1
2
3 package net.sourceforge.pmd.ast;
4
5 /**
6 * An implementation of interface CharStream, where the stream is assumed to
7 * contain only ASCII characters (with java-like unicode escape processing).
8 */
9
10 public class JavaCharStream implements CharStream
11 {
12 /** Whether parser is static. */
13 public static final boolean staticFlag = false;
14 static final int hexval(char c) throws java.io.IOException {
15 switch(c)
16 {
17 case '0' :
18 return 0;
19 case '1' :
20 return 1;
21 case '2' :
22 return 2;
23 case '3' :
24 return 3;
25 case '4' :
26 return 4;
27 case '5' :
28 return 5;
29 case '6' :
30 return 6;
31 case '7' :
32 return 7;
33 case '8' :
34 return 8;
35 case '9' :
36 return 9;
37
38 case 'a' :
39 case 'A' :
40 return 10;
41 case 'b' :
42 case 'B' :
43 return 11;
44 case 'c' :
45 case 'C' :
46 return 12;
47 case 'd' :
48 case 'D' :
49 return 13;
50 case 'e' :
51 case 'E' :
52 return 14;
53 case 'f' :
54 case 'F' :
55 return 15;
56 }
57
58 throw new java.io.IOException();
59 }
60
61 /** Position in buffer. */
62 public int bufpos = -1;
63 int bufsize;
64 int available;
65 int tokenBegin;
66 protected int bufline[];
67 protected int bufcolumn[];
68
69 protected int column = 0;
70 protected int line = 1;
71
72 protected boolean prevCharIsCR = false;
73 protected boolean prevCharIsLF = false;
74
75 protected java.io.Reader inputStream;
76
77 protected char[] nextCharBuf;
78 protected char[] buffer;
79 protected int maxNextCharInd = 0;
80 protected int nextCharInd = -1;
81 protected int inBuf = 0;
82 protected int tabSize = 8;
83
84 protected void setTabSize(int i) { tabSize = i; }
85 protected int getTabSize(int i) { return tabSize; }
86
87 protected void ExpandBuff(boolean wrapAround)
88 {
89 char[] newbuffer = new char[bufsize + 2048];
90 int newbufline[] = new int[bufsize + 2048];
91 int newbufcolumn[] = new int[bufsize + 2048];
92
93 try
94 {
95 if (wrapAround)
96 {
97 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
98 System.arraycopy(buffer, 0, newbuffer,
99 bufsize - tokenBegin, bufpos);
100 buffer = newbuffer;
101
102 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
103 System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
104 bufline = newbufline;
105
106 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
107 System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
108 bufcolumn = newbufcolumn;
109
110 bufpos += (bufsize - tokenBegin);
111 }
112 else
113 {
114 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
115 buffer = newbuffer;
116
117 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
118 bufline = newbufline;
119
120 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
121 bufcolumn = newbufcolumn;
122
123 bufpos -= tokenBegin;
124 }
125 }
126 catch (Throwable t)
127 {
128 throw new RuntimeException(t.getMessage());
129 }
130
131 available = (bufsize += 2048);
132 tokenBegin = 0;
133 }
134
135 protected void FillBuff() throws java.io.IOException
136 {
137 int i;
138 if (maxNextCharInd == 4096)
139 maxNextCharInd = nextCharInd = 0;
140
141 try {
142 if ((i = inputStream.read(nextCharBuf, maxNextCharInd,
143 4096 - maxNextCharInd)) == -1)
144 {
145 inputStream.close();
146 throw new java.io.IOException();
147 }
148 else
149 maxNextCharInd += i;
150 return;
151 }
152 catch(java.io.IOException e) {
153 if (bufpos != 0)
154 {
155 --bufpos;
156 backup(0);
157 }
