1 /*
2 * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import jdk.internal.math.DoubleToDecimal;
29 import jdk.internal.math.FloatToDecimal;
30
31 import java.io.IOException;
32 import java.util.Arrays;
33 import java.util.Spliterator;
34 import java.util.stream.IntStream;
35 import java.util.stream.StreamSupport;
36
37 import static java.lang.String.COMPACT_STRINGS;
38 import static java.lang.String.UTF16;
39 import static java.lang.String.LATIN1;
40 import static java.lang.String.checkIndex;
41 import static java.lang.String.checkOffset;
42
43 /**
44 * A mutable sequence of characters.
45 * <p>
46 * Implements a modifiable string. At any point in time it contains some
47 * particular sequence of characters, but the length and content of the
48 * sequence can be changed through certain method calls.
49 *
50 * <p>Unless otherwise noted, passing a {@code null} argument to a constructor
51 * or method in this class will cause a {@link NullPointerException} to be
52 * thrown.
53 *
54 * @author Michael McCloskey
55 * @author Martin Buchholz
56 * @author Ulf Zibis
57 * @since 1.5
58 */
59 abstract class AbstractStringBuilder implements Appendable, CharSequence {
60 /**
61 * The value is used for character storage.
62 */
63 byte[] value;
64
65 /**
66 * The id of the encoding used to encode the bytes in {@code value}.
67 */
68 byte coder;
69
70 /**
71 * The count is the number of characters used.
72 */
73 int count;
74
75 private static final byte[] EMPTYVALUE = new byte[0];
76
77 /**
78 * This no-arg constructor is necessary for serialization of subclasses.
79 */
80 AbstractStringBuilder() {
81 value = EMPTYVALUE;
82 }
83
84 /**
85 * Creates an AbstractStringBuilder of the specified capacity.
86 */
87 AbstractStringBuilder(int capacity) {
88 if (COMPACT_STRINGS) {
89 value = new byte[capacity];
90 coder = LATIN1;
91 } else {
92 value = StringUTF16.newBytesFor(capacity);
93 coder = UTF16;
94 }
95 }
96
97 /**
98 * Constructs an AbstractStringBuilder that contains the same characters
99 * as the specified {@code String}. The initial capacity of
100 * the string builder is {@code 16} plus the length of the
101 * {@code String} argument.
102 *
103 * @param str the string to copy.
104 */
105 AbstractStringBuilder(String str) {
106 int length = str.length();
107 int capacity = (length < Integer.MAX_VALUE - 16)
108 ? length + 16 : Integer.MAX_VALUE;
109 final byte initCoder = str.coder();
110 coder = initCoder;
111 value = (initCoder == LATIN1)
112 ? new byte[capacity] : StringUTF16.newBytesFor(capacity);
113 append(str);
114 }
115
116 /**
117 * Constructs an AbstractStringBuilder that contains the same characters
118 * as the specified {@code CharSequence}. The initial capacity of
119 * the string builder is {@code 16} plus the length of the
120 * {@code CharSequence} argument.
121 *
122 * @param seq the sequence to copy.
123 */
124 AbstractStringBuilder(CharSequence seq) {
125 int length = seq.length();
126 if (length < 0) {
127 throw new NegativeArraySizeException("Negative length: " + length);
128 }
129 int capacity = (length < Integer.MAX_VALUE - 16)
130 ? length + 16 : Integer.MAX_VALUE;
131
132 final byte initCoder;
133 if (COMPACT_STRINGS) {
134 if (seq instanceof AbstractStringBuilder) {
135 initCoder = ((AbstractStringBuilder)seq).getCoder();
136 } else if (seq instanceof String) {
137 initCoder = ((String)seq).coder();
138 } else {
139 initCoder = LATIN1;
140 }
141 } else {
142 initCoder = UTF16;
143 }
144
145 coder = initCoder;
146 value = (initCoder == LATIN1)
147 ? new byte[capacity] : StringUTF16.newBytesFor(capacity);
148 append(seq);
149 }
150
151 /**
152 * Compares the objects of two AbstractStringBuilder implementations lexicographically.
153 *
154 * @since 11
155 */
156 int compareTo(AbstractStringBuilder another) {
157 if (this == another) {
158 return 0;
159 }
160
161 byte val1[] = value;
162 byte val2[] = another.value;
163 int count1 = this.count;
164 int count2 = another.count;
165
166 if (coder == another.coder) {
167 return isLatin1() ? StringLatin1.compareTo(val1, val2, count1, count2)
168 : StringUTF16.compareTo(val1, val2, count1, count2);
169 }
170 return isLatin1() ? StringLatin1.compareToUTF16(val1, val2, count1, count2)
171 : StringUTF16.compareToLatin1(val1, val2, count1, count2);
172 }
173
174 /**
175 * Returns the length (character count).
176 *
177 * @return the length of the sequence of characters currently
178 * represented by this object
179 */
180 @Override
181 public int length() {
182 return count;
183 }
184
185 /**
186 * Returns the current capacity. The capacity is the amount of storage
187 * available for newly inserted characters, beyond which an allocation
188 * will occur.
189 *
190 * @return the current capacity
191 */
192 public int capacity() {
193 return value.length >> coder;
194 }
195
196 /**
197 * Ensures that the capacity is at least equal to the specified minimum.
198 * If the current capacity is less than the argument, then a new internal
199 * array is allocated with greater capacity. The new capacity is the
200 * larger of:
201 * <ul>
202 * <li>The {@code minimumCapacity} argument.
203 * <li>Twice the old capacity, plus {@code 2}.
204 * </ul>
205 * If the {@code minimumCapacity} argument is nonpositive, this
206 * method takes no action and simply returns.
207 * Note that subsequent operations on this object can reduce the
208 * actual capacity below that requested here.
209 *
210 * @param minimumCapacity the minimum desired capacity.
211 */
212 public void ensureCapacity(int minimumCapacity) {
213 if (minimumCapacity > 0) {
214 ensureCapacityInternal(minimumCapacity);
215 }
216 }
217
218 /**
219 * For positive values of {@code minimumCapacity}, this method
220 * behaves like {@code ensureCapacity}, however it is never
221 * synchronized.
222 * If {@code minimumCapacity} is non positive due to numeric
223 * overflow, this method throws {@code OutOfMemoryError}.
224 */
225 private void ensureCapacityInternal(int minimumCapacity) {
226 // overflow-conscious code
227 int oldCapacity = value.length >> coder;
228 if (minimumCapacity - oldCapacity > 0) {
229 value = Arrays.copyOf(value,
230 newCapacity(minimumCapacity) << coder);
231 }
232 }
233
234 /**
235 * The maximum size of array to allocate (unless necessary).
236 * Some VMs reserve some header words in an array.
237 * Attempts to allocate larger arrays may result in
238 * OutOfMemoryError: Requested array size exceeds VM limit
239 */
240 private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
241
242 /**
243 * Returns a capacity at least as large as the given minimum capacity.
244 * Returns the current capacity increased by the same amount + 2 if
245 * that suffices.
246 * Will not return a capacity greater than
247 * {@code (MAX_ARRAY_SIZE >> coder)} unless the given minimum capacity
248 * is greater than that.
