1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.buffer;
17
18 import java.io.IOException;
19 import java.io.InputStream;
20 import java.io.OutputStream;
21 import java.nio.ByteBuffer;
22 import java.nio.ByteOrder;
23 import java.nio.channels.GatheringByteChannel;
24 import java.nio.channels.ScatteringByteChannel;
25 import java.nio.charset.Charset;
26 import java.nio.charset.UnsupportedCharsetException;
27
28 /**
29 * A random and sequential accessible sequence of zero or more bytes (octets).
30 * This interface provides an abstract view for one or more primitive byte
31 * arrays ({@code byte[]}) and {@linkplain ByteBuffer NIO buffers}.
32 *
33 * <h3>Creation of a buffer</h3>
34 *
35 * It is recommended to create a new buffer using the helper methods in
36 * {@link ChannelBuffers} rather than calling an individual implementation's
37 * constructor.
38 *
39 * <h3>Random Access Indexing</h3>
40 *
41 * Just like an ordinary primitive byte array, {@link ChannelBuffer} uses
42 * <a href="http://en.wikipedia.org/wiki/Zero-based_numbering">zero-based indexing</a>.
43 * It means the index of the first byte is always {@code 0} and the index of the last byte is
44 * always {@link #capacity() capacity - 1}. For example, to iterate all bytes of a buffer, you
45 * can do the following, regardless of its internal implementation:
46 *
47 * <pre>
48 * {@link ChannelBuffer} buffer = ...;
49 * for (int i = 0; i < buffer.capacity(); i ++) {
50 * byte b = buffer.getByte(i);
51 * System.out.println((char) b);
52 * }
53 * </pre>
54 *
55 * <h3>Sequential Access Indexing</h3>
56 *
57 * {@link ChannelBuffer} provides two pointer variables to support sequential
58 * read and write operations - {@link #readerIndex() readerIndex} for a read
59 * operation and {@link #writerIndex() writerIndex} for a write operation
60 * respectively. The following diagram shows how a buffer is segmented into
61 * three areas by the two pointers:
62 *
63 * <pre>
64 * +-------------------+------------------+------------------+
65 * | discardable bytes | readable bytes | writable bytes |
66 * | | (CONTENT) | |
67 * +-------------------+------------------+------------------+
68 * | | | |
69 * 0 <= readerIndex <= writerIndex <= capacity
70 * </pre>
71 *
72 * <h4>Readable bytes (the actual content)</h4>
73 *
74 * This segment is where the actual data is stored. Any operation whose name
75 * starts with {@code read} or {@code skip} will get or skip the data at the
76 * current {@link #readerIndex() readerIndex} and increase it by the number of
77 * read bytes. If the argument of the read operation is also a
78 * {@link ChannelBuffer} and no destination index is specified, the specified
79 * buffer's {@link #readerIndex() readerIndex} is increased together.
80 * <p>
81 * If there's not enough content left, {@link IndexOutOfBoundsException} is
82 * raised. The default value of newly allocated, wrapped or copied buffer's
83 * {@link #readerIndex() readerIndex} is {@code 0}.
84 *
85 * <pre>
86 * // Iterates the readable bytes of a buffer.
87 * {@link ChannelBuffer} buffer = ...;
88 * while (buffer.readable()) {
89 * System.out.println(buffer.readByte());
90 * }
91 * </pre>
92 *
93 * <h4>Writable bytes</h4>
94 *
95 * This segment is a undefined space which needs to be filled. Any operation
96 * whose name ends with {@code write} will write the data at the current
97 * {@link #writerIndex() writerIndex} and increase it by the number of written
98 * bytes. If the argument of the write operation is also a {@link ChannelBuffer},
99 * and no source index is specified, the specified buffer's
100 * {@link #readerIndex() readerIndex} is increased together.
101 * <p>
102 * If there's not enough writable bytes left, {@link IndexOutOfBoundsException}
103 * is raised. The default value of newly allocated buffer's
104 * {@link #writerIndex() writerIndex} is {@code 0}. The default value of
105 * wrapped or copied buffer's {@link #writerIndex() writerIndex} is the
106 * {@link #capacity() capacity} of the buffer.
107 *
108 * <pre>
109 * // Fills the writable bytes of a buffer with random integers.
110 * {@link ChannelBuffer} buffer = ...;
111 * while (buffer.writableBytes() >= 4) {
112 * buffer.writeInt(random.nextInt());
113 * }
114 * </pre>
115 *
116 * <h4>Discardable bytes</h4>
117 *
118 * This segment contains the bytes which were read already by a read operation.
119 * Initially, the size of this segment is {@code 0}, but its size increases up
120 * to the {@link #writerIndex() writerIndex} as read operations are executed.
121 * The read bytes can be discarded by calling {@link #discardReadBytes()} to
122 * reclaim unused area as depicted by the following diagram:
123 *
124 * <pre>
125 * BEFORE discardReadBytes()
126 *
127 * +-------------------+------------------+------------------+
128 * | discardable bytes | readable bytes | writable bytes |
129 * +-------------------+------------------+------------------+
130 * | | | |
131 * 0 <= readerIndex <= writerIndex <= capacity
132 *
133 *
134 * AFTER discardReadBytes()
135 *
136 * +------------------+--------------------------------------+
137 * | readable bytes | writable bytes (got more space) |
138 * +------------------+--------------------------------------+
139 * | | |
140 * readerIndex (0) <= writerIndex (decreased) <= capacity
141 * </pre>
142 *
143 * Please note that there is no guarantee about the content of writable bytes
144 * after calling {@link #discardReadBytes()}. The writable bytes will not be
145 * moved in most cases and could even be filled with completely different data
146 * depending on the underlying buffer implementation.
147 *
148 * <h4>Clearing the buffer indexes</h4>
149 *
150 * You can set both {@link #readerIndex() readerIndex} and
151 * {@link #writerIndex() writerIndex} to {@code 0} by calling {@link #clear()}.
152 * It does not clear the buffer content (e.g. filling with {@code 0}) but just
153 * clears the two pointers. Please also note that the semantic of this
154 * operation is different from {@link ByteBuffer#clear()}.
155 *
156 * <pre>
157 * BEFORE clear()
158 *
159 * +-------------------+------------------+------------------+
160 * | discardable bytes | readable bytes | writable bytes |
161 * +-------------------+------------------+------------------+
162 * | | | |
163 * 0 <= readerIndex <= writerIndex <= capacity
164 *
165 *
166 * AFTER clear()
167 *
168 * +---------------------------------------------------------+
169 * | writable bytes (got more space) |
170 * +---------------------------------------------------------+
171 * | |
172 * 0 = readerIndex = writerIndex <= capacity
173 * </pre>
174 *
175 * <h3>Search operations</h3>
176 *
177 * Various {@link #indexOf(int, int, byte)} methods help you locate an index of
178 * a value which meets a certain criteria. Complicated dynamic sequential
179 * search can be done with {@link ChannelBufferIndexFinder} as well as simple
180 * static single byte search.
181 * <p>
182 * If you are decoding variable length data such as NUL-terminated string, you
183 * will find {@link #bytesBefore(byte)} also useful.
184 *
185 * <h3>Mark and reset</h3>
186 *
187 * There are two marker indexes in every buffer. One is for storing
188 * {@link #readerIndex() readerIndex} and the other is for storing
189 * {@link #writerIndex() writerIndex}. You can always reposition one of the
190 * two indexes by calling a reset method. It works in a similar fashion to
191 * the mark and reset methods in {@link InputStream} except that there's no
192 * {@code readlimit}.
193 *
194 * <h3>Derived buffers</h3>
195 *
196 * You can create a view of an existing buffer by calling either
197 * {@link #duplicate()}, {@link #slice()} or {@link #slice(int, int)}.
198 * A derived buffer will have an independent {@link #readerIndex() readerIndex},
199 * {@link #writerIndex() writerIndex} and marker indexes, while it shares
200 * other internal data representation, just like a NIO buffer does.
201 * <p>
202 * In case a completely fresh copy of an existing buffer is required, please
203 * call {@link #copy()} method instead.
204 *
205 * <h3>Conversion to existing JDK types</h3>
206 *
207 * <h4>Byte array</h4>
208 *
209 * If a {@link ChannelBuffer} is backed by a byte array (i.e. {@code byte[]}),
210 * you can access it directly via the {@link #array()} method. To determine
211 * if a buffer is backed by a byte array, {@link #hasArray()} should be used.
