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1
25 package com.mysql.jdbc;
26
27 import java.io.ByteArrayInputStream  ;
28 import java.io.OutputStream ;
29
30 import java.sql.SQLException ;
31
32 import java.util.ArrayList ;
33 import java.util.List ;
34
35
54 public class BlobFromLocator implements java.sql.Blob {
55 private String blobColumnName = null;
56
57
58 private ResultSet creatorResultSet;
59
60 private int numColsInResultSet = 0;
61
62 private int numPrimaryKeys = 0;
63
64 private List primaryKeyColumns = null;
65
66 private List primaryKeyValues = null;
67
68 private String quotedId;
69
70 private String tableName = null;
71
72
75 BlobFromLocator(ResultSet creatorResultSetToSet, int blobColumnIndex)
76 throws SQLException {
77 this.creatorResultSet = creatorResultSetToSet;
78
79 this.numColsInResultSet = this.creatorResultSet.fields.length;
80 this.quotedId = this.creatorResultSet.connection.getMetaData()
81 .getIdentifierQuoteString();
82
83 if (this.numColsInResultSet > 1) {
84 this.primaryKeyColumns = new ArrayList ();
85 this.primaryKeyValues = new ArrayList ();
86
87 for (int i = 0; i < this.numColsInResultSet; i++) {
88 if (this.creatorResultSet.fields[i].isPrimaryKey()) {
89 StringBuffer keyName = new StringBuffer ();
90 keyName.append(quotedId);
91
92 String originalColumnName = this.creatorResultSet.fields[i]
93 .getOriginalName();
94
95 if (this.creatorResultSet.connection.getIO()
96 .hasLongColumnInfo()
97 && (originalColumnName != null)
98 && (originalColumnName.length() > 0)) {
99 keyName.append(originalColumnName);
100 } else {
101 keyName.append(this.creatorResultSet.fields[i]
102 .getName());
103 }
104
105 keyName.append(quotedId);
106
107 this.primaryKeyColumns.add(keyName.toString());
108 this.primaryKeyValues.add(this.creatorResultSet
109 .getString(i + 1));
110 }
111 }
112 } else {
113 notEnoughInformationInQuery();
114 }
115
116 this.numPrimaryKeys = this.primaryKeyColumns.size();
117
118 if (this.numPrimaryKeys == 0) {
119 notEnoughInformationInQuery();
120 }
121
122 if (this.creatorResultSet.fields[0].getOriginalTableName() != null) {
123 StringBuffer tableNameBuffer = new StringBuffer ();
124
125 String databaseName = this.creatorResultSet.fields[0]
126 .getDatabaseName();
127
128 if ((databaseName != null) && (databaseName.length() > 0)) {
129 tableNameBuffer.append(quotedId);
130 tableNameBuffer.append(databaseName);
131 tableNameBuffer.append(quotedId);
132 tableNameBuffer.append('.');
133 }
134
135 tableNameBuffer.append(quotedId);
136 tableNameBuffer.append(this.creatorResultSet.fields[0]
137 .getOriginalTableName());
138 tableNameBuffer.append(quotedId);
139
140 this.tableName = tableNameBuffer.toString();
141 } else {
142 StringBuffer tableNameBuffer = new StringBuffer ();
143
144 tableNameBuffer.append(quotedId);
145 tableNameBuffer.append(this.creatorResultSet.fields[0]
146 .getTableName());
147 tableNameBuffer.append(quotedId);
148
149 this.tableName = tableNameBuffer.toString();
150 }
151
152 this.blobColumnName = this.creatorResultSet.getString(blobColumnIndex);
153 }
154
155
163 public java.io.InputStream getBinaryStream() throws SQLException {
164 return new ByteArrayInputStream (getBytes(1L, (int) length()));
165 }
166
167
182 public byte[] getBytes(long pos, int length) throws SQLException {
183 java.sql.ResultSet blobRs = null;
184 java.sql.PreparedStatement pStmt = null;
185
186 StringBuffer query = new StringBuffer ("SELECT SUBSTRING(");
188 query.append(this.blobColumnName);
189 query.append(", ");
190 query.append(pos);
191 query.append(", ");
192 query.append(length);
193 query.append(") FROM ");
194 query.append(this.tableName);
195 query.append(" WHERE ");
196
197 query.append((String ) this.primaryKeyColumns.get(0));