249 *
250 * @param minCapacity the desired minimum capacity
251 * @throws OutOfMemoryError if minCapacity is less than zero or
252 * greater than (Integer.MAX_VALUE >> coder)
253 */
254 private int newCapacity(int minCapacity) {
255 // overflow-conscious code
256 int oldCapacity = value.length >> coder;
257 int newCapacity = (oldCapacity << 1) + 2;
258 if (newCapacity - minCapacity < 0) {
259 newCapacity = minCapacity;
260 }
261 int SAFE_BOUND = MAX_ARRAY_SIZE >> coder;
262 return (newCapacity <= 0 || SAFE_BOUND - newCapacity < 0)
263 ? hugeCapacity(minCapacity)
264 : newCapacity;
265 }
266
267 private int hugeCapacity(int minCapacity) {
268 int SAFE_BOUND = MAX_ARRAY_SIZE >> coder;
269 int UNSAFE_BOUND = Integer.MAX_VALUE >> coder;
270 if (UNSAFE_BOUND - minCapacity < 0) { // overflow
271 throw new OutOfMemoryError();
272 }
273 return (minCapacity > SAFE_BOUND)
274 ? minCapacity : SAFE_BOUND;
275 }
276
277 /**
278 * If the coder is "isLatin1", this inflates the internal 8-bit storage
279 * to 16-bit <hi=0, low> pair storage.
280 */
281 private void inflate() {
282 if (!isLatin1()) {
283 return;
284 }
285 byte[] buf = StringUTF16.newBytesFor(value.length);
286 StringLatin1.inflate(value, 0, buf, 0, count);
287 this.value = buf;
288 this.coder = UTF16;
289 }
290
291 /**
292 * Attempts to reduce storage used for the character sequence.
293 * If the buffer is larger than necessary to hold its current sequence of
294 * characters, then it may be resized to become more space efficient.
295 * Calling this method may, but is not required to, affect the value
296 * returned by a subsequent call to the {@link #capacity()} method.
297 */
298 public void trimToSize() {
299 int length = count << coder;
300 if (length < value.length) {
301 value = Arrays.copyOf(value, length);
302 }
303 }
304
305 /**
306 * Sets the length of the character sequence.
307 * The sequence is changed to a new character sequence
308 * whose length is specified by the argument. For every nonnegative
309 * index <i>k</i> less than {@code newLength}, the character at
310 * index <i>k</i> in the new character sequence is the same as the
311 * character at index <i>k</i> in the old sequence if <i>k</i> is less
312 * than the length of the old character sequence; otherwise, it is the
313 * null character {@code '\u005Cu0000'}.
314 *
315 * In other words, if the {@code newLength} argument is less than
316 * the current length, the length is changed to the specified length.
317 * <p>
318 * If the {@code newLength} argument is greater than or equal
319 * to the current length, sufficient null characters
320 * ({@code '\u005Cu0000'}) are appended so that
321 * length becomes the {@code newLength} argument.
322 * <p>
323 * The {@code newLength} argument must be greater than or equal
324 * to {@code 0}.
325 *
326 * @param newLength the new length
327 * @throws IndexOutOfBoundsException if the
328 * {@code newLength} argument is negative.
329 */
330 public void setLength(int newLength) {
331 if (newLength < 0) {
332 throw new StringIndexOutOfBoundsException(newLength);
333 }
334 ensureCapacityInternal(newLength);
335 if (count < newLength) {
336 if (isLatin1()) {
337 StringLatin1.fillNull(value, count, newLength);
338 } else {
339 StringUTF16.fillNull(value, count, newLength);
340 }
341 }
342 count = newLength;
343 }
344
345 /**
346 * Returns the {@code char} value in this sequence at the specified index.
347 * The first {@code char} value is at index {@code 0}, the next at index
348 * {@code 1}, and so on, as in array indexing.
349 * <p>
350 * The index argument must be greater than or equal to
351 * {@code 0}, and less than the length of this sequence.
352 *
353 * <p>If the {@code char} value specified by the index is a
354 * <a href="Character.html#unicode">surrogate</a>, the surrogate
355 * value is returned.
356 *
357 * @param index the index of the desired {@code char} value.
358 * @return the {@code char} value at the specified index.
359 * @throws IndexOutOfBoundsException if {@code index} is
360 * negative or greater than or equal to {@code length()}.
361 */
362 @Override
363 public char charAt(int index) {
364 checkIndex(index, count);
365 if (isLatin1()) {
366 return (char)(value[index] & 0xff);
367 }
368 return StringUTF16.charAt(value, index);
369 }
370
371 /**
372 * Returns the character (Unicode code point) at the specified
373 * index. The index refers to {@code char} values
374 * (Unicode code units) and ranges from {@code 0} to
375 * {@link #length()}{@code - 1}.
376 *
377 * <p> If the {@code char} value specified at the given index
378 * is in the high-surrogate range, the following index is less
379 * than the length of this sequence, and the
380 * {@code char} value at the following index is in the
381 * low-surrogate range, then the supplementary code point
382 * corresponding to this surrogate pair is returned. Otherwise,
383 * the {@code char} value at the given index is returned.
384 *
385 * @param index the index to the {@code char} values
386 * @return the code point value of the character at the
387 * {@code index}
388 * @throws IndexOutOfBoundsException if the {@code index}
389 * argument is negative or not less than the length of this
390 * sequence.
391 */
392 public int codePointAt(int index) {
393 int count = this.count;
394 byte[] value = this.value;
395 checkIndex(index, count);
396 if (isLatin1()) {
397 return value[index] & 0xff;
398 }
399 return StringUTF16.codePointAtSB(value, index, count);
400 }
401
402 /**
403 * Returns the character (Unicode code point) before the specified
404 * index. The index refers to {@code char} values
405 * (Unicode code units) and ranges from {@code 1} to {@link
406 * #length()}.
407 *
408 * <p> If the {@code char} value at {@code (index - 1)}
409 * is in the low-surrogate range, {@code (index - 2)} is not
410 * negative, and the {@code char} value at {@code (index -
411 * 2)} is in the high-surrogate range, then the
412 * supplementary code point value of the surrogate pair is
413 * returned. If the {@code char} value at {@code index -
414 * 1} is an unpaired low-surrogate or a high-surrogate, the
415 * surrogate value is returned.
416 *
417 * @param index the index following the code point that should be returned
418 * @return the Unicode code point value before the given index.
419 * @throws IndexOutOfBoundsException if the {@code index}
420 * argument is less than 1 or greater than the length
421 * of this sequence.
422 */
423 public int codePointBefore(int index) {
424 int i = index - 1;
425 if (i < 0 || i >= count) {
426 throw new StringIndexOutOfBoundsException(index);
427 }
428 if (isLatin1()) {
429 return value[i] & 0xff;
430 }
431 return StringUTF16.codePointBeforeSB(value, index);
432 }
433
434 /**
435 * Returns the number of Unicode code points in the specified text
436 * range of this sequence. The text range begins at the specified
437 * {@code beginIndex} and extends to the {@code char} at
438 * index {@code endIndex - 1}. Thus the length (in
439 * {@code char}s) of the text range is
440 * {@code endIndex-beginIndex}. Unpaired surrogates within
441 * this sequence count as one code point each.
442 *
443 * @param beginIndex the index to the first {@code char} of
444 * the text range.
445 * @param endIndex the index after the last {@code char} of
446 * the text range.
447 * @return the number of Unicode code points in the specified text
448 * range
449 * @throws IndexOutOfBoundsException if the
450 * {@code beginIndex} is negative, or {@code endIndex}
451 * is larger than the length of this sequence, or
452 * {@code beginIndex} is larger than {@code endIndex}.
453 */
454 public int codePointCount(int beginIndex, int endIndex) {
455 if (beginIndex < 0 || endIndex > count || beginIndex > endIndex) {
456 throw new IndexOutOfBoundsException();
457 }
458 if (isLatin1()) {
459 return endIndex - beginIndex;
460 }
461 return StringUTF16.codePointCountSB(value, beginIndex, endIndex);
462 }
463
464 /**
465 * Returns the index within this sequence that is offset from the
466 * given {@code index} by {@code codePointOffset} code
467 * points. Unpaired surrogates within the text range given by
468 * {@code index} and {@code codePointOffset} count as
469 * one code point each.
