:                try {
599:                    Expr[] whereExprs = _whereExprs;
600:
601:                    // Test the constant expression
602:                    if (whereExprs == null || whereExprs[rowLength] == null) {
603:                    } else if (!whereExprs[rowLength].isSelect(queryContext)) {
604:                        return false;
605:                    }
606:
607:                    if (rowLength == 0)
608:                        return true;
609:
610:                    for (int i = rowLength - 1; i >= 0; i--) {
611:                        TableIterator row = rows[i];
612:                        RowIterateExpr iterExpr = _indexExprs[i];
613:
614:                        if (!iterExpr.init(queryContext, row)) {
615:                            return false;
616:                        }
617:
618:                        // XXX: check to make sure others actually lock this properly
619:                        //if (! xa.isAutoCommit())
620:                        //  xa.lockRead(row.getTable().getLock());
621:                    }
622:
623:                    return (initBlockRow(rowLength - 1, rows, queryContext) || nextBlock(
624:                            rowLength - 1, rows, rowLength, queryContext));
625:                } catch (IOException e) {
626:                    throw new SQLExceptionWrapper(e);
627:                }
628:            }
629:
630:            /**
631:             * Returns the next tuple from the query.
632:             */
633:            protected boolean nextTuple(TableIterator[] rows, int rowLength,
634:                    QueryContext queryContext, Transaction xa)
635:                    throws SQLException {
636:                try {
637:                    if (rowLength == 0)
638:                        return false;
639:
640:                    RowIterateExpr[] indexExprs = _indexExprs;
641:                    Expr[] whereExprs = _whereExprs;
642:
643:                    for (int i = 0; i < rowLength; i++) {
644:                        TableIterator table = rows[i];
645:                        RowIterateExpr indexExpr = indexExprs[i];
646:
647:                        Expr whereExpr = whereExprs == null ? null
648:                                : whereExprs[i];
649:
650:                        while (indexExpr.nextRow(queryContext, table)) {
651:                            if (whereExpr == null
652:                                    || whereExpr.isSelect(queryContext)) {
653:                                if (i == 0
654:                                        || initBlockRow(i - 1, rows,
655:                                                queryContext)) {
656:                                    return true;
657:                                }
658:                            }
659:                        }
660:                    }
661:
662:                    return nextBlock(rowLength - 1, rows, rowLength,
663:                            queryContext);
664:                } catch (IOException e) {
665:                    throw new SQLExceptionWrapper(e);
666:                }
667:            }
668:
669:            /**
670:             * Initialize this row and all previous rows within this block group.
671:             */
672:            private boolean nextBlock(int i, TableIterator[] rows,
673:                    int rowLength, QueryContext queryContext)
674:                    throws IOException, SQLException {
675:                TableIterator rowIter = rows[i];
676:                RowIterateExpr iterExpr = _indexExprs[i];
677:
678:                while (true) {
679:                    if (i > 0
680:                            && nextBlock(i - 1, rows, rowLength, queryContext)) {
681:                        return true;
682:                    }
683:
684:                    if (!iterExpr.nextBlock(queryContext, rowIter)) {
685:                        return false;
686:                    }
687:
688:                    if (!iterExpr.allowChildRowShift(queryContext, rows[i]))
689:                        return false;
690:
691:                    for (int j = i - 1; j >= 0; j--) {
692:                        if (!iterExpr.init(queryContext, rows[j]))
693:                            return false;
694:                    }
695:
696:                    if (initBlockRow(rowLength - 1, rows, queryContext))
697:                        return true;
698:                }
699:            }
700:
701:            /**
702:             * Initialize this row and all previous rows within this block group.
703:             */
704:            private boolean initBlockRow(int i, TableIterator[] rows,
705:                    QueryContext queryContext) throws IOException, SQLException {
706:                RowIterateExpr iterExpr = _indexExprs[i];
707:
708:                Expr[] whereExprs = _whereExprs;
709:                Expr expr = whereExprs == null ? null : whereExprs[i];
710:
711:                TableIterator rowIter = rows[i];
712:
713:                if (!iterExpr.initRow(queryContext, rowIter)) {
714:                    return false;
715:                }
716:
717:                while (expr != null && !expr.isSelect(queryContext) || i > 0
718:                        && !initBlockRow(i - 1, rows, queryContext)) {
719:                    if (!iterExpr.nextRow(queryContext, rowIter)) {
720:                        return false;
721:                    }
722:                }
723:
724:                return true;
725:            }
726:
727:            /**
728:             * Frees any blocks for the rows.
729:             */
730:            protected void freeRows(TableIterator[] rows, int rowLength) {
731:                for (rowLength--; rowLength >= 0; rowLength--) {
732:                    if (rows[rowLength] != null)
733:                        rows[rowLength].free();
734:                }
735:            }
736:        }
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