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AbstractStringBuilder.java
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AbstractStringBuilder.java
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/*
* Copyright (c) 2003, 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.lang;
import jdk.internal.math.DoubleToDecimal;
import jdk.internal.math.FloatToDecimal;
import java.io.IOException;
import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.Spliterator;
import java.util.stream.IntStream;
import java.util.stream.StreamSupport;
import jdk.internal.util.ArraysSupport;
import jdk.internal.util.Preconditions;
import static java.lang.String.COMPACT_STRINGS;
import static java.lang.String.UTF16;
import static java.lang.String.LATIN1;
import static java.lang.String.checkIndex;
import static java.lang.String.checkOffset;
/**
* A mutable sequence of characters.
* <p>
* Implements a modifiable string. At any point in time it contains some
* particular sequence of characters, but the length and content of the
* sequence can be changed through certain method calls.
*
* <p>Unless otherwise noted, passing a {@code null} argument to a constructor
* or method in this class will cause a {@link NullPointerException} to be
* thrown.
*
* @author Michael McCloskey
* @author Martin Buchholz
* @author Ulf Zibis
* @since 1.5
*/
abstract sealed class AbstractStringBuilder implements Appendable, CharSequence
permits StringBuilder, StringBuffer {
/**
* The value is used for character storage.
*/
byte[] value;
/**
* The id of the encoding used to encode the bytes in {@code value}.
*/
byte coder;
/**
* The attribute indicates {@code value} might be compressible to LATIN1 if it is UTF16-encoded.
* An inflated byte array becomes compressible only when those non-latin1 chars are deleted.
* We simply set this attribute in all methods which may delete chars. Therefore, there are
* false positives. Subclasses and String need to handle it properly.
*/
boolean maybeLatin1;
/**
* The count is the number of characters used.
*/
int count;
private static final byte[] EMPTYVALUE = new byte[0];
/**
* This no-arg constructor is necessary for serialization of subclasses.
*/
AbstractStringBuilder() {
value = EMPTYVALUE;
}
/**
* Creates an AbstractStringBuilder of the specified capacity.
*/
AbstractStringBuilder(int capacity) {
if (COMPACT_STRINGS) {
value = new byte[capacity];
coder = LATIN1;
} else {
value = StringUTF16.newBytesFor(capacity);
coder = UTF16;
}
}
/**
* Constructs an AbstractStringBuilder that contains the same characters
* as the specified {@code String}. The initial capacity of
* the string builder is {@code 16} plus the length of the
* {@code String} argument.
*
* @param str the string to copy.
*/
AbstractStringBuilder(String str) {
int length = str.length();
int capacity = (length < Integer.MAX_VALUE - 16)
? length + 16 : Integer.MAX_VALUE;
final byte initCoder = str.coder();
coder = initCoder;
value = (initCoder == LATIN1)
? new byte[capacity] : StringUTF16.newBytesFor(capacity);
append(str);
}
/**
* Constructs an AbstractStringBuilder that contains the same characters
* as the specified {@code CharSequence}. The initial capacity of
* the string builder is {@code 16} plus the length of the
* {@code CharSequence} argument.
* <p>
* The contents are unspecified if the {@code CharSequence}
* is modified during string construction.
*
* @param seq the sequence to copy.
*/
AbstractStringBuilder(CharSequence seq) {
int length = seq.length();
if (length < 0) {
throw new NegativeArraySizeException("Negative length: " + length);
}
int capacity = (length < Integer.MAX_VALUE - 16)
? length + 16 : Integer.MAX_VALUE;
final byte initCoder;
if (COMPACT_STRINGS) {
if (seq instanceof AbstractStringBuilder asb) {
initCoder = asb.getCoder();
maybeLatin1 |= asb.maybeLatin1;
} else if (seq instanceof String s) {
initCoder = s.coder();
} else {
initCoder = LATIN1;
}
} else {
initCoder = UTF16;
}
coder = initCoder;
value = (initCoder == LATIN1)
? new byte[capacity] : StringUTF16.newBytesFor(capacity);
append(seq);
}
/**
* Compares the objects of two AbstractStringBuilder implementations lexicographically.