470 *
471 * @param index the index to be offset
472 * @param codePointOffset the offset in code points
473 * @return the index within this sequence
474 * @throws IndexOutOfBoundsException if {@code index}
475 * is negative or larger then the length of this sequence,
476 * or if {@code codePointOffset} is positive and the subsequence
477 * starting with {@code index} has fewer than
478 * {@code codePointOffset} code points,
479 * or if {@code codePointOffset} is negative and the subsequence
480 * before {@code index} has fewer than the absolute value of
481 * {@code codePointOffset} code points.
482 */
483 public int offsetByCodePoints(int index, int codePointOffset) {
484 if (index < 0 || index > count) {
485 throw new IndexOutOfBoundsException();
486 }
487 return Character.offsetByCodePoints(this,
488 index, codePointOffset);
489 }
490
491 /**
492 * Characters are copied from this sequence into the
493 * destination character array {@code dst}. The first character to
494 * be copied is at index {@code srcBegin}; the last character to
495 * be copied is at index {@code srcEnd-1}. The total number of
496 * characters to be copied is {@code srcEnd-srcBegin}. The
497 * characters are copied into the subarray of {@code dst} starting
498 * at index {@code dstBegin} and ending at index:
499 * <pre>{@code
500 * dstbegin + (srcEnd-srcBegin) - 1
501 * }</pre>
502 *
503 * @param srcBegin start copying at this offset.
504 * @param srcEnd stop copying at this offset.
505 * @param dst the array to copy the data into.
506 * @param dstBegin offset into {@code dst}.
507 * @throws IndexOutOfBoundsException if any of the following is true:
508 * <ul>
509 * <li>{@code srcBegin} is negative
510 * <li>{@code dstBegin} is negative
511 * <li>the {@code srcBegin} argument is greater than
512 * the {@code srcEnd} argument.
513 * <li>{@code srcEnd} is greater than
514 * {@code this.length()}.
515 * <li>{@code dstBegin+srcEnd-srcBegin} is greater than
516 * {@code dst.length}
517 * </ul>
518 */
519 public void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)
520 {
521 checkRangeSIOOBE(srcBegin, srcEnd, count); // compatible to old version
522 int n = srcEnd - srcBegin;
523 checkRange(dstBegin, dstBegin + n, dst.length);
524 if (isLatin1()) {
525 StringLatin1.getChars(value, srcBegin, srcEnd, dst, dstBegin);
526 } else {
527 StringUTF16.getChars(value, srcBegin, srcEnd, dst, dstBegin);
528 }
529 }
530
531 /**
532 * The character at the specified index is set to {@code ch}. This
533 * sequence is altered to represent a new character sequence that is
534 * identical to the old character sequence, except that it contains the
535 * character {@code ch} at position {@code index}.
536 * <p>
537 * The index argument must be greater than or equal to
538 * {@code 0}, and less than the length of this sequence.
539 *
540 * @param index the index of the character to modify.
541 * @param ch the new character.
542 * @throws IndexOutOfBoundsException if {@code index} is
543 * negative or greater than or equal to {@code length()}.
544 */
545 public void setCharAt(int index, char ch) {
546 checkIndex(index, count);
547 if (isLatin1() && StringLatin1.canEncode(ch)) {
548 value[index] = (byte)ch;
549 } else {
550 if (isLatin1()) {
551 inflate();
552 }
553 StringUTF16.putCharSB(value, index, ch);
554 }
555 }
556
557 /**
558 * Appends the string representation of the {@code Object} argument.
559 * <p>
560 * The overall effect is exactly as if the argument were converted
561 * to a string by the method {@link String#valueOf(Object)},
562 * and the characters of that string were then
563 * {@link #append(String) appended} to this character sequence.
564 *
565 * @param obj an {@code Object}.
566 * @return a reference to this object.
567 */
568 public AbstractStringBuilder append(Object obj) {
569 return append(String.valueOf(obj));
570 }
571
572 /**
573 * Appends the specified string to this character sequence.
574 * <p>
575 * The characters of the {@code String} argument are appended, in
576 * order, increasing the length of this sequence by the length of the
577 * argument. If {@code str} is {@code null}, then the four
578 * characters {@code "null"} are appended.
579 * <p>
580 * Let <i>n</i> be the length of this character sequence just prior to
581 * execution of the {@code append} method. Then the character at
582 * index <i>k</i> in the new character sequence is equal to the character
583 * at index <i>k</i> in the old character sequence, if <i>k</i> is less
584 * than <i>n</i>; otherwise, it is equal to the character at index
585 * <i>k-n</i> in the argument {@code str}.
586 *
587 * @param str a string.
588 * @return a reference to this object.
589 */
590 public AbstractStringBuilder append(String str) {
591 if (str == null) {
592 return appendNull();
593 }
594 int len = str.length();
595 ensureCapacityInternal(count + len);
596 putStringAt(count, str);
597 count += len;
598 return this;
599 }
600
601 // Documentation in subclasses because of synchro difference
602 public AbstractStringBuilder append(StringBuffer sb) {
603 return this.append((AbstractStringBuilder)sb);
604 }
605
606 /**
607 * @since 1.8
608 */
609 AbstractStringBuilder append(AbstractStringBuilder asb) {
610 if (asb == null) {
611 return appendNull();
612 }
613 int len = asb.length();
614 ensureCapacityInternal(count + len);
615 if (getCoder() != asb.getCoder()) {
616 inflate();
617 }
618 asb.getBytes(value, count, coder);
619 count += len;
620 return this;
621 }
622
623 // Documentation in subclasses because of synchro difference
624 @Override
625 public AbstractStringBuilder append(CharSequence s) {
626 if (s == null) {
627 return appendNull();
628 }
629 if (s instanceof String) {
630 return this.append((String)s);
631 }
632 if (s instanceof AbstractStringBuilder) {
633 return this.append((AbstractStringBuilder)s);
634 }
635 return this.append(s, 0, s.length());
636 }
637
638 private AbstractStringBuilder appendNull() {
639 ensureCapacityInternal(count + 4);
640 int count = this.count;
641 byte[] val = this.value;
642 if (isLatin1()) {
643 val[count++] = 'n';
644 val[count++] = 'u';
645 val[count++] = 'l';
646 val[count++] = 'l';
647 } else {
648 count = StringUTF16.putCharsAt(val, count, 'n', 'u', 'l', 'l');
649 }
650 this.count = count;
651 return this;
652 }
653
654 /**
655 * Appends a subsequence of the specified {@code CharSequence} to this
656 * sequence.
657 * <p>
658 * Characters of the argument {@code s}, starting at
659 * index {@code start}, are appended, in order, to the contents of
660 * this sequence up to the (exclusive) index {@code end}. The length
661 * of this sequence is increased by the value of {@code end - start}.
662 * <p>
663 * Let <i>n</i> be the length of this character sequence just prior to
664 * execution of the {@code append} method. Then the character at
665 * index <i>k</i> in this character sequence becomes equal to the
666 * character at index <i>k</i> in this sequence, if <i>k</i> is less than
667 * <i>n</i>; otherwise, it is equal to the character at index
668 * <i>k+start-n</i> in the argument {@code s}.
669 * <p>
670 * If {@code s} is {@code null}, then this method appends
671 * characters as if the s parameter was a sequence containing the four
672 * characters {@code "null"}.
673 *
674 * @param s the sequence to append.
675 * @param start the starting index of the subsequence to be appended.
676 * @param end the end index of the subsequence to be appended.
677 * @return a reference to this object.
678 * @throws IndexOutOfBoundsException if
679 * {@code start} is negative, or
680 * {@code start} is greater than {@code end} or
681 * {@code end} is greater than {@code s.length()}
682 */
683 @Override
684 public AbstractStringBuilder append(CharSequence s, int start, int end) {
685 if (s == null) {
686 s = "null";
687 }
688 checkRange(start, end, s.length());
689 int len = end - start;
690 ensureCapacityInternal(count + len);
691 appendChars(s, start, end);
692 return this;
693 }
694
695 /**
696 * Appends the string representation of the {@code char} array
697 * argument to this sequence.