158 else
159 {
160 bufline[bufpos] = line;
161 bufcolumn[bufpos] = column;
162 }
163 throw e;
164 }
165 }
166
167 protected char ReadByte() throws java.io.IOException
168 {
169 if (++nextCharInd >= maxNextCharInd)
170 FillBuff();
171
172 return nextCharBuf[nextCharInd];
173 }
174
175 /** @return starting character for token. */
176 public char BeginToken() throws java.io.IOException
177 {
178 if (inBuf > 0)
179 {
180 --inBuf;
181
182 if (++bufpos == bufsize)
183 bufpos = 0;
184
185 tokenBegin = bufpos;
186 return buffer[bufpos];
187 }
188
189 tokenBegin = 0;
190 bufpos = -1;
191
192 return readChar();
193 }
194
195 protected void AdjustBuffSize()
196 {
197 if (available == bufsize)
198 {
199 if (tokenBegin > 2048)
200 {
201 bufpos = 0;
202 available = tokenBegin;
203 }
204 else
205 ExpandBuff(false);
206 }
207 else if (available > tokenBegin)
208 available = bufsize;
209 else if ((tokenBegin - available) < 2048)
210 ExpandBuff(true);
211 else
212 available = tokenBegin;
213 }
214
215 protected void UpdateLineColumn(char c)
216 {
217 column++;
218
219 if (prevCharIsLF)
220 {
221 prevCharIsLF = false;
222 line += (column = 1);
223 }
224 else if (prevCharIsCR)
225 {
226 prevCharIsCR = false;
227 if (c == '\n')
228 {
229 prevCharIsLF = true;
230 }
231 else
232 line += (column = 1);
233 }
234
235 switch (c)
236 {
237 case '\r' :
238 prevCharIsCR = true;
239 break;
240 case '\n' :
241 prevCharIsLF = true;
242 break;
243 case '\t' :
244 column--;
245 column += (tabSize - (column % tabSize));
246 break;
247 default :
248 break;
249 }
250
251 bufline[bufpos] = line;
252 bufcolumn[bufpos] = column;
253 }
254
255 /** Read a character. */
256 public char readChar() throws java.io.IOException
257 {
258 if (inBuf > 0)
259 {
260 --inBuf;
261
262 if (++bufpos == bufsize)
263 bufpos = 0;
264
265 return buffer[bufpos];
266 }
267
268 char c;
269
270 if (++bufpos == available)
271 AdjustBuffSize();
272
273 if ((buffer[bufpos] = c = ReadByte()) == '\\')
274 {
275 UpdateLineColumn(c);
276
277 int backSlashCnt = 1;
278
279 for (;;)
280 {
281 if (++bufpos == available)
282 AdjustBuffSize();
283
284 try
285 {
286 if ((buffer[bufpos] = c = ReadByte()) != '\\')
287 {
288 UpdateLineColumn(c);
289
290 if ((c == 'u') && ((backSlashCnt & 1) == 1))
291 {
292 if (--bufpos < 0)
293 bufpos = bufsize - 1;
294
295 break;
296 }
297
298 backup(backSlashCnt);
299 return '\\';
300 }
301 }
302 catch(java.io.IOException e)
303 {
304 if (backSlashCnt > 1)
305 backup(backSlashCnt-1);
306
307 return '\\';
308 }
309
310 UpdateLineColumn(c);
311 backSlashCnt++;
312 }
313
314
315 try
316 {
317 while ((c = ReadByte()) == 'u')
318 ++column;
319
320 buffer[bufpos] = c = (char)(hexval(c) << 12 |
321 hexval(ReadByte()) << 8 |
322 hexval(ReadByte()) << 4 |
323 hexval(ReadByte()));
324
325 column += 4;
326 }
327 catch(java.io.IOException e)
328 {
329 throw new RuntimeException("Invalid escape character at line " + line +
330 " column " + column + ".");
331 }
332
333 if (backSlashCnt == 1)
334 return c;
335 else
336 {
337 backup(backSlashCnt - 1);
338 return '\\';
339 }
340 }
341 else
342 {
343 UpdateLineColumn(c);
344 return c;
345 }
346 }
347
348 @Deprecated
349 /**
350 * @deprecated
351 * @see #getEndColumn
352 */
353 public int getColumn() {
354 return bufcolumn[bufpos];
355 }
356
357 @Deprecated
358 /**
359 * @deprecated
360 * @see #getEndLine
361 */
362 public int getLine() {
363 return bufline[bufpos];
364 }
365
366 /** Get end column. */
367 public int getEndColumn() {
368 return bufcolumn[bufpos];
369 }
370
371 /** Get end line. */
372 public int getEndLine() {
373 return bufline[bufpos];
374 }
375
376 /** @return column of token start */
377 public int getBeginColumn() {
378 return bufcolumn[tokenBegin];
379 }
380
381 /** @return line number of token start */
382 public int getBeginLine() {
383 return bufline[tokenBegin];
384 }
385
386 /** Retreat. */
387 public void backup(int amount) {
388
389 inBuf += amount;
390 if ((bufpos -= amount) < 0)
391 bufpos += bufsize;
392 }
393
394 /** Constructor. */
395 public JavaCharStream(java.io.Reader dstream,
396 int startline, int startcolumn, int buffersize)
397 {
398 inputStream = dstream;
399 line = startline;
400 column = startcolumn - 1;
401
402 available = bufsize = buffersize;
403 buffer = new char[buffersize];
404 bufline = new int[buffersize];
405 bufcolumn = new int[buffersize];
406 nextCharBuf = new char[4096];
407 }
408
409 /** Constructor. */
410 public JavaCharStream(java.io.Reader dstream,
411 int startline, int startcolumn)
412 {
413 this(dstream, startline, startcolumn, 4096);
414 }
415
416 /** Constructor. */
417 public JavaCharStream(java.io.Reader dstream)
418 {
419 this(dstream, 1, 1, 4096);
420 }
421 /** Reinitialise. */
422 public void ReInit(java.io.Reader dstream,
423 int startline, int startcolumn, int buffersize)
424 {
425 inputStream = dstream;
426 line = startline;
427 column = startcolumn - 1;
428
429 if (buffer == null || buffersize != buffer.length)
430 {
431 available = bufsize = buffersize;
432 buffer = new char[buffersize];
433 bufline = new int[buffersize];
434 bufcolumn = new int[buffersize];
435 nextCharBuf = new char[4096];
436 }
437 prevCharIsLF = prevCharIsCR = false;
438 tokenBegin = inBuf = maxNextCharInd = 0;
439 nextCharInd = bufpos = -1;
440 }
441
442 /** Reinitialise. */
443 public void ReInit(java.io.Reader dstream,
444 int startline, int startcolumn)
445 {
446 ReInit(dstream, startline, startcolumn, 4096);
447 }
448
449 /** Reinitialise. */
450 public void ReInit(java.io.Reader dstream)
451 {
452 ReInit(dstream, 1, 1, 4096);
453 }
454 /** Constructor. */
455 public JavaCharStream(java.io.InputStream dstream, String encoding, int startline,
456 int startcolumn, int buffersize) throws java.io.UnsupportedEncodingException
457 {
458 this(encoding == null ? new java.io.InputStreamReader(dstream) : new java.io.InputStreamReader(dstream, encoding), startline, startcolumn, buffersize);
459 }
460
461 /** Constructor. */
462 public JavaCharStream(java.io.InputStream dstream, int startline,
463 int startcolumn, int buffersize)
464 {
465 this(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
466 }
467
468 /** Constructor. */
469 public JavaCharStream(java.io.InputStream dstream, String encoding, int startline,
470 int startcolumn) throws java.io.UnsupportedEncodingException
471 {
472 this(dstream, encoding, startline, startcolumn, 4096);
473 }
474
475 /** Constructor. */
476 public JavaCharStream(java.io.InputStream dstream, int startline,
477 int startcolumn)
478 {
479 this(dstream, startline, startcolumn, 4096);
480 }
481
482 /** Constructor. */
483 public JavaCharStream(java.io.InputStream dstream, String encoding) throws java.io.UnsupportedEncodingException
484 {
485 this(dstream, encoding, 1, 1, 4096);
486 }
487
488 /** Constructor. */
489 public JavaCharStream(java.io.InputStream dstream)
490 {
491 this(dstream, 1, 1, 4096);
492 }
493
494 /** Reinitialise. */
495 public void ReInit(java.io.InputStream dstream, String encoding, int startline,
496 int startcolumn, int buffersize) throws java.io.UnsupportedEncodingException
497 {
498 ReInit(encoding == null ? new java.io.InputStreamReader(dstream) : new java.io.InputStreamReader(dstream, encoding), startline, startcolumn, buffersize);
499 }
500
501 /** Reinitialise. */
502 public void ReInit(java.io.InputStream dstream, int startline,
503 int startcolumn, int buffersize)
504 {
505 ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, buffersize);
506 }
507 /** Reinitialise. */
508 public void ReInit(java.io.InputStream dstream, String encoding, int startline,
509 int startcolumn) throws java.io.UnsupportedEncodingException
510 {
511 ReInit(dstream, encoding, startline, startcolumn, 4096);
512 }
513 /** Reinitialise. */
514 public void ReInit(java.io.InputStream dstream, int startline,
515 int startcolumn)
516 {
517 ReInit(dstream, startline, startcolumn, 4096);
518 }
519 /** Reinitialise. */
520 public void ReInit(java.io.InputStream dstream, String encoding) throws java.io.UnsupportedEncodingException
521 {
522 ReInit(dstream, encoding, 1, 1, 4096);
523 }
524
525 /** Reinitialise. */
526 public void ReInit(java.io.InputStream dstream)
527 {
528 ReInit(dstream, 1, 1, 4096);
529 }
530
531 /** @return token image as String */
532 public String GetImage()
533 {
534 if (bufpos >= tokenBegin)
535 return new String(buffer, tokenBegin, bufpos - tokenBegin + 1);
536 else
537 return new String(buffer, tokenBegin, bufsize - tokenBegin) +
538 new String(buffer, 0, bufpos + 1);
539 }
540
541 /** @return suffix */
542 public char[] GetSuffix(int len)
543 {
544 char[] ret = new char[len];
545
546 if ((bufpos + 1) >= len)
547 System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
548 else
549 {
550 System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
551 len - bufpos - 1);
552 System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
553 }
554
555 return ret;
556 }
557
558 /** Set buffers back to null when finished. */
559 public void Done()
560 {
561 nextCharBuf = null;
562 buffer = null;
563 bufline = null;
564 bufcolumn = null;
565 }
566
567 /**
568 * Method to adjust line and column numbers for the start of a token.
569 */
570 public void adjustBeginLineColumn(int newLine, int newCol)
571 {
572 int start = tokenBegin;
573 int len;
574
575 if (bufpos >= tokenBegin)
576 {
577 len = bufpos - tokenBegin + inBuf + 1;
578 }
579 else
580 {
581 len = bufsize - tokenBegin + bufpos + 1 + inBuf;
582 }
583
584 int i = 0, j = 0, k = 0;
585 int nextColDiff = 0, columnDiff = 0;
586
587 while (i < len &&
588 bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
589 {
590 bufline[j] = newLine;
591 nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
592 bufcolumn[j] = newCol + columnDiff;
593 columnDiff = nextColDiff;
594 i++;
595 }
596
597 if (i < len)
598 {
599 bufline[j] = newLine++;
600 bufcolumn[j] = newCol + columnDiff;
601
602 while (i++ < len)
603 {
604 if (bufline[j = start % bufsize] != bufline[++start % bufsize])
605 bufline[j] = newLine++;
606 else
607 bufline[j] = newLine;
608 }
609 }
610
611 line = bufline[j];
612 column = bufcolumn[j];
613 }
614
615 }
616