198 query.append(" = ?");
199
200 for (int i = 1; i < this.numPrimaryKeys; i++) {
201 query.append(" AND ");
202 query.append((String ) this.primaryKeyColumns.get(i));
203 query.append(" = ?");
204 }
205
206 try {
207 pStmt = this.creatorResultSet.connection.prepareStatement(query
209 .toString());
210
211 for (int i = 0; i < this.numPrimaryKeys; i++) {
212 pStmt.setString(i + 1, (String ) this.primaryKeyValues.get(i));
213 }
214
215 blobRs = pStmt.executeQuery();
216
217 if (blobRs.next()) {
218 return ((com.mysql.jdbc.ResultSet) blobRs).getBytes(1, true);
219 }
220
221 throw new SQLException (
222 "BLOB data not found! Did primary keys change?",
223 SQLError.SQL_STATE_GENERAL_ERROR);
224 } finally {
225 if (blobRs != null) {
226 try {
227 blobRs.close();
228 } catch (SQLException sqlEx) {
229 ; }
231
232 blobRs = null;
233 }
234
235 if (pStmt != null) {
236 try {
237 pStmt.close();
238 } catch (SQLException sqlEx) {
239 ; }
241
242 pStmt = null;
243 }
244 }
245 }
246
247
256 public long length() throws SQLException {
257 java.sql.ResultSet blobRs = null;
258 java.sql.PreparedStatement pStmt = null;
259
260 StringBuffer query = new StringBuffer ("SELECT LENGTH(");
262 query.append(this.blobColumnName);
263 query.append(") FROM ");
264 query.append(this.tableName);
265 query.append(" WHERE ");
266
267 query.append((String ) this.primaryKeyColumns.get(0));
268 query.append(" = ?");
269
270 for (int i = 1; i < this.numPrimaryKeys; i++) {
271 query.append(" AND ");
272 query.append((String ) this.primaryKeyColumns.get(i));
273 query.append(" = ?");
274 }
275
276 try {
277 pStmt = this.creatorResultSet.connection.prepareStatement(query
279 .toString());
280
281 for (int i = 0; i < this.numPrimaryKeys; i++) {
282 pStmt.setString(i + 1, (String ) this.primaryKeyValues.get(i));
283 }
284
285 blobRs = pStmt.executeQuery();
286
287 if (blobRs.next()) {
288 return blobRs.getLong(1);
289 }
290
291 throw new SQLException (
292 "BLOB data not found! Did primary keys change?",
293 SQLError.SQL_STATE_GENERAL_ERROR);
294 } finally {
295 if (blobRs != null) {
296 try {
297 blobRs.close();
298 } catch (SQLException sqlEx) {
299 ; }
301
302 blobRs = null;
303 }
304
305 if (pStmt != null) {
306 try {
307 pStmt.close();
308 } catch (SQLException sqlEx) {
309 ; }
311
312 pStmt = null;
313 }
314 }
315 }
316
317 private void notEnoughInformationInQuery() throws SQLException {
318 throw new SQLException ("Emulated BLOB locators must come from "
319 + "a ResultSet with only one table selected, and all primary "
320 + "keys selected", SQLError.SQL_STATE_GENERAL_ERROR);
321 }
322
323
326 public long position(byte[] pattern, long start) throws SQLException {
327 java.sql.ResultSet blobRs = null;
328 java.sql.PreparedStatement pStmt = null;
329
330 StringBuffer query = new StringBuffer ("SELECT LOCATE(");
332 query.append("?, ");
333 query.append(this.blobColumnName);
334 query.append(", ");
335 query.append(start);
336 query.append(") FROM ");
337 query.append(this.tableName);
338 query.append(" WHERE ");
339
340 query.append((String ) this.primaryKeyColumns.get(0));
341 query.append(" = ?");
342
343 for (int i = 1; i < this.numPrimaryKeys; i++) {
344 query.append(" AND ");
345 query.append((String ) this.primaryKeyColumns.get(i));
346 query.append(" = ?");
347 }
348
349 try {
350 pStmt = this.creatorResultSet.connection.prepareStatement(query
352 .toString());
353 pStmt.setBytes(1, pattern);
354
355 for (int i = 0; i < this.numPrimaryKeys; i++) {
356 pStmt.setString(i + 2, (String ) this.primaryKeyValues.get(i));
357 }
358
359 blobRs = pStmt.executeQuery();
360
361 if (blobRs.next()) {
362 return blobRs.getLong(1);
363 }
364
365 throw new SQLException (
366 "BLOB data not found! Did primary keys change?",