212 *
213 * <h4>NIO Buffers</h4>
214 *
215 * Various {@link #toByteBuffer()} and {@link #toByteBuffers()} methods convert
216 * a {@link ChannelBuffer} into one or more NIO buffers. These methods avoid
217 * buffer allocation and memory copy whenever possible, but there's no
218 * guarantee that memory copy will not be involved.
219 *
220 * <h4>Strings</h4>
221 *
222 * Various {@link #toString(String)} methods convert a {@link ChannelBuffer}
223 * into a {@link String}. Please note that {@link #toString()} is not a
224 * conversion method.
225 *
226 * <h4>I/O Streams</h4>
227 *
228 * Please refer to {@link ChannelBufferInputStream} and
229 * {@link ChannelBufferOutputStream}.
230 *
231 * @apiviz.landmark
232 */
233 public interface ChannelBuffer extends Comparable<ChannelBuffer> {
234
235 /**
236 * Returns the factory which creates a {@link ChannelBuffer} whose
237 * type and default {@link ByteOrder} are same with this buffer.
238 */
239 ChannelBufferFactory factory();
240
241 /**
242 * Returns the number of bytes (octets) this buffer can contain.
243 */
244 int capacity();
245
246 /**
247 * Returns the <a href="http://en.wikipedia.org/wiki/Endianness">endianness</a>
248 * of this buffer.
249 */
250 ByteOrder order();
251
252 /**
253 * Returns {@code true} if and only if this buffer is backed by an
254 * NIO direct buffer.
255 */
256 boolean isDirect();
257
258 /**
259 * Returns the {@code readerIndex} of this buffer.
260 */
261 int readerIndex();
262
263 /**
264 * Sets the {@code readerIndex} of this buffer.
265 *
266 * @throws IndexOutOfBoundsException
267 * if the specified {@code readerIndex} is
268 * less than {@code 0} or
269 * greater than {@code this.writerIndex}
270 */
271 void readerIndex(int readerIndex);
272
273 /**
274 * Returns the {@code writerIndex} of this buffer.
275 */
276 int writerIndex();
277
278 /**
279 * Sets the {@code writerIndex} of this buffer.
280 *
281 * @throws IndexOutOfBoundsException
282 * if the specified {@code writerIndex} is
283 * less than {@code this.readerIndex} or
284 * greater than {@code this.capacity}
285 */
286 void writerIndex(int writerIndex);
287
288 /**
289 * Sets the {@code readerIndex} and {@code writerIndex} of this buffer
290 * in one shot. This method is useful when you have to worry about the
291 * invocation order of {@link #readerIndex(int)} and {@link #writerIndex(int)}
292 * methods. For example, the following code will fail:
293 *
294 * <pre>
295 * // Create a buffer whose readerIndex, writerIndex and capacity are
296 * // 0, 0 and 8 respectively.
297 * {@link ChannelBuffer} buf = {@link ChannelBuffers}.buffer(8);
298 *
299 * // IndexOutOfBoundsException is thrown because the specified
300 * // readerIndex (2) cannot be greater than the current writerIndex (0).
301 * buf.readerIndex(2);
302 * buf.writerIndex(4);
303 * </pre>
304 *
305 * The following code will also fail:
306 *
307 * <pre>
308 * // Create a buffer whose readerIndex, writerIndex and capacity are
309 * // 0, 8 and 8 respectively.
310 * {@link ChannelBuffer} buf = {@link ChannelBuffers}.wrappedBuffer(new byte[8]);
311 *
312 * // readerIndex becomes 8.
313 * buf.readLong();
314 *
315 * // IndexOutOfBoundsException is thrown because the specified
316 * // writerIndex (4) cannot be less than the current readerIndex (8).
317 * buf.writerIndex(4);
318 * buf.readerIndex(2);
319 * </pre>
320 *
321 * By contrast, this method guarantees that it never
322 * throws an {@link IndexOutOfBoundsException} as long as the specified
323 * indexes meet basic constraints, regardless what the current index
324 * values of the buffer are:
325 *
326 * <pre>
327 * // No matter what the current state of the buffer is, the following
328 * // call always succeeds as long as the capacity of the buffer is not
329 * // less than 4.
330 * buf.setIndex(2, 4);
331 * </pre>
332 *
333 * @throws IndexOutOfBoundsException
334 * if the specified {@code readerIndex} is less than 0,
335 * if the specified {@code writerIndex} is less than the specified
336 * {@code readerIndex} or if the specified {@code writerIndex} is
337 * greater than {@code this.capacity}
338 */
339 void setIndex(int readerIndex, int writerIndex);
340
341 /**
342 * Returns the number of readable bytes which is equal to
343 * {@code (this.writerIndex - this.readerIndex)}.
344 */
345 int readableBytes();
346
347 /**
348 * Returns the number of writable bytes which is equal to
349 * {@code (this.capacity - this.writerIndex)}.
350 */
351 int writableBytes();
352
353 /**
354 * Returns {@code true}
355 * if and only if {@code (this.writerIndex - this.readerIndex)} is greater
356 * than {@code 0}.
357 */
358 boolean readable();
359
360 /**
361 * Returns {@code true}
362 * if and only if {@code (this.capacity - this.writerIndex)} is greater
363 * than {@code 0}.
364 */
365 boolean writable();
366
367 /**
368 * Sets the {@code readerIndex} and {@code writerIndex} of this buffer to
369 * {@code 0}.
370 * This method is identical to {@link #setIndex(int, int) setIndex(0, 0)}.
371 * <p>
372 * Please note that the behavior of this method is different
373 * from that of NIO buffer, which sets the {@code limit} to
374 * the {@code capacity} of the buffer.
375 */
376 void clear();
377
378 /**
379 * Marks the current {@code readerIndex} in this buffer. You can
380 * reposition the current {@code readerIndex} to the marked
381 * {@code readerIndex} by calling {@link #resetReaderIndex()}.
382 * The initial value of the marked {@code readerIndex} is {@code 0}.
383 */
384 void markReaderIndex();
385
386 /**
387 * Repositions the current {@code readerIndex} to the marked
388 * {@code readerIndex} in this buffer.
389 *
390 * @throws IndexOutOfBoundsException
391 * if the current {@code writerIndex} is less than the marked
392 * {@code readerIndex}
393 */
394 void resetReaderIndex();
395
396 /**
397 * Marks the current {@code writerIndex} in this buffer. You can
398 * reposition the current {@code writerIndex} to the marked
399 * {@code writerIndex} by calling {@link #resetWriterIndex()}.
400 * The initial value of the marked {@code writerIndex} is {@code 0}.
401 */
402 void markWriterIndex();
403
404 /**
405 * Repositions the current {@code writerIndex} to the marked
406 * {@code writerIndex} in this buffer.
407 *
408 * @throws IndexOutOfBoundsException
409 * if the current {@code readerIndex} is greater than the marked
410 * {@code writerIndex}
411 */
412 void resetWriterIndex();
413
414 /**
415 * Discards the bytes between the 0th index and {@code readerIndex}.
416 * It moves the bytes between {@code readerIndex} and {@code writerIndex}
417 * to the 0th index, and sets {@code readerIndex} and {@code writerIndex}
418 * to {@code 0} and {@code oldWriterIndex - oldReaderIndex} respectively.
419 * <p>
420 * Please refer to the class documentation for more detailed explanation.
421 */
422 void discardReadBytes();
423
424 /**
425 * Makes sure the number of {@linkplain #writableBytes() the writable bytes}
426 * is equal to or greater than the specified value. If there is enough
427 * writable bytes in this buffer, this method returns with no side effect.
428 * Otherwise:
429 * <ul>
430 * <li>a non-dynamic buffer will throw an {@link IndexOutOfBoundsException}.</li>
431 * <li>a dynamic buffer will expand its capacity so that the number of the
432 * {@link #writableBytes() writable bytes} becomes equal to or greater
433 * than the specified value. The expansion involves the reallocation of
434 * the internal buffer and consequently memory copy.</li>
435 * </ul>
436 *
437 * @param writableBytes
438 * the expected minimum number of writable bytes
439 * @throws IndexOutOfBoundsException
440 * if {@linkplain #writableBytes() the writable bytes} of this
441 * buffer is less than the specified value and if this buffer is
442 * not a dynamic buffer
443 */
444 void ensureWritableBytes(int writableBytes);
445
446 /**
447 * Gets a byte at the specified absolute {@code index} in this buffer.