698 * <p>
699 * The characters of the array argument are appended, in order, to
700 * the contents of this sequence. The length of this sequence
701 * increases by the length of the argument.
702 * <p>
703 * The overall effect is exactly as if the argument were converted
704 * to a string by the method {@link String#valueOf(char[])},
705 * and the characters of that string were then
706 * {@link #append(String) appended} to this character sequence.
707 *
708 * @param str the characters to be appended.
709 * @return a reference to this object.
710 */
711 public AbstractStringBuilder append(char[] str) {
712 int len = str.length;
713 ensureCapacityInternal(count + len);
714 appendChars(str, 0, len);
715 return this;
716 }
717
718 /**
719 * Appends the string representation of a subarray of the
720 * {@code char} array argument to this sequence.
721 * <p>
722 * Characters of the {@code char} array {@code str}, starting at
723 * index {@code offset}, are appended, in order, to the contents
724 * of this sequence. The length of this sequence increases
725 * by the value of {@code len}.
726 * <p>
727 * The overall effect is exactly as if the arguments were converted
728 * to a string by the method {@link String#valueOf(char[],int,int)},
729 * and the characters of that string were then
730 * {@link #append(String) appended} to this character sequence.
731 *
732 * @param str the characters to be appended.
733 * @param offset the index of the first {@code char} to append.
734 * @param len the number of {@code char}s to append.
735 * @return a reference to this object.
736 * @throws IndexOutOfBoundsException
737 * if {@code offset < 0} or {@code len < 0}
738 * or {@code offset+len > str.length}
739 */
740 public AbstractStringBuilder append(char str[], int offset, int len) {
741 int end = offset + len;
742 checkRange(offset, end, str.length);
743 ensureCapacityInternal(count + len);
744 appendChars(str, offset, end);
745 return this;
746 }
747
748 /**
749 * Appends the string representation of the {@code boolean}
750 * argument to the sequence.
751 * <p>
752 * The overall effect is exactly as if the argument were converted
753 * to a string by the method {@link String#valueOf(boolean)},
754 * and the characters of that string were then
755 * {@link #append(String) appended} to this character sequence.
756 *
757 * @param b a {@code boolean}.
758 * @return a reference to this object.
759 */
760 public AbstractStringBuilder append(boolean b) {
761 ensureCapacityInternal(count + (b ? 4 : 5));
762 int count = this.count;
763 byte[] val = this.value;
764 if (isLatin1()) {
765 if (b) {
766 val[count++] = 't';
767 val[count++] = 'r';
768 val[count++] = 'u';
769 val[count++] = 'e';
770 } else {
771 val[count++] = 'f';
772 val[count++] = 'a';
773 val[count++] = 'l';
774 val[count++] = 's';
775 val[count++] = 'e';
776 }
777 } else {
778 if (b) {
779 count = StringUTF16.putCharsAt(val, count, 't', 'r', 'u', 'e');
780 } else {
781 count = StringUTF16.putCharsAt(val, count, 'f', 'a', 'l', 's', 'e');
782 }
783 }
784 this.count = count;
785 return this;
786 }
787
788 /**
789 * Appends the string representation of the {@code char}
790 * argument to this sequence.
791 * <p>
792 * The argument is appended to the contents of this sequence.
793 * The length of this sequence increases by {@code 1}.
794 * <p>
795 * The overall effect is exactly as if the argument were converted
796 * to a string by the method {@link String#valueOf(char)},
797 * and the character in that string were then
798 * {@link #append(String) appended} to this character sequence.
799 *
800 * @param c a {@code char}.
801 * @return a reference to this object.
802 */
803 @Override
804 public AbstractStringBuilder append(char c) {
805 ensureCapacityInternal(count + 1);
806 if (isLatin1() && StringLatin1.canEncode(c)) {
807 value[count++] = (byte)c;
808 } else {
809 if (isLatin1()) {
810 inflate();
811 }
812 StringUTF16.putCharSB(value, count++, c);
813 }
814 return this;
815 }
816
817 /**
818 * Appends the string representation of the {@code int}
819 * argument to this sequence.
820 * <p>
821 * The overall effect is exactly as if the argument were converted
822 * to a string by the method {@link String#valueOf(int)},
823 * and the characters of that string were then
824 * {@link #append(String) appended} to this character sequence.
825 *
826 * @param i an {@code int}.
827 * @return a reference to this object.
828 */
829 public AbstractStringBuilder append(int i) {
830 int count = this.count;
831 int spaceNeeded = count + Integer.stringSize(i);
832 ensureCapacityInternal(spaceNeeded);
833 if (isLatin1()) {
834 Integer.getChars(i, spaceNeeded, value);
835 } else {
836 StringUTF16.getChars(i, count, spaceNeeded, value);
837 }
838 this.count = spaceNeeded;
839 return this;
840 }
841
842 /**
843 * Appends the string representation of the {@code long}
844 * argument to this sequence.
845 * <p>
846 * The overall effect is exactly as if the argument were converted
847 * to a string by the method {@link String#valueOf(long)},
848 * and the characters of that string were then
849 * {@link #append(String) appended} to this character sequence.
850 *
851 * @param l a {@code long}.
852 * @return a reference to this object.
853 */
854 public AbstractStringBuilder append(long l) {
855 int count = this.count;
856 int spaceNeeded = count + Long.stringSize(l);
857 ensureCapacityInternal(spaceNeeded);
858 if (isLatin1()) {
859 Long.getChars(l, spaceNeeded, value);
860 } else {
861 StringUTF16.getChars(l, count, spaceNeeded, value);
862 }
863 this.count = spaceNeeded;
864 return this;
865 }
866
867 /**
868 * Appends the string representation of the {@code float}
869 * argument to this sequence.
870 * <p>
871 * The overall effect is exactly as if the argument were converted
872 * to a string by the method {@link String#valueOf(float)},
873 * and the characters of that string were then
874 * {@link #append(String) appended} to this character sequence.
875 *
876 * @param f a {@code float}.
877 * @return a reference to this object.
878 */
879 public AbstractStringBuilder append(float f) {
880 try {
881 FloatToDecimal.appendTo(f, this);
882 } catch (IOException ignored) {
883 assert false;
884 }
885 return this;
886 }
887
888 /**
889 * Appends the string representation of the {@code double}
890 * argument to this sequence.
891 * <p>
892 * The overall effect is exactly as if the argument were converted
893 * to a string by the method {@link String#valueOf(double)},
894 * and the characters of that string were then
895 * {@link #append(String) appended} to this character sequence.
896 *
897 * @param d a {@code double}.
898 * @return a reference to this object.
899 */
900 public AbstractStringBuilder append(double d) {
901 try {
902 DoubleToDecimal.appendTo(d, this);
903 } catch (IOException ignored) {
904 assert false;
905 }
906 return this;
907 }
908
909 /**
910 * Removes the characters in a substring of this sequence.
911 * The substring begins at the specified {@code start} and extends to
912 * the character at index {@code end - 1} or to the end of the
913 * sequence if no such character exists. If
914 * {@code start} is equal to {@code end}, no changes are made.
915 *
916 * @param start The beginning index, inclusive.
917 * @param end The ending index, exclusive.
918 * @return This object.
919 * @throws StringIndexOutOfBoundsException if {@code start}
920 * is negative, greater than {@code length()}, or
921 * greater than {@code end}.