367 SQLError.SQL_STATE_GENERAL_ERROR);
368 } finally {
369 if (blobRs != null) {
370 try {
371 blobRs.close();
372 } catch (SQLException sqlEx) {
373 ; }
375
376 blobRs = null;
377 }
378
379 if (pStmt != null) {
380 try {
381 pStmt.close();
382 } catch (SQLException sqlEx) {
383 ; }
385
386 pStmt = null;
387 }
388 }
389 }
390
391
405 public long position(java.sql.Blob pattern, long start) throws SQLException {
406 return position(pattern.getBytes(0, (int) pattern.length()), start);
407 }
408
409
412 public OutputStream setBinaryStream(long indexToWriteAt)
413 throws SQLException {
414 throw new NotImplemented();
415 }
416
417
420 public int setBytes(long writeAt, byte[] bytes) throws SQLException {
421 return setBytes(writeAt, bytes, 0, bytes.length);
422 }
423
424
427 public int setBytes(long writeAt, byte[] bytes, int offset, int length)
428 throws SQLException {
429 java.sql.PreparedStatement pStmt = null;
430
431 if ((offset + length) > bytes.length) {
432 length = bytes.length - offset;
433 }
434
435 byte[] bytesToWrite = new byte[length];
436 System.arraycopy(bytes, offset, bytesToWrite, 0, length);
437
438 StringBuffer query = new StringBuffer ("UPDATE ");
440 query.append(this.tableName);
441 query.append(" SET ");
442 query.append(this.blobColumnName);
443 query.append(" = INSERT(");
444 query.append(this.blobColumnName);
445 query.append(", ");
446 query.append(writeAt);
447 query.append(", ");
448 query.append(length);
449 query.append(", ?) WHERE ");
450
451 query.append((String ) this.primaryKeyColumns.get(0));
452 query.append(" = ?");
453
454 for (int i = 1; i < this.numPrimaryKeys; i++) {
455 query.append(" AND ");
456 query.append((String ) this.primaryKeyColumns.get(i));
457 query.append(" = ?");
458 }
459
460 try {
461 pStmt = this.creatorResultSet.connection.prepareStatement(query
463 .toString());
464
465 pStmt.setBytes(1, bytesToWrite);
466
467 for (int i = 0; i < this.numPrimaryKeys; i++) {
468 pStmt.setString(i + 2, (String ) this.primaryKeyValues.get(i));
469 }
470
471 int rowsUpdated = pStmt.executeUpdate();
472
473 if (rowsUpdated != 1) {
474 throw new SQLException (
475 "BLOB data not found! Did primary keys change?",
476 SQLError.SQL_STATE_GENERAL_ERROR);
477 }
478 } finally {
479 if (pStmt != null) {
480 try {
481 pStmt.close();
482 } catch (SQLException sqlEx) {
483 ; }
485
486 pStmt = null;
487 }
488 }
489
490 return (int) length();
491 }
492
493
496 public void truncate(long length) throws SQLException {
497 java.sql.PreparedStatement pStmt = null;
498
499 StringBuffer query = new StringBuffer ("UPDATE ");
501 query.append(this.tableName);
502 query.append(" SET ");
503 query.append(this.blobColumnName);
504 query.append(" = LEFT(");
505 query.append(this.blobColumnName);
506 query.append(", ");
507 query.append(length);
508 query.append(") WHERE ");
509
510 query.append((String ) this.primaryKeyColumns.get(0));
511 query.append(" = ?");
512
513 for (int i = 1; i < this.numPrimaryKeys; i++) {
514 query.append(" AND ");
515 query.append((String ) this.primaryKeyColumns.get(i));
516 query.append(" = ?");
517 }
518
519 try {
520 pStmt = this.creatorResultSet.connection.prepareStatement(query
522 .toString());
523
524 for (int i = 0; i < this.numPrimaryKeys; i++) {
525 pStmt.setString(i + 1, (String ) this.primaryKeyValues.get(i));
526 }
527
528 int rowsUpdated = pStmt.executeUpdate();
529
530 if (rowsUpdated != 1) {
531 throw new SQLException (
532 "BLOB data not found! Did primary keys change?",
533 SQLError.SQL_STATE_GENERAL_ERROR);
534 }
535 } finally {
536 if (pStmt != null) {
537 try {
538 pStmt.close();
539 } catch (SQLException sqlEx) {
540 ; }
542
543 pStmt = null;
544 }
545 }
546 }
547 }
548 |
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