*
* @since 11
*/
int compareTo(AbstractStringBuilder another) {
if (this == another) {
return 0;
}
byte[] val1 = value;
byte[] val2 = another.value;
int count1 = this.count;
int count2 = another.count;
if (coder == another.coder) {
return isLatin1() ? StringLatin1.compareTo(val1, val2, count1, count2)
: StringUTF16.compareTo(val1, val2, count1, count2);
}
return isLatin1() ? StringLatin1.compareToUTF16(val1, val2, count1, count2)
: StringUTF16.compareToLatin1(val1, val2, count1, count2);
}
/**
* Returns the length (character count).
*
* @return the length of the sequence of characters currently
* represented by this object
*/
@Override
public int length() {
return count;
}
/**
* Returns the current capacity. The capacity is the number of characters
* that can be stored (including already written characters), beyond which
* an allocation will occur.
*
* @return the current capacity
*/
public int capacity() {
return value.length >> coder;
}
/**
* Ensures that the capacity is at least equal to the specified minimum.
* If the current capacity is less than the argument, then a new internal
* array is allocated with greater capacity. The new capacity is the
* larger of:
* <ul>
* <li>The {@code minimumCapacity} argument.
* <li>Twice the old capacity, plus {@code 2}.
* </ul>
* If the {@code minimumCapacity} argument is nonpositive, this
* method takes no action and simply returns.
* Note that subsequent operations on this object can reduce the
* actual capacity below that requested here.
*
* @param minimumCapacity the minimum desired capacity.
*/
public void ensureCapacity(int minimumCapacity) {
if (minimumCapacity > 0) {
ensureCapacityInternal(minimumCapacity);
}
}
/**
* For positive values of {@code minimumCapacity}, this method
* behaves like {@code ensureCapacity}, however it is never
* synchronized.
* If {@code minimumCapacity} is non positive due to numeric
* overflow, this method throws {@code OutOfMemoryError}.
*/
private void ensureCapacityInternal(int minimumCapacity) {
// overflow-conscious code
int oldCapacity = value.length >> coder;
if (minimumCapacity - oldCapacity > 0) {
value = Arrays.copyOf(value,
newCapacity(minimumCapacity) << coder);
}
}
/**
* Returns a capacity at least as large as the given minimum capacity.
* Returns the current capacity increased by the current length + 2 if
* that suffices.
* Will not return a capacity greater than
* {@code (SOFT_MAX_ARRAY_LENGTH >> coder)}
* unless the given minimum capacity is greater than that.
*
* @param minCapacity the desired minimum capacity
* @throws OutOfMemoryError if minCapacity is less than zero or
* greater than (Integer.MAX_VALUE >> coder)
*/
private int newCapacity(int minCapacity) {
int oldLength = value.length;
int newLength = minCapacity << coder;
int growth = newLength - oldLength;
int length = ArraysSupport.newLength(oldLength, growth, oldLength + (2 << coder));
if (length == Integer.MAX_VALUE) {
throw new OutOfMemoryError("Required length exceeds implementation limit");
}
return length >> coder;
}
/**
* If the coder is "isLatin1", this inflates the internal 8-bit storage
* to 16-bit <hi=0, low> pair storage.
*/
private void inflate() {
if (!isLatin1()) {
return;
}
byte[] buf = StringUTF16.newBytesFor(value.length);
StringLatin1.inflate(value, 0, buf, 0, count);
this.value = buf;
this.coder = UTF16;
}
/**
* Attempts to reduce storage used for the character sequence.
* If the buffer is larger than necessary to hold its current sequence of
* characters, then it may be resized to become more space efficient.
* Calling this method may, but is not required to, affect the value
* returned by a subsequent call to the {@link #capacity()} method.
*/
public void trimToSize() {
int length = count << coder;
if (length < value.length) {
value = Arrays.copyOf(value, length);
}
}
/**
* Sets the length of the character sequence.
* The sequence is changed to a new character sequence
* whose length is specified by the argument. For every nonnegative
* index <i>k</i> less than {@code newLength}, the character at
* index <i>k</i> in the new character sequence is the same as the
* character at index <i>k</i> in the old sequence if <i>k</i> is less
* than the length of the old character sequence; otherwise, it is the
* null character {@code '\u005Cu0000'}.
*
* In other words, if the {@code newLength} argument is less than
* the current length, the length is changed to the specified length.
* <p>
* If the {@code newLength} argument is greater than or equal
* to the current length, sufficient null characters
* ({@code '\u005Cu0000'}) are appended so that
* length becomes the {@code newLength} argument.
* <p>
* The {@code newLength} argument must be greater than or equal
* to {@code 0}.
*
* @param newLength the new length
* @throws IndexOutOfBoundsException if the
* {@code newLength} argument is negative.
*/
public void setLength(int newLength) {
if (newLength < 0) {
throw new StringIndexOutOfBoundsException(newLength);
}
ensureCapacityInternal(newLength);
if (count < newLength) {
if (isLatin1()) {
StringLatin1.fillNull(value, count, newLength);
} else {
StringUTF16.fillNull(value, count, newLength);
}
} else if (count > newLength) {
maybeLatin1 = true;
}
count = newLength;
}
/**
* Returns the {@code char} value in this sequence at the specified index.
* The first {@code char} value is at index {@code 0}, the next at index
* {@code 1}, and so on, as in array indexing.
* <p>
* The index argument must be greater than or equal to
* {@code 0}, and less than the length of this sequence.
*
* <p>If the {@code char} value specified by the index is a
* <a href="Character.html#unicode">surrogate</a>, the surrogate
* value is returned.
*
* @param index the index of the desired {@code char} value.
* @return the {@code char} value at the specified index.
* @throws IndexOutOfBoundsException if {@code index} is
* negative or greater than or equal to {@code length()}.
*/
@Override
public char charAt(int index) {
checkIndex(index, count);
if (isLatin1()) {
return (char)(value[index] & 0xff);
}
return StringUTF16.getChar(value, index);
}
/**
* Returns the character (Unicode code point) at the specified
* index. The index refers to {@code char} values
* (Unicode code units) and ranges from {@code 0} to
* {@link #length()}{@code - 1}.
*
* <p> If the {@code char} value specified at the given index
* is in the high-surrogate range, the following index is less
* than the length of this sequence, and the
* {@code char} value at the following index is in the
* low-surrogate range, then the supplementary code point
* corresponding to this surrogate pair is returned. Otherwise,
* the {@code char} value at the given index is returned.
*
* @param index the index to the {@code char} values
* @return the code point value of the character at the
* {@code index}
* @throws IndexOutOfBoundsException if the {@code index}
* argument is negative or not less than the length of this
* sequence.
*/
public int codePointAt(int index) {
int count = this.count;
byte[] value = this.value;
checkIndex(index, count);
if (isLatin1()) {
return value[index] & 0xff;
}
return StringUTF16.codePointAtSB(value, index, count);
}
/**
* Returns the character (Unicode code point) before the specified
* index. The index refers to {@code char} values
* (Unicode code units) and ranges from {@code 1} to {@link
* #length()}.
*
* <p> If the {@code char} value at {@code (index - 1)}
* is in the low-surrogate range, {@code (index - 2)} is not
* negative, and the {@code char} value at {@code (index -
* 2)} is in the high-surrogate range, then the
* supplementary code point value of the surrogate pair is
* returned. If the {@code char} value at {@code index -
* 1} is an unpaired low-surrogate or a high-surrogate, the
* surrogate value is returned.
*
* @param index the index following the code point that should be returned
* @return the Unicode code point value before the given index.
* @throws IndexOutOfBoundsException if the {@code index}
* argument is less than 1 or greater than the length
* of this sequence.
*/
public int codePointBefore(int index) {
int i = index - 1;
checkIndex(i, count);
if (isLatin1()) {
return value[i] & 0xff;
}
return StringUTF16.codePointBeforeSB(value, index);
}
/**
* Returns the number of Unicode code points in the specified text
* range of this sequence. The text range begins at the specified
* {@code beginIndex} and extends to the {@code char} at
* index {@code endIndex - 1}. Thus the length (in
* {@code char}s) of the text range is
* {@code endIndex-beginIndex}. Unpaired surrogates within
* this sequence count as one code point each.
*
* @param beginIndex the index to the first {@code char} of
* the text range.
* @param endIndex the index after the last {@code char} of
* the text range.
* @return the number of Unicode code points in the specified text
* range
* @throws IndexOutOfBoundsException if the
* {@code beginIndex} is negative, or {@code endIndex}
* is larger than the length of this sequence, or
* {@code beginIndex} is larger than {@code endIndex}.
*/
public int codePointCount(int beginIndex, int endIndex) {
Preconditions.checkFromToIndex(beginIndex, endIndex, length(), null);
if (isLatin1()) {
return endIndex - beginIndex;
}
return StringUTF16.codePointCountSB(value, beginIndex, endIndex);
}
/**
* Returns the index within this sequence that is offset from the
* given {@code index} by {@code codePointOffset} code
* points. Unpaired surrogates within the text range given by
* {@code index} and {@code codePointOffset} count as
* one code point each.
*
* @param index the index to be offset
* @param codePointOffset the offset in code points
* @return the index within this sequence
* @throws IndexOutOfBoundsException if {@code index}
* is negative or larger than the length of this sequence,
* or if {@code codePointOffset} is positive and the subsequence
* starting with {@code index} has fewer than
* {@code codePointOffset} code points,
* or if {@code codePointOffset} is negative and the subsequence
* before {@code index} has fewer than the absolute value of
* {@code codePointOffset} code points.
*/
public int offsetByCodePoints(int index, int codePointOffset) {
if (index < 0 || index > count) {
throw new IndexOutOfBoundsException();
}
return Character.offsetByCodePoints(this,
index, codePointOffset);
}
/**
* Characters are copied from this sequence into the
* destination character array {@code dst}. The first character to
* be copied is at index {@code srcBegin}; the last character to
* be copied is at index {@code srcEnd-1}. The total number of
* characters to be copied is {@code srcEnd-srcBegin}. The
* characters are copied into the subarray of {@code dst} starting
* at index {@code dstBegin} and ending at index:
* <pre>{@code
* dstbegin + (srcEnd-srcBegin) - 1
* }</pre>
*
* @param srcBegin start copying at this offset.
* @param srcEnd stop copying at this offset.
* @param dst the array to copy the data into.
* @param dstBegin offset into {@code dst}.
* @throws IndexOutOfBoundsException if any of the following is true:
* <ul>
* <li>{@code srcBegin} is negative
* <li>{@code dstBegin} is negative
* <li>the {@code srcBegin} argument is greater than
* the {@code srcEnd} argument.
* <li>{@code srcEnd} is greater than
* {@code this.length()}.
* <li>{@code dstBegin+srcEnd-srcBegin} is greater than
* {@code dst.length}
* </ul>
*/
public void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)
{
Preconditions.checkFromToIndex(srcBegin, srcEnd, count, Preconditions.SIOOBE_FORMATTER); // compatible to old version
int n = srcEnd - srcBegin;
Preconditions.checkFromToIndex(dstBegin, dstBegin + n, dst.length, Preconditions.IOOBE_FORMATTER);
if (isLatin1()) {
StringLatin1.getChars(value, srcBegin, srcEnd, dst, dstBegin);
} else {
StringUTF16.getChars(value, srcBegin, srcEnd, dst, dstBegin);
}
}
/**
* The character at the specified index is set to {@code ch}. This
* sequence is altered to represent a new character sequence that is
* identical to the old character sequence, except that it contains the
* character {@code ch} at position {@code index}.
* <p>
* The index argument must be greater than or equal to
* {@code 0}, and less than the length of this sequence.
*
* @param index the index of the character to modify.
* @param ch the new character.
* @throws IndexOutOfBoundsException if {@code index} is
* negative or greater than or equal to {@code length()}.
*/
public void setCharAt(int index, char ch) {
checkIndex(index, count);
if (isLatin1() && StringLatin1.canEncode(ch)) {
value[index] = (byte)ch;
} else {
if (isLatin1()) {
inflate();
}
StringUTF16.putCharSB(value, index, ch);
maybeLatin1 = true;
}
}
/**
* Appends the string representation of the {@code Object} argument.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(Object)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param obj an {@code Object}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(Object obj) {
return append(String.valueOf(obj));
}
/**
* Appends the specified string to this character sequence.
* <p>
* The characters of the {@code String} argument are appended, in
* order, increasing the length of this sequence by the length of the
* argument. If {@code str} is {@code null}, then the four
* characters {@code "null"} are appended.
* <p>
* Let <i>n</i> be the length of this character sequence just prior to
* execution of the {@code append} method. Then the character at
* index <i>k</i> in the new character sequence is equal to the character
* at index <i>k</i> in the old character sequence, if <i>k</i> is less
* than <i>n</i>; otherwise, it is equal to the character at index
* <i>k-n</i> in the argument {@code str}.
*
* @param str a string.
* @return a reference to this object.
*/
public AbstractStringBuilder append(String str) {
if (str == null) {
return appendNull();
}
int len = str.length();
ensureCapacityInternal(count + len);
putStringAt(count, str);
count += len;
return this;
}
/**
* Appends the specified {@code StringBuffer} to this sequence.
*
* @param sb the {@code StringBuffer} to append.
* @return a reference to this object.
*/
public AbstractStringBuilder append(StringBuffer sb) {
return this.append((AbstractStringBuilder)sb);
}
/**
* @since 1.8
*/
AbstractStringBuilder append(AbstractStringBuilder asb) {
if (asb == null) {
return appendNull();
}
int len = asb.length();
ensureCapacityInternal(count + len);
inflateIfNeededFor(asb);
asb.getBytes(value, count, coder);
count += len;
maybeLatin1 |= asb.maybeLatin1;
return this;
}
// Documentation in subclasses because of synchro difference
@Override
public AbstractStringBuilder append(CharSequence s) {
if (s == null) {
return appendNull();
}
if (s instanceof String) {
return this.append((String)s);
}
if (s instanceof AbstractStringBuilder) {
return this.append((AbstractStringBuilder)s);
}
return this.append(s, 0, s.length());
}
private AbstractStringBuilder appendNull() {
ensureCapacityInternal(count + 4);
int count = this.count;
byte[] val = this.value;
if (isLatin1()) {
val[count++] = 'n';
val[count++] = 'u';
val[count++] = 'l';
val[count++] = 'l';
} else {
count = StringUTF16.putCharsAt(val, count, 'n', 'u', 'l', 'l');
}
this.count = count;
return this;
}
/**
* Appends a subsequence of the specified {@code CharSequence} to this
* sequence.
* <p>
* Characters of the argument {@code s}, starting at
* index {@code start}, are appended, in order, to the contents of
* this sequence up to the (exclusive) index {@code end}. The length
* of this sequence is increased by the value of {@code end - start}.
* <p>
* Let <i>n</i> be the length of this character sequence just prior to
* execution of the {@code append} method. Then the character at
* index <i>k</i> in this character sequence becomes equal to the
* character at index <i>k</i> in this sequence, if <i>k</i> is less than
* <i>n</i>; otherwise, it is equal to the character at index
* <i>k+start-n</i> in the argument {@code s}.
* <p>
* If {@code s} is {@code null}, then this method appends
* characters as if the s parameter was a sequence containing the four
* characters {@code "null"}.
* <p>
* The contents are unspecified if the {@code CharSequence}
* is modified during the method call or an exception is thrown
* when accessing the {@code CharSequence}.
*
* @param s the sequence to append.
* @param start the starting index of the subsequence to be appended.
* @param end the end index of the subsequence to be appended.
* @return a reference to this object.
* @throws IndexOutOfBoundsException if
* {@code start} is negative, or
* {@code start} is greater than {@code end} or
* {@code end} is greater than {@code s.length()}
*/
@Override
public AbstractStringBuilder append(CharSequence s, int start, int end) {
if (s == null) {
s = "null";
}
Preconditions.checkFromToIndex(start, end, s.length(), Preconditions.IOOBE_FORMATTER);
int len = end - start;
ensureCapacityInternal(count + len);
if (s instanceof String) {
appendChars((String)s, start, end);
} else {
appendChars(s, start, end);
}
return this;
}
/**
* Appends the string representation of the {@code char} array
* argument to this sequence.
* <p>
* The characters of the array argument are appended, in order, to
* the contents of this sequence. The length of this sequence
* increases by the length of the argument.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(char[])},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param str the characters to be appended.
* @return a reference to this object.
*/
public AbstractStringBuilder append(char[] str) {
int len = str.length;
ensureCapacityInternal(count + len);
appendChars(str, 0, len);
return this;
}
/**
* Appends the string representation of a subarray of the
* {@code char} array argument to this sequence.
* <p>
* Characters of the {@code char} array {@code str}, starting at
* index {@code offset}, are appended, in order, to the contents
* of this sequence. The length of this sequence increases
* by the value of {@code len}.
* <p>
* The overall effect is exactly as if the arguments were converted
* to a string by the method {@link String#valueOf(char[],int,int)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param str the characters to be appended.
* @param offset the index of the first {@code char} to append.
* @param len the number of {@code char}s to append.
* @return a reference to this object.
* @throws IndexOutOfBoundsException
* if {@code offset < 0} or {@code len < 0}
* or {@code offset+len > str.length}
*/
public AbstractStringBuilder append(char[] str, int offset, int len) {
int end = offset + len;
Preconditions.checkFromToIndex(offset, end, str.length, Preconditions.IOOBE_FORMATTER);
ensureCapacityInternal(count + len);
appendChars(str, offset, end);
return this;
}
/**
* Appends the string representation of the {@code boolean}
* argument to the sequence.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(boolean)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param b a {@code boolean}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(boolean b) {
ensureCapacityInternal(count + (b ? 4 : 5));
int count = this.count;
byte[] val = this.value;
if (isLatin1()) {
if (b) {
val[count++] = 't';
val[count++] = 'r';
val[count++] = 'u';
val[count++] = 'e';
} else {
val[count++] = 'f';
val[count++] = 'a';
val[count++] = 'l';
val[count++] = 's';
val[count++] = 'e';
}
} else {
if (b) {
count = StringUTF16.putCharsAt(val, count, 't', 'r', 'u', 'e');
} else {
count = StringUTF16.putCharsAt(val, count, 'f', 'a', 'l', 's', 'e');
}
}
this.count = count;
return this;
}
/**
* Appends the string representation of the {@code char}
* argument to this sequence.
* <p>
* The argument is appended to the contents of this sequence.
* The length of this sequence increases by {@code 1}.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(char)},
* and the character in that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param c a {@code char}.
* @return a reference to this object.
*/
@Override
public AbstractStringBuilder append(char c) {
ensureCapacityInternal(count + 1);
if (isLatin1() && StringLatin1.canEncode(c)) {
value[count++] = (byte)c;
} else {
if (isLatin1()) {
inflate();
}
StringUTF16.putCharSB(value, count++, c);
}
return this;
}
/**
* Appends the string representation of the {@code int}
* argument to this sequence.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(int)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param i an {@code int}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(int i) {
int count = this.count;
int spaceNeeded = count + Integer.stringSize(i);
ensureCapacityInternal(spaceNeeded);
if (isLatin1()) {
StringLatin1.getChars(i, spaceNeeded, value);
} else {
StringUTF16.getChars(i, count, spaceNeeded, value);
}
this.count = spaceNeeded;
return this;
}
/**
* Appends the string representation of the {@code long}
* argument to this sequence.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(long)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param l a {@code long}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(long l) {
int count = this.count;
int spaceNeeded = count + Long.stringSize(l);
ensureCapacityInternal(spaceNeeded);
if (isLatin1()) {
StringLatin1.getChars(l, spaceNeeded, value);
} else {
StringUTF16.getChars(l, count, spaceNeeded, value);
}
this.count = spaceNeeded;
return this;
}
/**
* Appends the string representation of the {@code float}
* argument to this sequence.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(float)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param f a {@code float}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(float f) {
try {
FloatToDecimal.appendTo(f, this);
} catch (IOException e) {
throw new AssertionError(e);
}
return this;
}
/**
* Appends the string representation of the {@code double}
* argument to this sequence.
* <p>
* The overall effect is exactly as if the argument were converted
* to a string by the method {@link String#valueOf(double)},
* and the characters of that string were then
* {@link #append(String) appended} to this character sequence.
*
* @param d a {@code double}.
* @return a reference to this object.
*/
public AbstractStringBuilder append(double d) {
try {
DoubleToDecimal.appendTo(d, this);
} catch (IOException e) {
throw new AssertionError(e);
}
return this;
}
/**
* Removes the characters in a substring of this sequence.
* The substring begins at the specified {@code start} and extends to
* the character at index {@code end - 1} or to the end of the
* sequence if no such character exists. If
* {@code start} is equal to {@code end}, no changes are made.
*
* @param start The beginning index, inclusive.
* @param end The ending index, exclusive.
* @return This object.
* @throws StringIndexOutOfBoundsException if {@code start}
* is negative, greater than {@code length()}, or
* greater than {@code end}.
*/
public AbstractStringBuilder delete(int start, int end) {
int count = this.count;
if (end > count) {
end = count;
}
Preconditions.checkFromToIndex(start, end, count, Preconditions.SIOOBE_FORMATTER);
int len = end - start;
if (len > 0) {
shift(end, -len);
this.count = count - len;
maybeLatin1 = true;
}
return this;
}
/**
* Appends the string representation of the {@code codePoint}
* argument to this sequence.
*
* <p> The argument is appended to the contents of this sequence.
* The length of this sequence increases by
* {@link Character#charCount(int) