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1
7
8 package javax.sql.rowset.serial;
9
10 import java.sql.*;
11 import java.io.*;
12
13
30 public class SerialClob implements Clob, Serializable, Cloneable  {
31
32
39 private char buf[];
40
41
45 private Clob clob;
46
47
53 private long len;
54
55
61 private long origLen;
62
63
77 public SerialClob(char ch[]) throws SerialException , SQLException {
78
79
83 len = ch.length;
84 buf = new char[(int)len];
85 for (int i = 0; i < len ; i++){
86 buf[i] = ch[i];
87 }
88 origLen = len;
89 }
90
91
117 public SerialClob(Clob clob) throws SerialException , SQLException {
118
119 if (clob == null) {
120 throw new SQLException("Cannot instantiate a SerialClob " +
121 "object with a null Clob object");
122 }
123 len = clob.length();
124 this.clob = clob;
125 buf = new char[(int)len];
126 int read = 0;
127 int offset = 0;
128
129 BufferedReader reader;
130
131 if (clob.getCharacterStream() == null || clob.getAsciiStream() == null) {
132 throw new SQLException("Invalid Clob object. Calls to getCharacterStream " +
133 "or getAsciiStream return null which cannot be serialized.");
134 }
135
136 try {
137 reader = new BufferedReader(clob.getCharacterStream());
138
139 do {
140 read = reader.read(buf, offset, (int)(len - offset));
141 offset += read;
142 } while (read > 0);
143
144 } catch (java.io.IOException ex) {
145 throw new SerialException ("SerialClob: " + ex.getMessage());
146 }
147
148 origLen = len;
149 }
150
151
159 public long length() throws SerialException {
160 return len;
161 }
162
163
173 public java.io.Reader getCharacterStream() throws SerialException {
174 return (java.io.Reader ) new CharArrayReader(buf);
175 }
176
177
193 public java.io.InputStream getAsciiStream() throws SerialException , SQLException {
194 if (this.clob != null) {
195 return this.clob.getAsciiStream();
196 } else {
197 throw new SerialException ("Unsupported operation. SerialClob cannot " +
198 "return a the CLOB value as an ascii stream, unless instantiated " +
199 "with a fully implemented Clob object.");
200 }
201 }
202
203
227 public String getSubString(long pos, int length) throws SerialException {
228
229 if (pos < 1 || pos > this.length()) {
230 throw new SerialException ("Invalid position in BLOB object set");
231 }
232
233 if ((pos-1) + length > this.length()) {
234 throw new SerialException ("Invalid position and substring length");
235 }
236
237 try {
238 return new String (buf, (int)pos - 1, length);
239
240 } catch (StringIndexOutOfBoundsException e) {
241 throw new SerialException ("StringIndexOutOfBoundsException: " +
242 e.getMessage());
243 }
244
245 }
246
247
268 public long position(String searchStr, long start)
269 throws SerialException , SQLException {
270
271 if (start < 1 || start > len) {
272 return -1;
273 }
274
275 char pattern[] = searchStr.toCharArray();
276
277 int pos = (int)start-1;
278 int i = 0;
279 long patlen = pattern.length;
280
281 while (pos < len) {
282 if (pattern[i] == buf[pos]) {
283 if (i + 1 == patlen) {
284 return (pos + 1) - (patlen - 1);
285 }
286 i++; pos++;
288 } else if (pattern[i] != buf[pos]) {
289 pos++; }
291 }
292 return -1; }
294
295
313 public long position(Clob searchStr, long start)
314 throws SerialException , SQLException {
315
316 char cPattern[] = null;
317 try {
318 java.io.Reader r = searchStr.getCharacterStream();
319 cPattern = new char[(int)searchStr.length()];
320 r.read(cPattern);
321 } catch (IOException e) {
322 throw new SerialException ("Error streaming Clob search data");
323 }
324 return position(new String (cPattern), start);
325 }
326
327
345 public int setString(long pos, String str) throws SerialException {
346 return (setString(pos, str, 0, str.length()));
347 }
348
349
370 public int setString(long pos, String str, int offset, int length)
371 throws SerialException {
372 String temp = str.substring(offset);
373 char cPattern[] = temp.toCharArray();
374
375 if (offset < 0 || offset > str.length()) {
376 throw new SerialException ("Invalid offset in byte array set");
377 }
378
379 if (pos < 1 || pos > this.length()) {
380 throw new SerialException ("Invalid position in BLOB object set");
381 }
382
383 if ((long)(length) > origLen) {
384 throw new SerialException ("Buffer is not sufficient to hold the value");
385 }
386
387 if ((length + offset) > str.length()) {
388 throw new SerialException ("Invalid OffSet. Cannot have combined offset " +
390 " and length that is greater that the Blob buffer");
391 }
392
393 int i = 0;
394 pos--; while ( i < length || (offset + i +1) < (str.length() - offset ) ) {
396 this.buf[(int)pos + i ] = cPattern[offset + i ];
397 i++;
398 }
399 return i;
400 }
401
402
420 public java.io.OutputStream setAsciiStream(long pos)
421 throws SerialException , SQLException {
422 if (this.clob.setAsciiStream(pos) != null) {
423 return this.clob.setAsciiStream(pos);
424 } else {
425 throw new SerialException ("Unsupported operation. SerialClob cannot " +
426 "return a writable ascii stream\n unless instantiated with a Clob object " +
427 "that has a setAsciiStream() implementation");
428 }
429 }
430
431
450 public java.io.Writer setCharacterStream(long pos)
451 throws SerialException , SQLException {
452 if (this.clob.setCharacterStream(pos) != null) {
453 return this.clob.setCharacterStream(pos);
454 } else {
455 throw new SerialException ("Unsupported operation. SerialClob cannot " +
456 "return a writable character stream\n unless instantiated with a Clob object " +
457 "that has a setCharacterStream implementation");
458 }
459 }
460
461
474 public void truncate(long length) throws SerialException {
475 if (length > len) {
476 throw new SerialException
477 ("Length more than what can be truncated");
478 } else {
479 len = length;
480
482 if (len == 0) {
483 buf = new char[] {};
484 } else {
485 buf = (this.getSubString(1, (int)len)).toCharArray();
486 }
487
488 }
489 }
490
491
492
493
497 static final long serialVersionUID = -1662519690087375313L;
498 }
499 |
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