922 */
923 public AbstractStringBuilder delete(int start, int end) {
924 int count = this.count;
925 if (end > count) {
926 end = count;
927 }
928 checkRangeSIOOBE(start, end, count);
929 int len = end - start;
930 if (len > 0) {
931 shift(end, -len);
932 this.count = count - len;
933 }
934 return this;
935 }
936
937 /**
938 * Appends the string representation of the {@code codePoint}
939 * argument to this sequence.
940 *
941 * <p> The argument is appended to the contents of this sequence.
942 * The length of this sequence increases by
943 * {@link Character#charCount(int) Character.charCount(codePoint)}.
944 *
945 * <p> The overall effect is exactly as if the argument were
946 * converted to a {@code char} array by the method
947 * {@link Character#toChars(int)} and the character in that array
948 * were then {@link #append(char[]) appended} to this character
949 * sequence.
950 *
951 * @param codePoint a Unicode code point
952 * @return a reference to this object.
953 * @throws IllegalArgumentException if the specified
954 * {@code codePoint} isn't a valid Unicode code point
955 */
956 public AbstractStringBuilder appendCodePoint(int codePoint) {
957 if (Character.isBmpCodePoint(codePoint)) {
958 return append((char)codePoint);
959 }
960 return append(Character.toChars(codePoint));
961 }
962
963 /**
964 * Removes the {@code char} at the specified position in this
965 * sequence. This sequence is shortened by one {@code char}.
966 *
967 * <p>Note: If the character at the given index is a supplementary
968 * character, this method does not remove the entire character. If
969 * correct handling of supplementary characters is required,
970 * determine the number of {@code char}s to remove by calling
971 * {@code Character.charCount(thisSequence.codePointAt(index))},
972 * where {@code thisSequence} is this sequence.
973 *
974 * @param index Index of {@code char} to remove
975 * @return This object.
976 * @throws StringIndexOutOfBoundsException if the {@code index}
977 * is negative or greater than or equal to
978 * {@code length()}.
979 */
980 public AbstractStringBuilder deleteCharAt(int index) {
981 checkIndex(index, count);
982 shift(index + 1, -1);
983 count--;
984 return this;
985 }
986
987 /**
988 * Replaces the characters in a substring of this sequence
989 * with characters in the specified {@code String}. The substring
990 * begins at the specified {@code start} and extends to the character
991 * at index {@code end - 1} or to the end of the
992 * sequence if no such character exists. First the
993 * characters in the substring are removed and then the specified
994 * {@code String} is inserted at {@code start}. (This
995 * sequence will be lengthened to accommodate the
996 * specified String if necessary.)
997 *
998 * @param start The beginning index, inclusive.
999 * @param end The ending index, exclusive.
1000 * @param str String that will replace previous contents.
1001 * @return This object.
1002 * @throws StringIndexOutOfBoundsException if {@code start}
1003 * is negative, greater than {@code length()}, or
1004 * greater than {@code end}.
1005 */
1006 public AbstractStringBuilder replace(int start, int end, String str) {
1007 int count = this.count;
1008 if (end > count) {
1009 end = count;
1010 }
1011 checkRangeSIOOBE(start, end, count);
1012 int len = str.length();
1013 int newCount = count + len - (end - start);
1014 ensureCapacityInternal(newCount);
1015 shift(end, newCount - count);
1016 this.count = newCount;
1017 putStringAt(start, str);
1018 return this;
1019 }
1020
1021 /**
1022 * Returns a new {@code String} that contains a subsequence of
1023 * characters currently contained in this character sequence. The
1024 * substring begins at the specified index and extends to the end of
1025 * this sequence.
1026 *
1027 * @param start The beginning index, inclusive.
1028 * @return The new string.
1029 * @throws StringIndexOutOfBoundsException if {@code start} is
1030 * less than zero, or greater than the length of this object.
1031 */
1032 public String substring(int start) {
1033 return substring(start, count);
1034 }
1035
1036 /**
1037 * Returns a new character sequence that is a subsequence of this sequence.
1038 *
1039 * <p> An invocation of this method of the form
1040 *
1041 * <pre>{@code
1042 * sb.subSequence(begin, end)}</pre>
1043 *
1044 * behaves in exactly the same way as the invocation
1045 *
1046 * <pre>{@code
1047 * sb.substring(begin, end)}</pre>
1048 *
1049 * This method is provided so that this class can
1050 * implement the {@link CharSequence} interface.
1051 *
1052 * @param start the start index, inclusive.
1053 * @param end the end index, exclusive.
1054 * @return the specified subsequence.
1055 *
1056 * @throws IndexOutOfBoundsException
1057 * if {@code start} or {@code end} are negative,
1058 * if {@code end} is greater than {@code length()},
1059 * or if {@code start} is greater than {@code end}
1060 * @spec JSR-51
1061 */
1062 @Override
1063 public CharSequence subSequence(int start, int end) {
1064 return substring(start, end);
1065 }
1066
1067 /**
1068 * Returns a new {@code String} that contains a subsequence of
1069 * characters currently contained in this sequence. The
1070 * substring begins at the specified {@code start} and
1071 * extends to the character at index {@code end - 1}.
1072 *
1073 * @param start The beginning index, inclusive.
1074 * @param end The ending index, exclusive.
1075 * @return The new string.
1076 * @throws StringIndexOutOfBoundsException if {@code start}
1077 * or {@code end} are negative or greater than
1078 * {@code length()}, or {@code start} is
1079 * greater than {@code end}.
1080 */
1081 public String substring(int start, int end) {
1082 checkRangeSIOOBE(start, end, count);
1083 if (isLatin1()) {
1084 return StringLatin1.newString(value, start, end - start);
1085 }
1086 return StringUTF16.newString(value, start, end - start);
1087 }
1088
1089 private void shift(int offset, int n) {
1090 System.arraycopy(value, offset << coder,
1091 value, (offset + n) << coder, (count - offset) << coder);
1092 }
1093
1094 /**
1095 * Inserts the string representation of a subarray of the {@code str}
1096 * array argument into this sequence. The subarray begins at the
1097 * specified {@code offset} and extends {@code len} {@code char}s.
1098 * The characters of the subarray are inserted into this sequence at
1099 * the position indicated by {@code index}. The length of this
1100 * sequence increases by {@code len} {@code char}s.
1101 *
1102 * @param index position at which to insert subarray.
1103 * @param str A {@code char} array.
1104 * @param offset the index of the first {@code char} in subarray to
1105 * be inserted.
1106 * @param len the number of {@code char}s in the subarray to
1107 * be inserted.
1108 * @return This object
1109 * @throws StringIndexOutOfBoundsException if {@code index}
1110 * is negative or greater than {@code length()}, or
1111 * {@code offset} or {@code len} are negative, or
1112 * {@code (offset+len)} is greater than
1113 * {@code str.length}.
1114 */
1115 public AbstractStringBuilder insert(int index, char[] str, int offset,
1116 int len)
1117 {
1118 checkOffset(index, count);
1119 checkRangeSIOOBE(offset, offset + len, str.length);
1120 ensureCapacityInternal(count + len);
1121 shift(index, len);
1122 count += len;
1123 putCharsAt(index, str, offset, offset + len);
1124 return this;
1125 }
1126
1127 /**
1128 * Inserts the string representation of the {@code Object}
1129 * argument into this character sequence.
1130 * <p>
1131 * The overall effect is exactly as if the second argument were
1132 * converted to a string by the method {@link String#valueOf(Object)},
1133 * and the characters of that string were then
1134 * {@link #insert(int,String) inserted} into this character
1135 * sequence at the indicated offset.
1136 * <p>
1137 * The {@code offset} argument must be greater than or equal to
1138 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1139 * of this sequence.
1140 *
1141 * @param offset the offset.
1142 * @param obj an {@code Object}.
1143 * @return a reference to this object.