448 * This method does not modify {@code readerIndex} or {@code writerIndex} of
449 * this buffer.
450 *
451 * @throws IndexOutOfBoundsException
452 * if the specified {@code index} is less than {@code 0} or
453 * {@code index + 1} is greater than {@code this.capacity}
454 */
455 byte getByte(int index);
456
457 /**
458 * Gets an unsigned byte at the specified absolute {@code index} in this
459 * buffer. This method does not modify {@code readerIndex} or
460 * {@code writerIndex} of this buffer.
461 *
462 * @throws IndexOutOfBoundsException
463 * if the specified {@code index} is less than {@code 0} or
464 * {@code index + 1} is greater than {@code this.capacity}
465 */
466 short getUnsignedByte(int index);
467
468 /**
469 * Gets a 16-bit short integer at the specified absolute {@code index} in
470 * this buffer. This method does not modify {@code readerIndex} or
471 * {@code writerIndex} of this buffer.
472 *
473 * @throws IndexOutOfBoundsException
474 * if the specified {@code index} is less than {@code 0} or
475 * {@code index + 2} is greater than {@code this.capacity}
476 */
477 short getShort(int index);
478
479 /**
480 * Gets an unsigned 16-bit short integer at the specified absolute
481 * {@code index} in this buffer. This method does not modify
482 * {@code readerIndex} or {@code writerIndex} of this buffer.
483 *
484 * @throws IndexOutOfBoundsException
485 * if the specified {@code index} is less than {@code 0} or
486 * {@code index + 2} is greater than {@code this.capacity}
487 */
488 int getUnsignedShort(int index);
489
490 /**
491 * Gets a 24-bit medium integer at the specified absolute {@code index} in
492 * this buffer. This method does not modify {@code readerIndex} or
493 * {@code writerIndex} of this buffer.
494 *
495 * @throws IndexOutOfBoundsException
496 * if the specified {@code index} is less than {@code 0} or
497 * {@code index + 3} is greater than {@code this.capacity}
498 */
499 int getMedium(int index);
500
501 /**
502 * Gets an unsigned 24-bit medium integer at the specified absolute
503 * {@code index} in this buffer. This method does not modify
504 * {@code readerIndex} or {@code writerIndex} of this buffer.
505 *
506 * @throws IndexOutOfBoundsException
507 * if the specified {@code index} is less than {@code 0} or
508 * {@code index + 3} is greater than {@code this.capacity}
509 */
510 int getUnsignedMedium(int index);
511
512 /**
513 * Gets a 32-bit integer at the specified absolute {@code index} in
514 * this buffer. This method does not modify {@code readerIndex} or
515 * {@code writerIndex} of this buffer.
516 *
517 * @throws IndexOutOfBoundsException
518 * if the specified {@code index} is less than {@code 0} or
519 * {@code index + 4} is greater than {@code this.capacity}
520 */
521 int getInt(int index);
522
523 /**
524 * Gets an unsigned 32-bit integer at the specified absolute {@code index}
525 * in this buffer. This method does not modify {@code readerIndex} or
526 * {@code writerIndex} of this buffer.
527 *
528 * @throws IndexOutOfBoundsException
529 * if the specified {@code index} is less than {@code 0} or
530 * {@code index + 4} is greater than {@code this.capacity}
531 */
532 long getUnsignedInt(int index);
533
534 /**
535 * Gets a 64-bit long integer at the specified absolute {@code index} in
536 * this buffer. This method does not modify {@code readerIndex} or
537 * {@code writerIndex} of this buffer.
538 *
539 * @throws IndexOutOfBoundsException
540 * if the specified {@code index} is less than {@code 0} or
541 * {@code index + 8} is greater than {@code this.capacity}
542 */
543 long getLong(int index);
544
545 /**
546 * Gets a 2-byte UTF-16 character at the specified absolute
547 * {@code index} in this buffer. This method does not modify
548 * {@code readerIndex} or {@code writerIndex} of this buffer.
549 *
550 * @throws IndexOutOfBoundsException
551 * if the specified {@code index} is less than {@code 0} or
552 * {@code index + 2} is greater than {@code this.capacity}
553 */
554 char getChar(int index);
555
556 /**
557 * Gets a 32-bit floating point number at the specified absolute
558 * {@code index} in this buffer. This method does not modify
559 * {@code readerIndex} or {@code writerIndex} of this buffer.
560 *
561 * @throws IndexOutOfBoundsException
562 * if the specified {@code index} is less than {@code 0} or
563 * {@code index + 4} is greater than {@code this.capacity}
564 */
565 float getFloat(int index);
566
567 /**
568 * Gets a 64-bit floating point number at the specified absolute
569 * {@code index} in this buffer. This method does not modify
570 * {@code readerIndex} or {@code writerIndex} of this buffer.
571 *
572 * @throws IndexOutOfBoundsException
573 * if the specified {@code index} is less than {@code 0} or
574 * {@code index + 8} is greater than {@code this.capacity}
575 */
576 double getDouble(int index);
577
578 /**
579 * Transfers this buffer's data to the specified destination starting at
580 * the specified absolute {@code index} until the destination becomes
581 * non-writable. This method is basically same with
582 * {@link #getBytes(int, ChannelBuffer, int, int)}, except that this
583 * method increases the {@code writerIndex} of the destination by the
584 * number of the transferred bytes while
585 * {@link #getBytes(int, ChannelBuffer, int, int)} does not.
586 * This method does not modify {@code readerIndex} or {@code writerIndex} of
587 * the source buffer (i.e. {@code this}).
588 *
589 * @throws IndexOutOfBoundsException
590 * if the specified {@code index} is less than {@code 0} or
591 * if {@code index + dst.writableBytes} is greater than
592 * {@code this.capacity}
593 */
594 void getBytes(int index, ChannelBuffer dst);
595
596 /**
597 * Transfers this buffer's data to the specified destination starting at
598 * the specified absolute {@code index}. This method is basically same
599 * with {@link #getBytes(int, ChannelBuffer, int, int)}, except that this
600 * method increases the {@code writerIndex} of the destination by the
601 * number of the transferred bytes while
602 * {@link #getBytes(int, ChannelBuffer, int, int)} does not.
603 * This method does not modify {@code readerIndex} or {@code writerIndex} of
604 * the source buffer (i.e. {@code this}).
605 *
606 * @param length the number of bytes to transfer
607 *
608 * @throws IndexOutOfBoundsException
609 * if the specified {@code index} is less than {@code 0},
610 * if {@code index + length} is greater than
611 * {@code this.capacity}, or
612 * if {@code length} is greater than {@code dst.writableBytes}
613 */
614 void getBytes(int index, ChannelBuffer dst, int length);
615
616 /**
617 * Transfers this buffer's data to the specified destination starting at
618 * the specified absolute {@code index}.
619 * This method does not modify {@code readerIndex} or {@code writerIndex}
620 * of both the source (i.e. {@code this}) and the destination.
621 *
622 * @param dstIndex the first index of the destination
623 * @param length the number of bytes to transfer
624 *
625 * @throws IndexOutOfBoundsException
626 * if the specified {@code index} is less than {@code 0},
627 * if the specified {@code dstIndex} is less than {@code 0},
628 * if {@code index + length} is greater than
629 * {@code this.capacity}, or
630 * if {@code dstIndex + length} is greater than
631 * {@code dst.capacity}
632 */
633 void getBytes(int index, ChannelBuffer dst, int dstIndex, int length);
634
635 /**
636 * Transfers this buffer's data to the specified destination starting at
637 * the specified absolute {@code index}.
638 * This method does not modify {@code readerIndex} or {@code writerIndex} of
639 * this buffer
640 *
641 * @throws IndexOutOfBoundsException
642 * if the specified {@code index} is less than {@code 0} or
643 * if {@code index + dst.length} is greater than
644 * {@code this.capacity}
645 */
646 void getBytes(int index, byte[] dst);
647
648 /**
649 * Transfers this buffer's data to the specified destination starting at
650 * the specified absolute {@code index}.
651 * This method does not modify {@code readerIndex} or {@code writerIndex}
652 * of this buffer.
653 *
654 * @param dstIndex the first index of the destination
655 * @param length the number of bytes to transfer
656 *
657 * @throws IndexOutOfBoundsException
658 * if the specified {@code index} is less than {@code 0},
659 * if the specified {@code dstIndex} is less than {@code 0},
660 * if {@code index + length} is greater than
661 * {@code this.capacity}, or
662 * if {@code dstIndex + length} is greater than
663 * {@code dst.length}
664 */
665 void getBytes(int index, byte[] dst, int dstIndex, int length);
666
667 /**
668 * Transfers this buffer's data to the specified destination starting at
669 * the specified absolute {@code index} until the destination's position
670 * reaches its limit.
671 * This method does not modify {@code readerIndex} or {@code writerIndex} of
672 * this buffer while the destination's {@code position} will be increased.
673 *
674 * @throws IndexOutOfBoundsException
675 * if the specified {@code index} is less than {@code 0} or
676 * if {@code index + dst.remaining()} is greater than
677 * {@code this.capacity}
678 */
679 void getBytes(int index, ByteBuffer dst);
680
681 /**
682 * Transfers this buffer's data to the specified stream starting at the
683 * specified absolute {@code index}.
684 * This method does not modify {@code readerIndex} or {@code writerIndex} of
685 * this buffer.
686 *
687 * @param length the number of bytes to transfer
688 *
689 * @throws IndexOutOfBoundsException
690 * if the specified {@code index} is less than {@code 0} or
691 * if {@code index + length} is greater than
692 * {@code this.capacity}
693 * @throws IOException
694 * if the specified stream threw an exception during I/O
695 */
696 void getBytes(int index, OutputStream out, int length) throws IOException;
697
698 /**
699 * Transfers this buffer's data to the specified channel starting at the
700 * specified absolute {@code index}.
701 * This method does not modify {@code readerIndex} or {@code writerIndex} of
702 * this buffer.
703 *
704 * @param length the maximum number of bytes to transfer
705 *
706 * @return the actual number of bytes written out to the specified channel
707 *
708 * @throws IndexOutOfBoundsException
709 * if the specified {@code index} is less than {@code 0} or
710 * if {@code index + length} is greater than
711 * {@code this.capacity}
712 * @throws IOException
713 * if the specified channel threw an exception during I/O
714 */
715 int getBytes(int index, GatheringByteChannel out, int length) throws IOException;
716
717 /**
718 * Sets the specified byte at the specified absolute {@code index} in this
719 * buffer. The 24 high-order bits of the specified value are ignored.
720 * This method does not modify {@code readerIndex} or {@code writerIndex} of
721 * this buffer.
722 *
723 * @throws IndexOutOfBoundsException
724 * if the specified {@code index} is less than {@code 0} or
725 * {@code index + 1} is greater than {@code this.capacity}
726 */
727 void setByte(int index, int value);
728
729 /**
730 * Sets the specified 16-bit short integer at the specified absolute
731 * {@code index} in this buffer. The 16 high-order bits of the specified
732 * value are ignored.
733 * This method does not modify {@code readerIndex} or {@code writerIndex} of
734 * this buffer.
735 *
736 * @throws IndexOutOfBoundsException
737 * if the specified {@code index} is less than {@code 0} or
738 * {@code index + 2} is greater than {@code this.capacity}
739 */
740 void setShort(int index, int value);
741
742 /**
743 * Sets the specified 24-bit medium integer at the specified absolute
744 * {@code index} in this buffer. Please note that the most significant
745 * byte is ignored in the specified value.
746 * This method does not modify {@code readerIndex} or {@code writerIndex} of
747 * this buffer.
748 *
749 * @throws IndexOutOfBoundsException
750 * if the specified {@code index} is less than {@code 0} or
751 * {@code index + 3} is greater than {@code this.capacity}
752 */
753 void setMedium(int index, int value);
754
755 /**
756 * Sets the specified 32-bit integer at the specified absolute
757 * {@code index} in this buffer.
758 * This method does not modify {@code readerIndex} or {@code writerIndex} of
759 * this buffer.
760 *
761 * @throws IndexOutOfBoundsException
762 * if the specified {@code index} is less than {@code 0} or
763 * {@code index + 4} is greater than {@code this.capacity}
764 */
765 void setInt(int index, int value);
766
767 /**
768 * Sets the specified 64-bit long integer at the specified absolute
769 * {@code index} in this buffer.
770 * This method does not modify {@code readerIndex} or {@code writerIndex} of
771 * this buffer.
772 *
773 * @throws IndexOutOfBoundsException
774 * if the specified {@code index} is less than {@code 0} or
775 * {@code index + 8} is greater than {@code this.capacity}
776 */
777 void setLong(int index, long value);
778
779 /**
780 * Sets the specified 2-byte UTF-16 character at the specified absolute
781 * {@code index} in this buffer.
782 * The 16 high-order bits of the specified value are ignored.
783 * This method does not modify {@code readerIndex} or {@code writerIndex} of
784 * this buffer.
785 *
786 * @throws IndexOutOfBoundsException
787 * if the specified {@code index} is less than {@code 0} or
788 * {@code index + 2} is greater than {@code this.capacity}
789 */
790 void setChar(int index, int value);
791
792 /**
793 * Sets the specified 32-bit floating-point number at the specified
794 * absolute {@code index} in this buffer.
795 * This method does not modify {@code readerIndex} or {@code writerIndex} of
796 * this buffer.
797 *
798 * @throws IndexOutOfBoundsException
799 * if the specified {@code index} is less than {@code 0} or
800 * {@code index + 4} is greater than {@code this.capacity}
801 */
802 void setFloat(int index, float value);
803
804 /**
805 * Sets the specified 64-bit floating-point number at the specified
806 * absolute {@code index} in this buffer.
807 * This method does not modify {@code readerIndex} or {@code writerIndex} of
808 * this buffer.
809 *
810 * @throws IndexOutOfBoundsException
811 * if the specified {@code index} is less than {@code 0} or
812 * {@code index + 8} is greater than {@code this.capacity}
813 */
814 void setDouble(int index, double value);
815
816 /**
817 * Transfers the specified source buffer's data to this buffer starting at
818 * the specified absolute {@code index} until the source buffer becomes
819 * unreadable. This method is basically same with
820 * {@link #setBytes(int, ChannelBuffer, int, int)}, except that this
821 * method increases the {@code readerIndex} of the source buffer by
822 * the number of the transferred bytes while
823 * {@link #setBytes(int, ChannelBuffer, int, int)} does not.
824 * This method does not modify {@code readerIndex} or {@code writerIndex} of
825 * the source buffer (i.e. {@code this}).
826 *
827 * @throws IndexOutOfBoundsException
828 * if the specified {@code index} is less than {@code 0} or
829 * if {@code index + src.readableBytes} is greater than
830 * {@code this.capacity}
831 */
832 void setBytes(int index, ChannelBuffer src);
833
834 /**
835 * Transfers the specified source buffer's data to this buffer starting at
836 * the specified absolute {@code index}. This method is basically same
837 * with {@link #setBytes(int, ChannelBuffer, int, int)}, except that this
838 * method increases the {@code readerIndex} of the source buffer by
839 * the number of the transferred bytes while
840 * {@link #setBytes(int, ChannelBuffer, int, int)} does not.
841 * This method does not modify {@code readerIndex} or {@code writerIndex} of
842 * the source buffer (i.e. {@code this}).
843 *
844 * @param length the number of bytes to transfer
845 *
846 * @throws IndexOutOfBoundsException
847 * if the specified {@code index} is less than {@code 0},
848 * if {@code index + length} is greater than
849 * {@code this.capacity}, or
850 * if {@code length} is greater than {@code src.readableBytes}
851 */
852 void setBytes(int index, ChannelBuffer src, int length);
853
854 /**
855 * Transfers the specified source buffer's data to this buffer starting at
856 * the specified absolute {@code index}.
857 * This method does not modify {@code readerIndex} or {@code writerIndex}
858 * of both the source (i.e. {@code this}) and the destination.
859 *
860 * @param srcIndex the first index of the source
861 * @param length the number of bytes to transfer
862 *
863 * @throws IndexOutOfBoundsException
864 * if the specified {@code index} is less than {@code 0},
865 * if the specified {@code srcIndex} is less than {@code 0},
866 * if {@code index + length} is greater than
867 * {@code this.capacity}, or
868 * if {@code srcIndex + length} is greater than
869 * {@code src.capacity}
870 */
871 void setBytes(int index, ChannelBuffer src, int srcIndex, int length);
872
873 /**
874 * Transfers the specified source array's data to this buffer starting at
875 * the specified absolute {@code index}.
