Commit | Line | Data |
---|---|---|
486efb2e AM |
1 | /*******************************************************************************. |
2 | * Copyright (c) 2011-2012 Ericsson, Ecole Polytechnique de Montreal and others | |
3 | * | |
4 | * All rights reserved. This program and the accompanying materials are made | |
5 | * available under the terms of the Eclipse Public License v1.0 which | |
6 | * accompanies this distribution, and is available at | |
7 | * http://www.eclipse.org/legal/epl-v10.html | |
8 | * | |
9 | * Contributors: Matthew Khouzam - Initial Design and implementation | |
10 | * Contributors: Francis Giraldeau - Initial API and implementation | |
11 | * Contributors: Philippe Proulx - Some refinement and optimization | |
74e4b6b9 | 12 | * Contributors: Etienne Bergeron <Etienne.Bergeron@gmail.com> - fix zero size read + cleanup |
486efb2e AM |
13 | *******************************************************************************/ |
14 | ||
15 | package org.eclipse.linuxtools.ctf.core.event.io; | |
16 | ||
486efb2e AM |
17 | import java.nio.ByteBuffer; |
18 | import java.nio.ByteOrder; | |
19 | ||
db8e8f7d AM |
20 | import org.eclipse.linuxtools.ctf.core.trace.CTFReaderException; |
21 | ||
486efb2e AM |
22 | /** |
23 | * <b><u>BitBuffer</u></b> | |
24 | * <p> | |
25 | * A bitwise buffer capable of accessing fields with bit offsets. | |
26 | * @since 2.0 | |
27 | */ | |
0594c61c | 28 | public final class BitBuffer { |
486efb2e AM |
29 | |
30 | // ------------------------------------------------------------------------ | |
31 | // Constants | |
32 | // ------------------------------------------------------------------------ | |
33 | ||
34 | /* default bit width */ | |
35 | /** 8 bits to a char */ | |
36 | public static final int BIT_CHAR = 8; | |
37 | /** 16 bits to a short */ | |
38 | public static final int BIT_SHORT = 16; | |
39 | /** 32 bits to an int */ | |
40 | public static final int BIT_INT = 32; | |
41 | /** 32 bits to a float */ | |
42 | public static final int BIT_FLOAT = 32; | |
43 | /** 64 bits to a long */ | |
44 | public static final int BIT_LONG = 64; | |
45 | ||
46 | // ------------------------------------------------------------------------ | |
47 | // Attributes | |
48 | // ------------------------------------------------------------------------ | |
49 | ||
50 | private ByteBuffer buf; | |
47ca6c05 | 51 | private long pos; |
486efb2e AM |
52 | private ByteOrder byteOrder; |
53 | ||
54 | // ------------------------------------------------------------------------ | |
55 | // Constructors | |
56 | // ------------------------------------------------------------------------ | |
57 | /** | |
74e4b6b9 | 58 | * Default constructor, makes a big-endian buffer |
486efb2e AM |
59 | */ |
60 | public BitBuffer() { | |
61 | this(null, ByteOrder.BIG_ENDIAN); | |
62 | } | |
63 | ||
64 | /** | |
74e4b6b9 | 65 | * Constructor, makes a big-endian buffer |
486efb2e AM |
66 | * |
67 | * @param buf | |
68 | * the bytebuffer to read | |
69 | */ | |
70 | public BitBuffer(ByteBuffer buf) { | |
71 | this(buf, ByteOrder.BIG_ENDIAN); | |
72 | } | |
73 | ||
74 | /** | |
74e4b6b9 | 75 | * Constructor that is fully parameterizable |
486efb2e AM |
76 | * |
77 | * @param buf | |
78 | * the buffer to read | |
79 | * @param order | |
74e4b6b9 | 80 | * the byte order (big-endian, little-endian, network?) |
486efb2e AM |
81 | */ |
82 | public BitBuffer(ByteBuffer buf, ByteOrder order) { | |
83 | setByteBuffer(buf); | |
84 | setByteOrder(order); | |
85 | position(0); | |
86 | } | |
87 | ||
88 | // ------------------------------------------------------------------------ | |
89 | // 'Get' operations on buffer | |
90 | // ------------------------------------------------------------------------ | |
91 | ||
92 | /** | |
93 | * Relative <i>get</i> method for reading 32-bit integer. | |
94 | * | |
95 | * Reads next four bytes from the current bit position according to current | |
96 | * byte order. | |
97 | * | |
98 | * @return The int value read from the buffer | |
db8e8f7d AM |
99 | * @throws CTFReaderException |
100 | * An error occurred reading the data. When the buffer is read | |
101 | * beyond its end, this exception will be raised. | |
486efb2e | 102 | */ |
db8e8f7d | 103 | public int getInt() throws CTFReaderException { |
0594c61c | 104 | return getInt(BIT_INT, true); |
486efb2e AM |
105 | } |
106 | ||
107 | /** | |
108 | * Relative <i>get</i> method for reading integer of <i>length</i> bits. | |
109 | * | |
110 | * Reads <i>length</i> bits starting at the current position. The result is | |
111 | * signed extended if <i>signed</i> is true. The current position is | |
112 | * increased of <i>length</i> bits. | |
113 | * | |
114 | * @param length | |
115 | * The length in bits of this integer | |
116 | * @param signed | |
117 | * The sign extended flag | |
118 | * @return The int value read from the buffer | |
db8e8f7d AM |
119 | * @throws CTFReaderException |
120 | * An error occurred reading the data. When the buffer is read | |
121 | * beyond its end, this exception will be raised. | |
486efb2e | 122 | */ |
db8e8f7d | 123 | public int getInt(int length, boolean signed) throws CTFReaderException { |
74e4b6b9 EB |
124 | |
125 | /* Nothing to read. */ | |
486efb2e AM |
126 | if (length == 0) { |
127 | return 0; | |
128 | } | |
74e4b6b9 EB |
129 | |
130 | /* Validate that the buffer has enough bits. */ | |
131 | if (!canRead(length)) { | |
db8e8f7d AM |
132 | throw new CTFReaderException("Cannot read the integer, " + //$NON-NLS-1$ |
133 | "the buffer does not have enough remaining space. " + //$NON-NLS-1$ | |
134 | "Requested:" + length); //$NON-NLS-1$ | |
74e4b6b9 EB |
135 | } |
136 | ||
137 | /* Get the value from the byte buffer. */ | |
138 | int val = 0; | |
486efb2e AM |
139 | boolean gotIt = false; |
140 | ||
74e4b6b9 EB |
141 | /* Try a fast read when the position is byte-aligned by using the */ |
142 | /* native methods of ByteBuffer. */ | |
486efb2e AM |
143 | if (this.pos % BitBuffer.BIT_CHAR == 0) { |
144 | switch (length) { | |
145 | case BitBuffer.BIT_CHAR: | |
146 | // Byte | |
74e4b6b9 EB |
147 | val = this.buf.get((int) (this.pos / 8)); |
148 | if (!signed) { | |
149 | val = val & 0xff; | |
486efb2e AM |
150 | } |
151 | gotIt = true; | |
152 | break; | |
153 | ||
154 | case BitBuffer.BIT_SHORT: | |
155 | // Word | |
74e4b6b9 EB |
156 | val = this.buf.getShort((int) (this.pos / 8)); |
157 | if (!signed) { | |
158 | val = val & 0xffff; | |
486efb2e AM |
159 | } |
160 | gotIt = true; | |
161 | break; | |
162 | ||
163 | case BitBuffer.BIT_INT: | |
164 | // Double word | |
47ca6c05 | 165 | val = this.buf.getInt((int) (this.pos / 8)); |
486efb2e AM |
166 | gotIt = true; |
167 | break; | |
168 | ||
169 | default: | |
170 | break; | |
171 | } | |
172 | } | |
74e4b6b9 EB |
173 | |
174 | /* When not byte-aligned, fall-back to a general decoder. */ | |
486efb2e AM |
175 | if (!gotIt) { |
176 | // Nothing read yet: use longer methods | |
177 | if (this.byteOrder == ByteOrder.LITTLE_ENDIAN) { | |