1144 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1145 */
1146 public AbstractStringBuilder insert(int offset, Object obj) {
1147 return insert(offset, String.valueOf(obj));
1148 }
1149
1150 /**
1151 * Inserts the string into this character sequence.
1152 * <p>
1153 * The characters of the {@code String} argument are inserted, in
1154 * order, into this sequence at the indicated offset, moving up any
1155 * characters originally above that position and increasing the length
1156 * of this sequence by the length of the argument. If
1157 * {@code str} is {@code null}, then the four characters
1158 * {@code "null"} are inserted into this sequence.
1159 * <p>
1160 * The character at index <i>k</i> in the new character sequence is
1161 * equal to:
1162 * <ul>
1163 * <li>the character at index <i>k</i> in the old character sequence, if
1164 * <i>k</i> is less than {@code offset}
1165 * <li>the character at index <i>k</i>{@code -offset} in the
1166 * argument {@code str}, if <i>k</i> is not less than
1167 * {@code offset} but is less than {@code offset+str.length()}
1168 * <li>the character at index <i>k</i>{@code -str.length()} in the
1169 * old character sequence, if <i>k</i> is not less than
1170 * {@code offset+str.length()}
1171 * </ul><p>
1172 * The {@code offset} argument must be greater than or equal to
1173 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1174 * of this sequence.
1175 *
1176 * @param offset the offset.
1177 * @param str a string.
1178 * @return a reference to this object.
1179 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1180 */
1181 public AbstractStringBuilder insert(int offset, String str) {
1182 checkOffset(offset, count);
1183 if (str == null) {
1184 str = "null";
1185 }
1186 int len = str.length();
1187 ensureCapacityInternal(count + len);
1188 shift(offset, len);
1189 count += len;
1190 putStringAt(offset, str);
1191 return this;
1192 }
1193
1194 /**
1195 * Inserts the string representation of the {@code char} array
1196 * argument into this sequence.
1197 * <p>
1198 * The characters of the array argument are inserted into the
1199 * contents of this sequence at the position indicated by
1200 * {@code offset}. The length of this sequence increases by
1201 * the length of the argument.
1202 * <p>
1203 * The overall effect is exactly as if the second argument were
1204 * converted to a string by the method {@link String#valueOf(char[])},
1205 * and the characters of that string were then
1206 * {@link #insert(int,String) inserted} into this character
1207 * sequence at the indicated offset.
1208 * <p>
1209 * The {@code offset} argument must be greater than or equal to
1210 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1211 * of this sequence.
1212 *
1213 * @param offset the offset.
1214 * @param str a character array.
1215 * @return a reference to this object.
1216 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1217 */
1218 public AbstractStringBuilder insert(int offset, char[] str) {
1219 checkOffset(offset, count);
1220 int len = str.length;
1221 ensureCapacityInternal(count + len);
1222 shift(offset, len);
1223 count += len;
1224 putCharsAt(offset, str, 0, len);
1225 return this;
1226 }
1227
1228 /**
1229 * Inserts the specified {@code CharSequence} into this sequence.
1230 * <p>
1231 * The characters of the {@code CharSequence} argument are inserted,
1232 * in order, into this sequence at the indicated offset, moving up
1233 * any characters originally above that position and increasing the length
1234 * of this sequence by the length of the argument s.
1235 * <p>
1236 * The result of this method is exactly the same as if it were an
1237 * invocation of this object's
1238 * {@link #insert(int,CharSequence,int,int) insert}(dstOffset, s, 0, s.length())
1239 * method.
1240 *
1241 * <p>If {@code s} is {@code null}, then the four characters
1242 * {@code "null"} are inserted into this sequence.
1243 *
1244 * @param dstOffset the offset.
1245 * @param s the sequence to be inserted
1246 * @return a reference to this object.
1247 * @throws IndexOutOfBoundsException if the offset is invalid.
1248 */
1249 public AbstractStringBuilder insert(int dstOffset, CharSequence s) {
1250 if (s == null) {
1251 s = "null";
1252 }
1253 if (s instanceof String) {
1254 return this.insert(dstOffset, (String)s);
1255 }
1256 return this.insert(dstOffset, s, 0, s.length());
1257 }
1258
1259 /**
1260 * Inserts a subsequence of the specified {@code CharSequence} into
1261 * this sequence.
1262 * <p>
1263 * The subsequence of the argument {@code s} specified by
1264 * {@code start} and {@code end} are inserted,
1265 * in order, into this sequence at the specified destination offset, moving
1266 * up any characters originally above that position. The length of this
1267 * sequence is increased by {@code end - start}.
1268 * <p>
1269 * The character at index <i>k</i> in this sequence becomes equal to:
1270 * <ul>
1271 * <li>the character at index <i>k</i> in this sequence, if
1272 * <i>k</i> is less than {@code dstOffset}
1273 * <li>the character at index <i>k</i>{@code +start-dstOffset} in
1274 * the argument {@code s}, if <i>k</i> is greater than or equal to
1275 * {@code dstOffset} but is less than {@code dstOffset+end-start}
1276 * <li>the character at index <i>k</i>{@code -(end-start)} in this
1277 * sequence, if <i>k</i> is greater than or equal to
1278 * {@code dstOffset+end-start}
1279 * </ul><p>
1280 * The {@code dstOffset} argument must be greater than or equal to
1281 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1282 * of this sequence.
1283 * <p>The start argument must be nonnegative, and not greater than
1284 * {@code end}.
1285 * <p>The end argument must be greater than or equal to
1286 * {@code start}, and less than or equal to the length of s.
1287 *
1288 * <p>If {@code s} is {@code null}, then this method inserts
1289 * characters as if the s parameter was a sequence containing the four
1290 * characters {@code "null"}.
1291 *
1292 * @param dstOffset the offset in this sequence.
1293 * @param s the sequence to be inserted.
1294 * @param start the starting index of the subsequence to be inserted.
1295 * @param end the end index of the subsequence to be inserted.
1296 * @return a reference to this object.
1297 * @throws IndexOutOfBoundsException if {@code dstOffset}
1298 * is negative or greater than {@code this.length()}, or
1299 * {@code start} or {@code end} are negative, or
1300 * {@code start} is greater than {@code end} or
1301 * {@code end} is greater than {@code s.length()}
1302 */
1303 public AbstractStringBuilder insert(int dstOffset, CharSequence s,
1304 int start, int end)
1305 {
1306 if (s == null) {
1307 s = "null";
1308 }
1309 checkOffset(dstOffset, count);
1310 checkRange(start, end, s.length());
1311 int len = end - start;
1312 ensureCapacityInternal(count + len);
1313 shift(dstOffset, len);
1314 count += len;
1315 putCharsAt(dstOffset, s, start, end);
1316 return this;
1317 }
1318
1319 /**
1320 * Inserts the string representation of the {@code boolean}
1321 * argument into this sequence.
1322 * <p>
1323 * The overall effect is exactly as if the second argument were
1324 * converted to a string by the method {@link String#valueOf(boolean)},
1325 * and the characters of that string were then
1326 * {@link #insert(int,String) inserted} into this character
1327 * sequence at the indicated offset.
1328 * <p>
1329 * The {@code offset} argument must be greater than or equal to
1330 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1331 * of this sequence.
1332 *
1333 * @param offset the offset.
1334 * @param b a {@code boolean}.
1335 * @return a reference to this object.
1336 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1337 */
1338 public AbstractStringBuilder insert(int offset, boolean b) {
1339 return insert(offset, String.valueOf(b));
1340 }
1341
1342 /**
1343 * Inserts the string representation of the {@code char}
1344 * argument into this sequence.
1345 * <p>
1346 * The overall effect is exactly as if the second argument were
1347 * converted to a string by the method {@link String#valueOf(char)},
1348 * and the character in that string were then
1349 * {@link #insert(int,String) inserted} into this character
1350 * sequence at the indicated offset.
1351 * <p>
1352 * The {@code offset} argument must be greater than or equal to
1353 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1354 * of this sequence.
1355 *
1356 * @param offset the offset.
1357 * @param c a {@code char}.
1358 * @return a reference to this object.
1359 * @throws IndexOutOfBoundsException if the offset is invalid.
1360 */
1361 public AbstractStringBuilder insert(int offset, char c) {
1362 checkOffset(offset, count);
1363 ensureCapacityInternal(count + 1);
1364 shift(offset, 1);
1365 count += 1;
1366 if (isLatin1() && StringLatin1.canEncode(c)) {
1367 value[offset] = (byte)c;
1368 } else {
1369 if (isLatin1()) {
1370 inflate();
1371 }
1372 StringUTF16.putCharSB(value, offset, c);
1373 }
1374 return this;
1375 }
1376
1377 /**
1378 * Inserts the string representation of the second {@code int}
1379 * argument into this sequence.
1380 * <p>
1381 * The overall effect is exactly as if the second argument were
1382 * converted to a string by the method {@link String#valueOf(int)},
1383 * and the characters of that string were then
1384 * {@link #insert(int,String) inserted} into this character
1385 * sequence at the indicated offset.
1386 * <p>
1387 * The {@code offset} argument must be greater than or equal to
1388 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1389 * of this sequence.
1390 *
1391 * @param offset the offset.
1392 * @param i an {@code int}.
1393 * @return a reference to this object.
1394 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1395 */
1396 public AbstractStringBuilder insert(int offset, int i) {
1397 return insert(offset, String.valueOf(i));
1398 }
1399
1400 /**
1401 * Inserts the string representation of the {@code long}
1402 * argument into this sequence.
1403 * <p>
1404 * The overall effect is exactly as if the second argument were
1405 * converted to a string by the method {@link String#valueOf(long)},
1406 * and the characters of that string were then
1407 * {@link #insert(int,String) inserted} into this character
1408 * sequence at the indicated offset.
1409 * <p>
1410 * The {@code offset} argument must be greater than or equal to
1411 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1412 * of this sequence.
1413 *
1414 * @param offset the offset.
1415 * @param l a {@code long}.
1416 * @return a reference to this object.
1417 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1418 */
1419 public AbstractStringBuilder insert(int offset, long l) {
1420 return insert(offset, String.valueOf(l));
1421 }
1422
1423 /**
1424 * Inserts the string representation of the {@code float}
1425 * argument into this sequence.
1426 * <p>
1427 * The overall effect is exactly as if the second argument were
1428 * converted to a string by the method {@link String#valueOf(float)},
1429 * and the characters of that string were then
1430 * {@link #insert(int,String) inserted} into this character
1431 * sequence at the indicated offset.
1432 * <p>
1433 * The {@code offset} argument must be greater than or equal to
1434 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1435 * of this sequence.
1436 *
1437 * @param offset the offset.
1438 * @param f a {@code float}.
1439 * @return a reference to this object.
1440 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1441 */
1442 public AbstractStringBuilder insert(int offset, float f) {
1443 return insert(offset, String.valueOf(f));
1444 }
1445
1446 /**
1447 * Inserts the string representation of the {@code double}
1448 * argument into this sequence.
1449 * <p>
1450 * The overall effect is exactly as if the second argument were
1451 * converted to a string by the method {@link String#valueOf(double)},
1452 * and the characters of that string were then
1453 * {@link #insert(int,String) inserted} into this character
1454 * sequence at the indicated offset.
1455 * <p>
1456 * The {@code offset} argument must be greater than or equal to
1457 * {@code 0}, and less than or equal to the {@linkplain #length() length}
1458 * of this sequence.
1459 *
1460 * @param offset the offset.
1461 * @param d a {@code double}.
1462 * @return a reference to this object.
1463 * @throws StringIndexOutOfBoundsException if the offset is invalid.
1464 */
1465 public AbstractStringBuilder insert(int offset, double d) {
1466 return insert(offset, String.valueOf(d));
1467 }
1468
1469 /**
1470 * Returns the index within this string of the first occurrence of the
1471 * specified substring.
1472 *
1473 * <p>The returned index is the smallest value {@code k} for which:
1474 * <pre>{@code
1475 * this.toString().startsWith(str, k)
1476 * }</pre>
1477 * If no such value of {@code k} exists, then {@code -1} is returned.
1478 *
1479 * @param str the substring to search for.
1480 * @return the index of the first occurrence of the specified substring,
1481 * or {@code -1} if there is no such occurrence.
1482 */
1483 public int indexOf(String str) {
1484 return indexOf(str, 0);
1485 }
1486
1487 /**
1488 * Returns the index within this string of the first occurrence of the
1489 * specified substring, starting at the specified index.
1490 *
1491 * <p>The returned index is the smallest value {@code k} for which:
1492 * <pre>{@code
1493 * k >= Math.min(fromIndex, this.length()) &&
1494 * this.toString().startsWith(str, k)
1495 * }</pre>
1496 * If no such value of {@code k} exists, then {@code -1} is returned.
1497 *
1498 * @param str the substring to search for.
1499 * @param fromIndex the index from which to start the search.
1500 * @return the index of the first occurrence of the specified substring,
1501 * starting at the specified index,
1502 * or {@code -1} if there is no such occurrence.
1503 */
1504 public int indexOf(String str, int fromIndex) {
1505 return String.indexOf(value, coder, count, str, fromIndex);
1506 }
1507
1508 /**
1509 * Returns the index within this string of the last occurrence of the
1510 * specified substring. The last occurrence of the empty string "" is
1511 * considered to occur at the index value {@code this.length()}.
1512 *
1513 * <p>The returned index is the largest value {@code k} for which:
1514 * <pre>{@code
1515 * this.toString().startsWith(str, k)
1516 * }</pre>
1517 * If no such value of {@code k} exists, then {@code -1} is returned.
1518 *
1519 * @param str the substring to search for.
1520 * @return the index of the last occurrence of the specified substring,
1521 * or {@code -1} if there is no such occurrence.
1522 */
1523 public int lastIndexOf(String str) {
1524 return lastIndexOf(str, count);
1525 }
1526
1527 /**
1528 * Returns the index within this string of the last occurrence of the
1529 * specified substring, searching backward starting at the specified index.
1530 *
1531 * <p>The returned index is the largest value {@code k} for which:
1532 * <pre>{@code
1533 * k <= Math.min(fromIndex, this.length()) &&
1534 * this.toString().startsWith(str, k)
1535 * }</pre>
1536 * If no such value of {@code k} exists, then {@code -1} is returned.
1537 *
1538 * @param str the substring to search for.
1539 * @param fromIndex the index to start the search from.
1540 * @return the index of the last occurrence of the specified substring,
1541 * searching backward from the specified index,
1542 * or {@code -1} if there is no such occurrence.
1543 */
1544 public int lastIndexOf(String str, int fromIndex) {
1545 return String.lastIndexOf(value, coder, count, str, fromIndex);
1546 }
1547
1548 /**
1549 * Causes this character sequence to be replaced by the reverse of
1550 * the sequence. If there are any surrogate pairs included in the
1551 * sequence, these are treated as single characters for the
1552 * reverse operation. Thus, the order of the high-low surrogates
1553 * is never reversed.
1554 *
1555 * Let <i>n</i> be the character length of this character sequence
1556 * (not the length in {@code char} values) just prior to
1557 * execution of the {@code reverse} method. Then the
1558 * character at index <i>k</i> in the new character sequence is
1559 * equal to the character at index <i>n-k-1</i> in the old
1560 * character sequence.
1561 *
1562 * <p>Note that the reverse operation may result in producing
1563 * surrogate pairs that were unpaired low-surrogates and
1564 * high-surrogates before the operation. For example, reversing
1565 * "\u005CuDC00\u005CuD800" produces "\u005CuD800\u005CuDC00" which is
1566 * a valid surrogate pair.
1567 *
1568 * @return a reference to this object.
1569 */
1570 public AbstractStringBuilder reverse() {
1571 byte[] val = this.value;
1572 int count = this.count;
1573 int coder = this.coder;
1574 int n = count - 1;
1575 if (COMPACT_STRINGS && coder == LATIN1) {
1576 for (int j = (n-1) >> 1; j >= 0; j--) {
1577 int k = n - j;
1578 byte cj = val[j];
1579 val[j] = val[k];
1580 val[k] = cj;
1581 }
1582 } else {
1583 StringUTF16.reverse(val, count);
1584 }
1585 return this;
1586 }
1587
1588 /**
1589 * Returns a string representing the data in this sequence.
1590 * A new {@code String} object is allocated and initialized to
1591 * contain the character sequence currently represented by this
1592 * object. This {@code String} is then returned. Subsequent
1593 * changes to this sequence do not affect the contents of the
1594 * {@code String}.
1595 *
1596 * @return a string representation of this sequence of characters.
1597 */
1598 @Override
1599 public abstract String toString();
1600
1601 /**
1602 * {@inheritDoc}
1603 * @since 9
1604 */
1605 @Override
1606 public IntStream chars() {
1607 // Reuse String-based spliterator. This requires a supplier to
1608 // capture the value and count when the terminal operation is executed
1609 return StreamSupport.intStream(
1610 () -> {
1611 // The combined set of field reads are not atomic and thread
1612 // safe but bounds checks will ensure no unsafe reads from
1613 // the byte array
1614 byte[] val = this.value;
1615 int count = this.count;
1616 byte coder = this.coder;
1617 return coder == LATIN1
1618 ? new StringLatin1.CharsSpliterator(val, 0, count, 0)
1619 : new StringUTF16.CharsSpliterator(val, 0, count, 0);
1620 },
1621 Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED,
1622 false);
1623 }
1624
1625 /**
1626 * {@inheritDoc}
1627 * @since 9
1628 */
1629 @Override
1630 public IntStream codePoints() {
1631 // Reuse String-based spliterator. This requires a supplier to
1632 // capture the value and count when the terminal operation is executed
1633 return StreamSupport.intStream(
1634 () -> {
1635 // The combined set of field reads are not atomic and thread
1636 // safe but bounds checks will ensure no unsafe reads from
1637 // the byte array
1638 byte[] val = this.value;
1639 int count = this.count;
1640 byte coder = this.coder;
1641 return coder == LATIN1
1642 ? new StringLatin1.CharsSpliterator(val, 0, count, 0)
1643 : new StringUTF16.CodePointsSpliterator(val, 0, count, 0);
1644 },
1645 Spliterator.ORDERED,
1646 false);
1647 }
1648
1649 /**
1650 * Needed by {@code String} for the contentEquals method.
1651 */
1652 final byte[] getValue() {
1653 return value;
1654 }
1655
1656 /*
1657 * Invoker guarantees it is in UTF16 (inflate itself for asb), if two
1658 * coders are different and the dstBegin has enough space
1659 *
1660 * @param dstBegin the char index, not offset of byte[]
1661 * @param coder the coder of dst[]
1662 */
1663 void getBytes(byte dst[], int dstBegin, byte coder) {
1664 if (this.coder == coder) {
1665 System.arraycopy(value, 0, dst, dstBegin << coder, count << coder);
1666 } else { // this.coder == LATIN && coder == UTF16
1667 StringLatin1.inflate(value, 0, dst, dstBegin, count);
1668 }
1669 }
1670
1671 /* for readObject() */
1672 void initBytes(char[] value, int off, int len) {
1673 if (String.COMPACT_STRINGS) {
1674 this.value = StringUTF16.compress(value, off, len);
1675 if (this.value != null) {
1676 this.coder = LATIN1;
1677 return;
1678 }
1679 }
1680 this.coder = UTF16;
1681 this.value = StringUTF16.toBytes(value, off, len);
1682 }
1683
1684 final byte getCoder() {
1685 return COMPACT_STRINGS ? coder : UTF16;
1686 }
1687
1688 final boolean isLatin1() {
1689 return COMPACT_STRINGS && coder == LATIN1;
1690 }
1691
1692 private final void putCharsAt(int index, char[] s, int off, int end) {
1693 if (isLatin1()) {
1694 byte[] val = this.value;
1695 for (int i = off, j = index; i < end; i++) {
1696 char c = s[i];
1697 if (StringLatin1.canEncode(c)) {
1698 val[j++] = (byte)c;
1699 } else {
1700 inflate();
1701 StringUTF16.putCharsSB(this.value, j, s, i, end);
1702 return;
1703 }
1704 }
1705 } else {
1706 StringUTF16.putCharsSB(this.value, index, s, off, end);
1707 }
1708 }
1709
1710 private final void putCharsAt(int index, CharSequence s, int off, int end) {
1711 if (isLatin1()) {
1712 byte[] val = this.value;
1713 for (int i = off, j = index; i < end; i++) {
1714 char c = s.charAt(i);
1715 if (StringLatin1.canEncode(c)) {
1716 val[j++] = (byte)c;
1717 } else {
1718 inflate();
1719 StringUTF16.putCharsSB(this.value, j, s, i, end);
1720 return;
1721 }
1722 }
1723 } else {
1724 StringUTF16.putCharsSB(this.value, index, s, off, end);
1725 }
1726 }
1727
1728 private final void putStringAt(int index, String str) {
1729 if (getCoder() != str.coder()) {
1730 inflate();
1731 }
1732 str.getBytes(value, index, coder);
1733 }
1734
1735 private final void appendChars(char[] s, int off, int end) {
1736 int count = this.count;
1737 if (isLatin1()) {
1738 byte[] val = this.value;
1739 for (int i = off, j = count; i < end; i++) {
1740 char c = s[i];
1741 if (StringLatin1.canEncode(c)) {
1742 val[j++] = (byte)c;
1743 } else {
1744 this.count = count = j;
1745 inflate();
1746 StringUTF16.putCharsSB(this.value, j, s, i, end);
1747 this.count = count + end - i;
1748 return;
1749 }
1750 }
1751 } else {
1752 StringUTF16.putCharsSB(this.value, count, s, off, end);
1753 }
1754 this.count = count + end - off;
1755 }
1756
1757 private final void appendChars(CharSequence s, int off, int end) {
1758 if (isLatin1()) {
1759 byte[] val = this.value;
1760 for (int i = off, j = count; i < end; i++) {
1761 char c = s.charAt(i);
1762 if (StringLatin1.canEncode(c)) {
1763 val[j++] = (byte)c;
1764 } else {
1765 count = j;
1766 inflate();
1767 StringUTF16.putCharsSB(this.value, j, s, i, end);
1768 count += end - i;
1769 return;
1770 }
1771 }
1772 } else {
1773 StringUTF16.putCharsSB(this.value, count, s, off, end);
1774 }
1775 count += end - off;
1776 }
1777
1778 /* IndexOutOfBoundsException, if out of bounds */
1779 private static void checkRange(int start, int end, int len) {
1780 if (start < 0 || start > end || end > len) {
1781 throw new IndexOutOfBoundsException(
1782 "start " + start + ", end " + end + ", length " + len);
1783 }
1784 }
1785
1786 /* StringIndexOutOfBoundsException, if out of bounds */
1787 private static void checkRangeSIOOBE(int start, int end, int len) {
1788 if (start < 0 || start > end || end > len) {
1789 throw new StringIndexOutOfBoundsException(
1790 "start " + start + ", end " + end + ", length " + len);
1791 }
1792 }
1793 }