876 * This method does not modify {@code readerIndex} or {@code writerIndex} of
877 * this buffer.
878 *
879 * @throws IndexOutOfBoundsException
880 * if the specified {@code index} is less than {@code 0} or
881 * if {@code index + src.length} is greater than
882 * {@code this.capacity}
883 */
884 void setBytes(int index, byte[] src);
885
886 /**
887 * Transfers the specified source array's data to this buffer starting at
888 * the specified absolute {@code index}.
889 * This method does not modify {@code readerIndex} or {@code writerIndex} of
890 * this buffer.
891 *
892 * @throws IndexOutOfBoundsException
893 * if the specified {@code index} is less than {@code 0},
894 * if the specified {@code srcIndex} is less than {@code 0},
895 * if {@code index + length} is greater than
896 * {@code this.capacity}, or
897 * if {@code srcIndex + length} is greater than {@code src.length}
898 */
899 void setBytes(int index, byte[] src, int srcIndex, int length);
900
901 /**
902 * Transfers the specified source buffer's data to this buffer starting at
903 * the specified absolute {@code index} until the source buffer's position
904 * reaches its limit.
905 * This method does not modify {@code readerIndex} or {@code writerIndex} of
906 * this buffer.
907 *
908 * @throws IndexOutOfBoundsException
909 * if the specified {@code index} is less than {@code 0} or
910 * if {@code index + src.remaining()} is greater than
911 * {@code this.capacity}
912 */
913 void setBytes(int index, ByteBuffer src);
914
915 /**
916 * Transfers the content of the specified source stream to this buffer
917 * starting at the specified absolute {@code index}.
918 * This method does not modify {@code readerIndex} or {@code writerIndex} of
919 * this buffer.
920 *
921 * @param length the number of bytes to transfer
922 *
923 * @return the actual number of bytes read in from the specified channel.
924 * {@code -1} if the specified channel is closed.
925 *
926 * @throws IndexOutOfBoundsException
927 * if the specified {@code index} is less than {@code 0} or
928 * if {@code index + length} is greater than {@code this.capacity}
929 * @throws IOException
930 * if the specified stream threw an exception during I/O
931 */
932 int setBytes(int index, InputStream in, int length) throws IOException;
933
934 /**
935 * Transfers the content of the specified source channel to this buffer
936 * starting at the specified absolute {@code index}.
937 * This method does not modify {@code readerIndex} or {@code writerIndex} of
938 * this buffer.
939 *
940 * @param length the maximum number of bytes to transfer
941 *
942 * @return the actual number of bytes read in from the specified channel.
943 * {@code -1} if the specified channel is closed.
944 *
945 * @throws IndexOutOfBoundsException
946 * if the specified {@code index} is less than {@code 0} or
947 * if {@code index + length} is greater than {@code this.capacity}
948 * @throws IOException
949 * if the specified channel threw an exception during I/O
950 */
951 int setBytes(int index, ScatteringByteChannel in, int length) throws IOException;
952
953 /**
954 * Fills this buffer with <tt>NUL (0x00)</tt> starting at the specified
955 * absolute {@code index}.
956 * This method does not modify {@code readerIndex} or {@code writerIndex} of
957 * this buffer.
958 *
959 * @param length the number of <tt>NUL</tt>s to write to the buffer
960 *
961 * @throws IndexOutOfBoundsException
962 * if the specified {@code index} is less than {@code 0} or
963 * if {@code index + length} is greater than {@code this.capacity}
964 */
965 void setZero(int index, int length);
966
967 /**
968 * Gets a byte at the current {@code readerIndex} and increases
969 * the {@code readerIndex} by {@code 1} in this buffer.
970 *
971 * @throws IndexOutOfBoundsException
972 * if {@code this.readableBytes} is less than {@code 1}
973 */
974 byte readByte();
975
976 /**
977 * Gets an unsigned byte at the current {@code readerIndex} and increases
978 * the {@code readerIndex} by {@code 1} in this buffer.
979 *
980 * @throws IndexOutOfBoundsException
981 * if {@code this.readableBytes} is less than {@code 1}
982 */
983 short readUnsignedByte();
984
985 /**
986 * Gets a 16-bit short integer at the current {@code readerIndex}
987 * and increases the {@code readerIndex} by {@code 2} in this buffer.
988 *
989 * @throws IndexOutOfBoundsException
990 * if {@code this.readableBytes} is less than {@code 2}
991 */
992 short readShort();
993
994 /**
995 * Gets an unsigned 16-bit short integer at the current {@code readerIndex}
996 * and increases the {@code readerIndex} by {@code 2} in this buffer.
997 *
998 * @throws IndexOutOfBoundsException
999 * if {@code this.readableBytes} is less than {@code 2}
1000 */
1001 int readUnsignedShort();
1002
1003 /**
1004 * Gets a 24-bit medium integer at the current {@code readerIndex}
1005 * and increases the {@code readerIndex} by {@code 3} in this buffer.
1006 *
1007 * @throws IndexOutOfBoundsException
1008 * if {@code this.readableBytes} is less than {@code 3}
1009 */
1010 int readMedium();
1011
1012 /**
1013 * Gets an unsigned 24-bit medium integer at the current {@code readerIndex}
1014 * and increases the {@code readerIndex} by {@code 3} in this buffer.
1015 *
1016 * @throws IndexOutOfBoundsException
1017 * if {@code this.readableBytes} is less than {@code 3}
1018 */
1019 int readUnsignedMedium();
1020
1021 /**
1022 * Gets a 32-bit integer at the current {@code readerIndex}
1023 * and increases the {@code readerIndex} by {@code 4} in this buffer.
1024 *
1025 * @throws IndexOutOfBoundsException
1026 * if {@code this.readableBytes} is less than {@code 4}
1027 */
1028 int readInt();
1029
1030 /**
1031 * Gets an unsigned 32-bit integer at the current {@code readerIndex}
1032 * and increases the {@code readerIndex} by {@code 4} in this buffer.
1033 *
1034 * @throws IndexOutOfBoundsException
1035 * if {@code this.readableBytes} is less than {@code 4}
1036 */
1037 long readUnsignedInt();
1038
1039 /**
1040 * Gets a 64-bit integer at the current {@code readerIndex}
1041 * and increases the {@code readerIndex} by {@code 8} in this buffer.
1042 *
1043 * @throws IndexOutOfBoundsException
1044 * if {@code this.readableBytes} is less than {@code 8}
1045 */
1046 long readLong();
1047
1048 /**
1049 * Gets a 2-byte UTF-16 character at the current {@code readerIndex}
1050 * and increases the {@code readerIndex} by {@code 2} in this buffer.
1051 *
1052 * @throws IndexOutOfBoundsException
1053 * if {@code this.readableBytes} is less than {@code 2}
1054 */
1055 char readChar();
1056
1057 /**
1058 * Gets a 32-bit floating point number at the current {@code readerIndex}
1059 * and increases the {@code readerIndex} by {@code 4} in this buffer.
1060 *
1061 * @throws IndexOutOfBoundsException
1062 * if {@code this.readableBytes} is less than {@code 4}
1063 */
1064 float readFloat();
1065
1066 /**
1067 * Gets a 64-bit floating point number at the current {@code readerIndex}
1068 * and increases the {@code readerIndex} by {@code 8} in this buffer.
1069 *
1070 * @throws IndexOutOfBoundsException
1071 * if {@code this.readableBytes} is less than {@code 8}
1072 */
1073 double readDouble();
1074
1075 /**
1076 * Transfers this buffer's data to a newly created buffer starting at
1077 * the current {@code readerIndex} and increases the {@code readerIndex}
1078 * by the number of the transferred bytes (= {@code length}).
1079 * The returned buffer's {@code readerIndex} and {@code writerIndex} are
1080 * {@code 0} and {@code length} respectively.
1081 *
1082 * @param length the number of bytes to transfer
1083 *
1084 * @return the newly created buffer which contains the transferred bytes
1085 *
1086 * @throws IndexOutOfBoundsException
1087 * if {@code length} is greater than {@code this.readableBytes}
1088 */
1089 ChannelBuffer readBytes(int length);
1090
1091 /**
1092 * Returns a new slice of this buffer's sub-region starting at the current
1093 * {@code readerIndex} and increases the {@code readerIndex} by the size
1094 * of the new slice (= {@code length}).
1095 *
1096 * @param length the size of the new slice
1097 *
1098 * @return the newly created slice
1099 *
1100 * @throws IndexOutOfBoundsException
1101 * if {@code length} is greater than {@code this.readableBytes}
1102 */
1103 ChannelBuffer readSlice(int length);
1104
1105 /**
1106 * Transfers this buffer's data to the specified destination starting at
1107 * the current {@code readerIndex} until the destination becomes
1108 * non-writable, and increases the {@code readerIndex} by the number of the
1109 * transferred bytes. This method is basically same with
1110 * {@link #readBytes(ChannelBuffer, int, int)}, except that this method
1111 * increases the {@code writerIndex} of the destination by the number of
1112 * the transferred bytes while {@link #readBytes(ChannelBuffer, int, int)}
1113 * does not.
1114 *
1115 * @throws IndexOutOfBoundsException
1116 * if {@code dst.writableBytes} is greater than
1117 * {@code this.readableBytes}
1118 */
1119 void readBytes(ChannelBuffer dst);
1120
1121 /**
1122 * Transfers this buffer's data to the specified destination starting at
1123 * the current {@code readerIndex} and increases the {@code readerIndex}
1124 * by the number of the transferred bytes (= {@code length}). This method
1125 * is basically same with {@link #readBytes(ChannelBuffer, int, int)},
1126 * except that this method increases the {@code writerIndex} of the
1127 * destination by the number of the transferred bytes (= {@code length})
1128 * while {@link #readBytes(ChannelBuffer, int, int)} does not.
1129 *
1130 * @throws IndexOutOfBoundsException
1131 * if {@code length} is greater than {@code this.readableBytes} or
1132 * if {@code length} is greater than {@code dst.writableBytes}
1133 */
1134 void readBytes(ChannelBuffer dst, int length);
1135
1136 /**
1137 * Transfers this buffer's data to the specified destination starting at
1138 * the current {@code readerIndex} and increases the {@code readerIndex}
1139 * by the number of the transferred bytes (= {@code length}).
1140 *
1141 * @param dstIndex the first index of the destination
1142 * @param length the number of bytes to transfer
1143 *
1144 * @throws IndexOutOfBoundsException
1145 * if the specified {@code dstIndex} is less than {@code 0},
1146 * if {@code length} is greater than {@code this.readableBytes}, or
1147 * if {@code dstIndex + length} is greater than
1148 * {@code dst.capacity}
1149 */
1150 void readBytes(ChannelBuffer dst, int dstIndex, int length);
1151
1152 /**
1153 * Transfers this buffer's data to the specified destination starting at
1154 * the current {@code readerIndex} and increases the {@code readerIndex}
1155 * by the number of the transferred bytes (= {@code dst.length}).
1156 *
1157 * @throws IndexOutOfBoundsException
1158 * if {@code dst.length} is greater than {@code this.readableBytes}
1159 */
1160 void readBytes(byte[] dst);
1161
1162 /**
1163 * Transfers this buffer's data to the specified destination starting at
1164 * the current {@code readerIndex} and increases the {@code readerIndex}
1165 * by the number of the transferred bytes (= {@code length}).
1166 *
1167 * @param dstIndex the first index of the destination
1168 * @param length the number of bytes to transfer
1169 *
1170 * @throws IndexOutOfBoundsException
1171 * if the specified {@code dstIndex} is less than {@code 0},
1172 * if {@code length} is greater than {@code this.readableBytes}, or
1173 * if {@code dstIndex + length} is greater than {@code dst.length}
1174 */
1175 void readBytes(byte[] dst, int dstIndex, int length);
1176
1177 /**
1178 * Transfers this buffer's data to the specified destination starting at
1179 * the current {@code readerIndex} until the destination's position
1180 * reaches its limit, and increases the {@code readerIndex} by the
1181 * number of the transferred bytes.
1182 *
1183 * @throws IndexOutOfBoundsException
1184 * if {@code dst.remaining()} is greater than
1185 * {@code this.readableBytes}
1186 */
1187 void readBytes(ByteBuffer dst);
1188
1189 /**
1190 * Transfers this buffer's data to the specified stream starting at the
1191 * current {@code readerIndex}.
1192 *
1193 * @param length the number of bytes to transfer
1194 *
1195 * @throws IndexOutOfBoundsException
1196 * if {@code length} is greater than {@code this.readableBytes}
1197 * @throws IOException
1198 * if the specified stream threw an exception during I/O
1199 */
1200 void readBytes(OutputStream out, int length) throws IOException;
1201
1202 /**
1203 * Transfers this buffer's data to the specified stream starting at the
1204 * current {@code readerIndex}.
1205 *
1206 * @param length the maximum number of bytes to transfer
1207 *
1208 * @return the actual number of bytes written out to the specified channel
1209 *
1210 * @throws IndexOutOfBoundsException
1211 * if {@code length} is greater than {@code this.readableBytes}
1212 * @throws IOException
1213 * if the specified channel threw an exception during I/O
1214 */
1215 int readBytes(GatheringByteChannel out, int length) throws IOException;
1216
1217 /**
1218 * Increases the current {@code readerIndex} by the specified
1219 * {@code length} in this buffer.
1220 *
1221 * @throws IndexOutOfBoundsException
1222 * if {@code length} is greater than {@code this.readableBytes}
1223 */
1224 void skipBytes(int length);
1225
1226 /**
1227 * Sets the specified byte at the current {@code writerIndex}
1228 * and increases the {@code writerIndex} by {@code 1} in this buffer.
1229 * The 24 high-order bits of the specified value are ignored.
1230 *
1231 * @throws IndexOutOfBoundsException
1232 * if {@code this.writableBytes} is less than {@code 1}
1233 */
1234 void writeByte(int value);
1235
1236 /**
1237 * Sets the specified 16-bit short integer at the current
1238 * {@code writerIndex} and increases the {@code writerIndex} by {@code 2}
1239 * in this buffer. The 16 high-order bits of the specified value are ignored.
1240 *
1241 * @throws IndexOutOfBoundsException
1242 * if {@code this.writableBytes} is less than {@code 2}
1243 */
1244 void writeShort(int value);
1245
1246 /**
1247 * Sets the specified 24-bit medium integer at the current
1248 * {@code writerIndex} and increases the {@code writerIndex} by {@code 3}
1249 * in this buffer.
1250 *
1251 * @throws IndexOutOfBoundsException
1252 * if {@code this.writableBytes} is less than {@code 3}
1253 */
1254 void writeMedium(int value);
1255
1256 /**
1257 * Sets the specified 32-bit integer at the current {@code writerIndex}
1258 * and increases the {@code writerIndex} by {@code 4} in this buffer.
1259 *
1260 * @throws IndexOutOfBoundsException
1261 * if {@code this.writableBytes} is less than {@code 4}
1262 */
1263 void writeInt(int value);
1264
1265 /**
1266 * Sets the specified 64-bit long integer at the current
1267 * {@code writerIndex} and increases the {@code writerIndex} by {@code 8}
1268 * in this buffer.
1269 *
1270 * @throws IndexOutOfBoundsException
1271 * if {@code this.writableBytes} is less than {@code 8}
1272 */
1273 void writeLong(long value);
1274
1275 /**
1276 * Sets the specified 2-byte UTF-16 character at the current
1277 * {@code writerIndex} and increases the {@code writerIndex} by {@code 2}
1278 * in this buffer. The 16 high-order bits of the specified value are ignored.
1279 *
1280 * @throws IndexOutOfBoundsException
1281 * if {@code this.writableBytes} is less than {@code 2}
1282 */
1283 void writeChar(int value);
1284
1285 /**
1286 * Sets the specified 32-bit floating point number at the current
1287 * {@code writerIndex} and increases the {@code writerIndex} by {@code 4}
1288 * in this buffer.
1289 *
1290 * @throws IndexOutOfBoundsException
1291 * if {@code this.writableBytes} is less than {@code 4}
1292 */
1293 void writeFloat(float value);
1294
1295 /**
1296 * Sets the specified 64-bit floating point number at the current
1297 * {@code writerIndex} and increases the {@code writerIndex} by {@code 8}
1298 * in this buffer.
1299 *
1300 * @throws IndexOutOfBoundsException
1301 * if {@code this.writableBytes} is less than {@code 8}
1302 */
1303 void writeDouble(double value);
1304
1305 /**
1306 * Transfers the specified source buffer's data to this buffer starting at
1307 * the current {@code writerIndex} until the source buffer becomes
1308 * unreadable, and increases the {@code writerIndex} by the number of
1309 * the transferred bytes. This method is basically same with
1310 * {@link #writeBytes(ChannelBuffer, int, int)}, except that this method
1311 * increases the {@code readerIndex} of the source buffer by the number of
1312 * the transferred bytes while {@link #writeBytes(ChannelBuffer, int, int)}
1313 * does not.
1314 *
1315 * @throws IndexOutOfBoundsException
1316 * if {@code src.readableBytes} is greater than
1317 * {@code this.writableBytes}
1318 */
1319 void writeBytes(ChannelBuffer src);
1320
1321 /**
1322 * Transfers the specified source buffer's data to this buffer starting at
1323 * the current {@code writerIndex} and increases the {@code writerIndex}
1324 * by the number of the transferred bytes (= {@code length}). This method
1325 * is basically same with {@link #writeBytes(ChannelBuffer, int, int)},
1326 * except that this method increases the {@code readerIndex} of the source
1327 * buffer by the number of the transferred bytes (= {@code length}) while
1328 * {@link #writeBytes(ChannelBuffer, int, int)} does not.
1329 *
1330 * @param length the number of bytes to transfer
1331 *
1332 * @throws IndexOutOfBoundsException
1333 * if {@code length} is greater than {@code this.writableBytes} or
1334 * if {@code length} is greater then {@code src.readableBytes}
1335 */
1336 void writeBytes(ChannelBuffer src, int length);
1337
1338 /**
1339 * Transfers the specified source buffer's data to this buffer starting at
1340 * the current {@code writerIndex} and increases the {@code writerIndex}
1341 * by the number of the transferred bytes (= {@code length}).
1342 *
1343 * @param srcIndex the first index of the source
1344 * @param length the number of bytes to transfer
1345 *
1346 * @throws IndexOutOfBoundsException
1347 * if the specified {@code srcIndex} is less than {@code 0},
1348 * if {@code srcIndex + length} is greater than
1349 * {@code src.capacity}, or
1350 * if {@code length} is greater than {@code this.writableBytes}
1351 */
1352 void writeBytes(ChannelBuffer src, int srcIndex, int length);
1353
1354 /**
1355 * Transfers the specified source array's data to this buffer starting at
1356 * the current {@code writerIndex} and increases the {@code writerIndex}
1357 * by the number of the transferred bytes (= {@code src.length}).
1358 *
1359 * @throws IndexOutOfBoundsException
1360 * if {@code src.length} is greater than {@code this.writableBytes}
1361 */
1362 void writeBytes(byte[] src);
1363
1364 /**
1365 * Transfers the specified source array's data to this buffer starting at
1366 * the current {@code writerIndex} and increases the {@code writerIndex}
1367 * by the number of the transferred bytes (= {@code length}).
1368 *
1369 * @param srcIndex the first index of the source
1370 * @param length the number of bytes to transfer
1371 *
1372 * @throws IndexOutOfBoundsException
1373 * if the specified {@code srcIndex} is less than {@code 0},
1374 * if {@code srcIndex + length} is greater than
1375 * {@code src.length}, or
1376 * if {@code length} is greater than {@code this.writableBytes}
1377 */
1378 void writeBytes(byte[] src, int srcIndex, int length);
1379
1380 /**
1381 * Transfers the specified source buffer's data to this buffer starting at
1382 * the current {@code writerIndex} until the source buffer's position
1383 * reaches its limit, and increases the {@code writerIndex} by the
1384 * number of the transferred bytes.
1385 *
1386 * @throws IndexOutOfBoundsException
1387 * if {@code src.remaining()} is greater than
1388 * {@code this.writableBytes}
1389 */
1390 void writeBytes(ByteBuffer src);
1391
1392 /**
1393 * Transfers the content of the specified stream to this buffer
1394 * starting at the current {@code writerIndex} and increases the
1395 * {@code writerIndex} by the number of the transferred bytes.
1396 *
1397 * @param length the number of bytes to transfer
1398 *
1399 * @return the actual number of bytes read in from the specified stream
1400 *
1401 * @throws IndexOutOfBoundsException
1402 * if {@code length} is greater than {@code this.writableBytes}
1403 * @throws IOException
1404 * if the specified stream threw an exception during I/O
1405 */
1406 int writeBytes(InputStream in, int length) throws IOException;
1407
1408 /**
1409 * Transfers the content of the specified channel to this buffer
1410 * starting at the current {@code writerIndex} and increases the
1411 * {@code writerIndex} by the number of the transferred bytes.
1412 *
1413 * @param length the maximum number of bytes to transfer
1414 *
1415 * @return the actual number of bytes read in from the specified channel
1416 *
1417 * @throws IndexOutOfBoundsException
1418 * if {@code length} is greater than {@code this.writableBytes}
1419 * @throws IOException
1420 * if the specified channel threw an exception during I/O
1421 */
1422 int writeBytes(ScatteringByteChannel in, int length) throws IOException;
1423
1424 /**
1425 * Fills this buffer with <tt>NUL (0x00)</tt> starting at the current
1426 * {@code writerIndex} and increases the {@code writerIndex} by the
1427 * specified {@code length}.
1428 *
1429 * @param length the number of <tt>NUL</tt>s to write to the buffer
1430 *
1431 * @throws IndexOutOfBoundsException
1432 * if {@code length} is greater than {@code this.writableBytes}
1433 */
1434 void writeZero(int length);
1435
1436 /**
1437 * Locates the first occurrence of the specified {@code value} in this
1438 * buffer. The search takes place from the specified {@code fromIndex}
1439 * (inclusive) to the specified {@code toIndex} (exclusive).
1440 * <p>
1441 * If {@code fromIndex} is greater than {@code toIndex}, the search is
1442 * performed in a reversed order.
1443 * <p>
1444 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1445 * this buffer.
1446 *
1447 * @return the absolute index of the first occurrence if found.
1448 * {@code -1} otherwise.
1449 */
1450 int indexOf(int fromIndex, int toIndex, byte value);
1451
1452 /**
1453 * Locates the first place where the specified {@code indexFinder}
1454 * returns {@code true}. The search takes place from the specified
1455 * {@code fromIndex} (inclusive) to the specified {@code toIndex}
1456 * (exclusive).
1457 * <p>
1458 * If {@code fromIndex} is greater than {@code toIndex}, the search is
1459 * performed in a reversed order.
1460 * <p>
1461 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1462 * this buffer.
1463 *
1464 * @return the absolute index where the specified {@code indexFinder}
1465 * returned {@code true}. {@code -1} if the {@code indexFinder}
1466 * did not return {@code true} at all.
1467 */
1468 int indexOf(int fromIndex, int toIndex, ChannelBufferIndexFinder indexFinder);
1469
1470 /**
1471 * Locates the first occurrence of the specified {@code value} in this
1472 * buffer. The search takes place from the current {@code readerIndex}
1473 * (inclusive) to the current {@code writerIndex} (exclusive).
1474 * <p>
1475 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1476 * this buffer.
1477 *
1478 * @return the number of bytes between the current {@code readerIndex}
1479 * and the first occurrence if found. {@code -1} otherwise.
1480 */
1481 int bytesBefore(byte value);
1482
1483 /**
1484 * Locates the first place where the specified {@code indexFinder} returns
1485 * {@code true}. The search takes place from the current {@code readerIndex}
1486 * (inclusive) to the current {@code writerIndex}.
1487 * <p>
1488 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1489 * this buffer.
1490 *
1491 * @return the number of bytes between the current {@code readerIndex}
1492 * and the first place where the {@code indexFinder} returned
1493 * {@code true}. {@code -1} if the {@code indexFinder} did not
1494 * return {@code true} at all.
1495 */
1496 int bytesBefore(ChannelBufferIndexFinder indexFinder);
1497
1498 /**
1499 * Locates the first occurrence of the specified {@code value} in this
1500 * buffer. The search starts from the current {@code readerIndex}
1501 * (inclusive) and lasts for the specified {@code length}.
1502 * <p>
1503 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1504 * this buffer.
1505 *
1506 * @return the number of bytes between the current {@code readerIndex}
1507 * and the first occurrence if found. {@code -1} otherwise.
1508 *
1509 * @throws IndexOutOfBoundsException
1510 * if {@code length} is greater than {@code this.readableBytes}
1511 */
1512 int bytesBefore(int length, byte value);
1513
1514 /**
1515 * Locates the first place where the specified {@code indexFinder} returns
1516 * {@code true}. The search starts the current {@code readerIndex}
1517 * (inclusive) and lasts for the specified {@code length}.
1518 * <p>
1519 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1520 * this buffer.
1521 *
1522 * @return the number of bytes between the current {@code readerIndex}
1523 * and the first place where the {@code indexFinder} returned
1524 * {@code true}. {@code -1} if the {@code indexFinder} did not
1525 * return {@code true} at all.
1526 *
1527 * @throws IndexOutOfBoundsException
1528 * if {@code length} is greater than {@code this.readableBytes}
1529 */
1530 int bytesBefore(int length, ChannelBufferIndexFinder indexFinder);
1531
1532 /**
1533 * Locates the first occurrence of the specified {@code value} in this
1534 * buffer. The search starts from the specified {@code index} (inclusive)
1535 * and lasts for the specified {@code length}.
1536 * <p>
1537 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1538 * this buffer.
1539 *
1540 * @return the number of bytes between the specified {@code index}
1541 * and the first occurrence if found. {@code -1} otherwise.
1542 *
1543 * @throws IndexOutOfBoundsException
1544 * if {@code index + length} is greater than {@code this.capacity}
1545 */
1546 int bytesBefore(int index, int length, byte value);
1547
1548 /**
1549 * Locates the first place where the specified {@code indexFinder} returns
1550 * {@code true}. The search starts the specified {@code index} (inclusive)
1551 * and lasts for the specified {@code length}.
1552 * <p>
1553 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1554 * this buffer.
1555 *
1556 * @return the number of bytes between the specified {@code index}
1557 * and the first place where the {@code indexFinder} returned
1558 * {@code true}. {@code -1} if the {@code indexFinder} did not
1559 * return {@code true} at all.
1560 *
1561 * @throws IndexOutOfBoundsException
1562 * if {@code index + length} is greater than {@code this.capacity}
1563 */
1564 int bytesBefore(int index, int length, ChannelBufferIndexFinder indexFinder);
1565
1566 /**
1567 * Returns a copy of this buffer's readable bytes. Modifying the content
1568 * of the returned buffer or this buffer does not affect each other at all.
1569 * This method is identical to {@code buf.copy(buf.readerIndex(), buf.readableBytes())}.
1570 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1571 * this buffer.
1572 */
1573 ChannelBuffer copy();
1574
1575 /**
1576 * Returns a copy of this buffer's sub-region. Modifying the content of
1577 * the returned buffer or this buffer does not affect each other at all.
1578 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1579 * this buffer.
1580 */
1581 ChannelBuffer copy(int index, int length);
1582
1583 /**
1584 * Returns a slice of this buffer's readable bytes. Modifying the content
1585 * of the returned buffer or this buffer affects each other's content
1586 * while they maintain separate indexes and marks. This method is
1587 * identical to {@code buf.slice(buf.readerIndex(), buf.readableBytes())}.
1588 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1589 * this buffer.
1590 */
1591 ChannelBuffer slice();
1592
1593 /**
1594 * Returns a slice of this buffer's sub-region. Modifying the content of
1595 * the returned buffer or this buffer affects each other's content while
1596 * they maintain separate indexes and marks.
1597 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1598 * this buffer.
1599 */
1600 ChannelBuffer slice(int index, int length);
1601
1602 /**
1603 * Returns a buffer which shares the whole region of this buffer.
1604 * Modifying the content of the returned buffer or this buffer affects
1605 * each other's content while they maintain separate indexes and marks.
1606 * This method is identical to {@code buf.slice(0, buf.capacity())}.
1607 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1608 * this buffer.
1609 */
1610 ChannelBuffer duplicate();
1611
1612 /**
1613 * Converts this buffer's readable bytes into a NIO buffer. The returned
1614 * buffer might or might not share the content with this buffer, while
1615 * they have separate indexes and marks. This method is identical to
1616 * {@code buf.toByteBuffer(buf.readerIndex(), buf.readableBytes())}.
1617 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1618 * this buffer.
1619 */
1620 ByteBuffer toByteBuffer();
1621
1622 /**
1623 * Converts this buffer's sub-region into a NIO buffer. The returned
1624 * buffer might or might not share the content with this buffer, while
1625 * they have separate indexes and marks.
1626 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1627 * this buffer.
1628 */
1629 ByteBuffer toByteBuffer(int index, int length);
1630
1631 /**
1632 * Converts this buffer's readable bytes into an array of NIO buffers.
1633 * The returned buffers might or might not share the content with this
1634 * buffer, while they have separate indexes and marks. This method is
1635 * identical to {@code buf.toByteBuffers(buf.readerIndex(), buf.readableBytes())}.
1636 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1637 * this buffer.
1638 */
1639 ByteBuffer[] toByteBuffers();
1640
1641 /**
1642 * Converts this buffer's sub-region into an array of NIO buffers.
1643 * The returned buffers might or might not share the content with this
1644 * buffer, while they have separate indexes and marks.
1645 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1646 * this buffer.
1647 */
1648 ByteBuffer[] toByteBuffers(int index, int length);
1649
1650 /**
1651 * Returns {@code true} if and only if this buffer has a backing byte array.
1652 * If this method returns true, you can safely call {@link #array()} and
1653 * {@link #arrayOffset()}.
1654 */
1655 boolean hasArray();
1656
1657 /**
1658 * Returns the backing byte array of this buffer.
1659 *
1660 * @throws UnsupportedOperationException
1661 * if there no accessible backing byte array
1662 */
1663 byte[] array();
1664
1665 /**
1666 * Returns the offset of the first byte within the backing byte array of
1667 * this buffer.
1668 *
1669 * @throws UnsupportedOperationException
1670 * if there no accessible backing byte array
1671 */
1672 int arrayOffset();
1673
1674 /**
1675 * Decodes this buffer's readable bytes into a string with the specified
1676 * character set name. This method is identical to
1677 * {@code buf.toString(buf.readerIndex(), buf.readableBytes(), charsetName)}.
1678 * This method does not modify {@code readerIndex} or {@code writerIndex} of
1679 * this buffer.
1680 *
1681 * @throws UnsupportedCharsetException
1682 * if the specified character set name is not supported by the
1683 * current VM
1684 */
1685 String toString(Charset charset);
1686
1687 /**
1688 * Decodes this buffer's sub-region into a string with the specified
1689 * character set. This method does not modify {@code readerIndex} or
1690 * {@code writerIndex} of this buffer.
1691 */
1692 String toString(int index, int length, Charset charset);
1693
1694 /**
1695 * Returns a hash code which was calculated from the content of this
1696 * buffer. If there's a byte array which is
1697 * {@linkplain #equals(Object) equal to} this array, both arrays should
1698 * return the same value.
1699 */
1700 int hashCode();
1701
1702 /**
1703 * Determines if the content of the specified buffer is identical to the
1704 * content of this array. 'Identical' here means:
1705 * <ul>
1706 * <li>the size of the contents of the two buffers are same and</li>
1707 * <li>every single byte of the content of the two buffers are same.</li>
1708 * </ul>
1709 * Please note that it does not compare {@link #readerIndex()} nor
1710 * {@link #writerIndex()}. This method also returns {@code false} for
1711 * {@code null} and an object which is not an instance of
1712 * {@link ChannelBuffer} type.
1713 */
1714 boolean equals(Object obj);
1715
1716 /**
1717 * Compares the content of the specified buffer to the content of this
1718 * buffer. Comparison is performed in the same manner with the string
1719 * comparison functions of various languages such as {@code strcmp},
1720 * {@code memcmp} and {@link String#compareTo(String)}.
1721 */
1722 int compareTo(ChannelBuffer buffer);
1723
1724 /**
1725 * Returns the string representation of this buffer. This method does not
1726 * necessarily return the whole content of the buffer but returns
1727 * the values of the key properties such as {@link #readerIndex()},
1728 * {@link #writerIndex()} and {@link #capacity()}.
1729 */
1730 String toString();
1731 }
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