178 | val = getIntLE(this.pos, length, signed); | |
179 | } else { | |
180 | val = getIntBE(this.pos, length, signed); | |
181 | } | |
182 | } | |
183 | this.pos += length; | |
184 | ||
185 | return val; | |
186 | } | |
187 | ||
47ca6c05 | 188 | private int getIntBE(long index, int length, boolean signed) { |
486efb2e | 189 | assert ((length > 0) && (length <= BIT_INT)); |
47ca6c05 SM |
190 | long end = index + length; |
191 | int startByte = (int) (index / BIT_CHAR); | |
192 | int endByte = (int) ((end + (BIT_CHAR - 1)) / BIT_CHAR); | |
486efb2e AM |
193 | int currByte, lshift, cshift, mask, cmask, cache; |
194 | int value = 0; | |
195 | ||
196 | currByte = startByte; | |
197 | cache = this.buf.get(currByte) & 0xFF; | |
198 | boolean isNeg = (cache & (1 << (BIT_CHAR - (index % BIT_CHAR) - 1))) != 0; | |
199 | if (signed && isNeg) { | |
200 | value = ~0; | |
201 | } | |
202 | if (startByte == (endByte - 1)) { | |
203 | cmask = cache >>> ((BIT_CHAR - (end % BIT_CHAR)) % BIT_CHAR); | |
204 | if (((length) % BIT_CHAR) > 0) { | |
205 | mask = ~((~0) << length); | |
206 | cmask &= mask; | |
207 | } | |
208 | value <<= length; | |
209 | value |= cmask; | |
210 | return value; | |
211 | } | |
47ca6c05 | 212 | cshift = (int) (index % BIT_CHAR); |
486efb2e AM |
213 | if (cshift > 0) { |
214 | mask = ~((~0) << (BIT_CHAR - cshift)); | |
215 | cmask = cache & mask; | |
216 | lshift = BIT_CHAR - cshift; | |
217 | value <<= lshift; | |
218 | value |= cmask; | |
486efb2e AM |
219 | currByte++; |
220 | } | |
221 | for (; currByte < (endByte - 1); currByte++) { | |
222 | value <<= BIT_CHAR; | |
223 | value |= this.buf.get(currByte) & 0xFF; | |
224 | } | |
47ca6c05 | 225 | lshift = (int) (end % BIT_CHAR); |
486efb2e AM |
226 | if (lshift > 0) { |
227 | mask = ~((~0) << lshift); | |
228 | cmask = this.buf.get(currByte) & 0xFF; | |
229 | cmask >>>= BIT_CHAR - lshift; | |
230 | cmask &= mask; | |
231 | value <<= lshift; | |
232 | value |= cmask; | |
233 | } else { | |
234 | value <<= BIT_CHAR; | |
235 | value |= this.buf.get(currByte) & 0xFF; | |
236 | } | |
237 | return value; | |
238 | } | |
239 | ||
47ca6c05 | 240 | private int getIntLE(long index, int length, boolean signed) { |
486efb2e | 241 | assert ((length > 0) && (length <= BIT_INT)); |
47ca6c05 SM |
242 | long end = index + length; |
243 | int startByte = (int) (index / BIT_CHAR); | |
244 | int endByte = (int) ((end + (BIT_CHAR - 1)) / BIT_CHAR); | |
486efb2e AM |
245 | int currByte, lshift, cshift, mask, cmask, cache, mod; |
246 | int value = 0; | |
247 | ||
248 | currByte = endByte - 1; | |
249 | cache = buf.get(currByte) & 0xFF; | |
47ca6c05 | 250 | mod = (int) (end % BIT_CHAR); |
486efb2e AM |
251 | lshift = (mod > 0) ? mod : BIT_CHAR; |
252 | boolean isNeg = (cache & (1 << (lshift - 1))) != 0; | |
253 | if (signed && isNeg) { | |
254 | value = ~0; | |
255 | } | |
256 | if (startByte == (endByte - 1)) { | |
257 | cmask = cache >>> (index % BIT_CHAR); | |
258 | if (((length) % BIT_CHAR) > 0) { | |
259 | mask = ~((~0) << length); | |
260 | cmask &= mask; | |
261 | } | |
262 | value <<= length; | |
263 | value |= cmask; | |
264 | return value; | |
265 | } | |
47ca6c05 | 266 | cshift = (int) (end % BIT_CHAR); |
486efb2e AM |
267 | if (cshift > 0) { |
268 | mask = ~((~0) << cshift); | |
269 | cmask = cache & mask; | |
270 | value <<= cshift; | |
271 | value |= cmask; | |
486efb2e AM |
272 | currByte--; |
273 | } | |
274 | for (; currByte >= (startByte + 1); currByte--) { | |
275 | value <<= BIT_CHAR; | |
276 | value |= buf.get(currByte) & 0xFF; | |
277 | } | |
47ca6c05 | 278 | lshift = (int) (index % BIT_CHAR); |
486efb2e AM |
279 | if (lshift > 0) { |
280 | mask = ~((~0) << (BIT_CHAR - lshift)); | |
281 | cmask = buf.get(currByte) & 0xFF; | |
282 | cmask >>>= lshift; | |
283 | cmask &= mask; | |
284 | value <<= (BIT_CHAR - lshift); | |
285 | value |= cmask; | |
286 | } else { | |
287 | value <<= BIT_CHAR; | |
288 | value |= buf.get(currByte) & 0xFF; | |
289 | } | |
290 | return value; | |
291 | } | |
292 | ||
293 | // ------------------------------------------------------------------------ | |
294 | // 'Put' operations on buffer | |
295 | // ------------------------------------------------------------------------ | |
296 | ||
297 | /** | |
298 | * Relative <i>put</i> method to write signed 32-bit integer. | |
299 | * | |
300 | * Write four bytes starting from current bit position in the buffer | |
301 | * according to the current byte order. The current position is increased of | |
302 | * <i>length</i> bits. | |
303 | * | |
304 | * @param value | |
305 | * The int value to write | |
db8e8f7d AM |
306 | * @throws CTFReaderException |
307 | * An error occurred writing the data. If the buffer is written | |
308 | * beyond its end, this exception will be raised. | |
486efb2e | 309 | */ |
db8e8f7d | 310 | public void putInt(int value) throws CTFReaderException { |
486efb2e AM |
311 | putInt(BIT_INT, value); |
312 | } | |
313 | ||
314 | /** | |
315 | * Relative <i>put</i> method to write <i>length</i> bits integer. | |
316 | * | |
317 | * Writes <i>length</i> lower-order bits from the provided <i>value</i>, | |
318 | * starting from current bit position in the buffer. Sequential bytes are | |
319 | * written according to the current byte order. The sign bit is carried to | |
320 | * the MSB if signed is true. The sign bit is included in <i>length</i>. The | |
321 | * current position is increased of <i>length</i>. | |
322 | * | |
323 | * @param length | |
324 | * The number of bits to write | |
325 | * @param value | |
326 | * The value to write | |
db8e8f7d AM |
327 | * @throws CTFReaderException |
328 | * An error occurred writing the data. If the buffer is written | |
329 | * beyond its end, this exception will be raised. | |
486efb2e | 330 | */ |
db8e8f7d | 331 | public void putInt(int length, int value) throws CTFReaderException { |
47ca6c05 | 332 | final long curPos = this.pos; |
486efb2e AM |
333 | |
334 | if (!canRead(length)) { | |
db8e8f7d AM |
335 | throw new CTFReaderException("Cannot write to bitbuffer, " //$NON-NLS-1$ |
336 | + "insufficient space. Requested: " + length); //$NON-NLS-1$ | |
486efb2e AM |
337 | } |
338 | if (length == 0) { | |
339 | return; | |
340 | } | |
341 | if (this.byteOrder == ByteOrder.LITTLE_ENDIAN) { | |
342 | putIntLE(curPos, length, value); | |
343 | } else { | |
344 | putIntBE(curPos, length, value); | |
345 | } | |
346 | this.pos += length; | |
347 | } | |
348 | ||
47ca6c05 | 349 | private void putIntBE(long index, int length, int value) { |
486efb2e | 350 | assert ((length > 0) && (length <= BIT_INT)); |
47ca6c05 SM |
351 | long end = index + length; |
352 | int startByte = (int) (index / BIT_CHAR); | |
353 | int endByte = (int) ((end + (BIT_CHAR - 1)) / BIT_CHAR); | |
486efb2e AM |
354 | int currByte, lshift, cshift, mask, cmask; |
355 | int correctedValue = value; | |
356 | ||
357 | /* | |
358 | * mask v high bits. Works for unsigned and two complement signed | |
359 | * numbers which value do not overflow on length bits. | |
360 | */ | |
361 | ||
362 | if (length < BIT_INT) { | |
363 | correctedValue &= ~(~0 << length); | |
364 | } | |
365 | ||
366 | /* sub byte */ | |
367 | if (startByte == (endByte - 1)) { | |
47ca6c05 | 368 | lshift = (int) ((BIT_CHAR - (end % BIT_CHAR)) % BIT_CHAR); |
486efb2e AM |
369 | mask = ~((~0) << lshift); |
370 | if ((index % BIT_CHAR) > 0) { | |
371 | mask |= (~(0)) << (BIT_CHAR - (index % BIT_CHAR)); | |
372 | } | |
373 | cmask = correctedValue << lshift; | |
374 | /* | |
74e4b6b9 EB |
375 | * low bits are cleared because of left-shift and high bits are |
376 | * already cleared | |
486efb2e AM |
377 | */ |
378 | cmask &= ~mask; | |
379 | int b = this.buf.get(startByte) & 0xFF; | |
380 | this.buf.put(startByte, (byte) ((b & mask) | cmask)); | |
381 | return; | |
382 | } | |
383 | ||
384 | /* head byte contains MSB */ | |
385 | currByte = endByte - 1; | |
47ca6c05 | 386 | cshift = (int) (end % BIT_CHAR); |
486efb2e AM |
387 | if (cshift > 0) { |
388 | lshift = BIT_CHAR - cshift; | |
389 | mask = ~((~0) << lshift); | |
390 | cmask = correctedValue << lshift; | |
391 | cmask &= ~mask; | |
392 | int b = this.buf.get(currByte) & 0xFF; | |
393 | this.buf.put(currByte, (byte) ((b & mask) | cmask)); | |
394 | correctedValue >>>= cshift; | |
486efb2e AM |
395 | currByte--; |
396 | } | |
397 | ||
398 | /* middle byte(s) */ | |
399 | for (; currByte >= (startByte + 1); currByte--) { | |
400 | this.buf.put(currByte, (byte) correctedValue); | |
401 | correctedValue >>>= BIT_CHAR; | |
402 | } | |
403 | /* end byte contains LSB */ | |
404 | if ((index % BIT_CHAR) > 0) { | |
405 | mask = (~0) << (BIT_CHAR - (index % BIT_CHAR)); | |
406 | cmask = correctedValue & ~mask; | |
407 | int b = this.buf.get(currByte) & 0xFF; | |
408 | this.buf.put(currByte, (byte) ((b & mask) | cmask)); | |
409 | } else { | |
410 | this.buf.put(currByte, (byte) correctedValue); | |
411 | } | |
412 | } | |
413 | ||
47ca6c05 | 414 | private void putIntLE(long index, int length, int value) { |
486efb2e | 415 | assert ((length > 0) && (length <= BIT_INT)); |
47ca6c05 SM |
416 | long end = index + length; |
417 | int startByte = (int) (index / BIT_CHAR); | |
418 | int endByte = (int) ((end + (BIT_CHAR - 1)) / BIT_CHAR); | |
486efb2e AM |
419 | int currByte, lshift, cshift, mask, cmask; |
420 | int correctedValue = value; | |
421 | ||
422 | /* | |
423 | * mask v high bits. Works for unsigned and two complement signed | |
424 | * numbers which value do not overflow on length bits. | |
425 | */ | |
426 | ||
427 | if (length < BIT_INT) { | |
428 | correctedValue &= ~(~0 << length); | |
429 | } | |
430 | ||
431 | /* sub byte */ | |
432 | if (startByte == (endByte - 1)) { | |
47ca6c05 | 433 | lshift = (int) (index % BIT_CHAR); |
486efb2e AM |
434 | mask = ~((~0) << lshift); |
435 | if ((end % BIT_CHAR) > 0) { | |
436 | mask |= (~(0)) << (end % BIT_CHAR); | |
437 | } | |
438 | cmask = correctedValue << lshift; | |
439 | /* | |
74e4b6b9 EB |
440 | * low bits are cleared because of left-shift and high bits are |
441 | * already cleared | |
486efb2e AM |
442 | */ |
443 | cmask &= ~mask; | |
444 | int b = this.buf.get(startByte) & 0xFF; | |
445 | this.buf.put(startByte, (byte) ((b & mask) | cmask)); | |
446 | return; | |
447 | } | |
448 | ||
449 | /* head byte */ | |
450 | currByte = startByte; | |
47ca6c05 | 451 | cshift = (int) (index % BIT_CHAR); |
486efb2e AM |
452 | if (cshift > 0) { |
453 | mask = ~((~0) << cshift); | |
454 | cmask = correctedValue << cshift; | |
455 | cmask &= ~mask; | |
456 | int b = this.buf.get(currByte) & 0xFF; | |
457 | this.buf.put(currByte, (byte) ((b & mask) | cmask)); | |
458 | correctedValue >>>= BIT_CHAR - cshift; | |
486efb2e AM |
459 | currByte++; |
460 | } | |
461 | ||
462 | /* middle byte(s) */ | |
463 | for (; currByte < (endByte - 1); currByte++) { | |
464 | this.buf.put(currByte, (byte) correctedValue); | |
465 | correctedValue >>>= BIT_CHAR; | |
466 | } | |
467 | /* end byte */ | |
468 | if ((end % BIT_CHAR) > 0) { | |
469 | mask = (~0) << (end % BIT_CHAR); | |
470 | cmask = correctedValue & ~mask; | |
471 | int b = this.buf.get(currByte) & 0xFF; | |
472 | this.buf.put(currByte, (byte) ((b & mask) | cmask)); | |
473 | } else { | |
474 | this.buf.put(currByte, (byte) correctedValue); | |
475 | } | |
476 | } | |
477 | ||
478 | // ------------------------------------------------------------------------ | |
479 | // Buffer attributes handling | |
480 | // ------------------------------------------------------------------------ | |
481 | ||
482 | /** | |
483 | * Can this buffer be read for thus amount of bits? | |
484 | * | |
485 | * @param length | |
486 | * the length in bits to read | |
487 | * @return does the buffer have enough room to read the next "length" | |
488 | */ | |
489 | public boolean canRead(int length) { | |
490 | if (this.buf == null) { | |
491 | return false; | |
492 | } | |
493 | ||
47ca6c05 | 494 | if ((this.pos + length) > (((long) this.buf.capacity()) * BIT_CHAR)) { |
486efb2e AM |
495 | return false; |
496 | } | |
497 | return true; | |
498 | } | |
499 | ||
500 | /** | |
501 | * Sets the order of the buffer. | |
502 | * | |
503 | * @param order | |
504 | * The order of the buffer. | |
505 | */ | |
506 | public void setByteOrder(ByteOrder order) { | |
507 | this.byteOrder = order; | |
508 | if (this.buf != null) { | |
509 | this.buf.order(order); | |
510 | } | |
511 | } | |
512 | ||
513 | /** | |
514 | * Sets the order of the buffer. | |
515 | * | |
516 | * @return The order of the buffer. | |
517 | */ | |
518 | public ByteOrder getByteOrder() { | |
519 | return this.byteOrder; | |
520 | } | |
521 | ||
522 | /** | |
523 | * Sets the position in the buffer. | |
524 | * | |
525 | * @param newPosition | |
526 | * The new position of the buffer. | |
527 | */ | |
47ca6c05 | 528 | public void position(long newPosition) { |
486efb2e AM |
529 | this.pos = newPosition; |
530 | } | |
531 | ||
532 | /** | |
533 | * | |
534 | * Sets the position in the buffer. | |
535 | * | |
536 | * @return order The position of the buffer. | |
537 | */ | |
47ca6c05 | 538 | public long position() { |
486efb2e AM |
539 | return this.pos; |
540 | } | |
541 | ||
542 | /** | |
543 | * Sets the byte buffer | |
544 | * | |
545 | * @param buf | |
546 | * the byte buffer | |
547 | */ | |
548 | public void setByteBuffer(ByteBuffer buf) { | |
549 | this.buf = buf; | |
550 | if (buf != null) { | |
551 | this.buf.order(this.byteOrder); | |
552 | } | |
553 | clear(); | |
554 | } | |
555 | ||
556 | /** | |
557 | * Gets the byte buffer | |
558 | * | |
559 | * @return The byte buffer | |
560 | */ | |
561 | public ByteBuffer getByteBuffer() { | |
562 | return this.buf; | |
563 | } | |
564 | ||
565 | /** | |
74e4b6b9 | 566 | * Resets the bitbuffer. |
486efb2e AM |
567 | */ |
568 | public void clear() { | |
569 | position(0); | |
570 | ||
571 | if (this.buf == null) { | |
572 | return; | |
573 | } | |
574 | this.buf.clear(); | |
575 | } | |
576 | ||
577 | } |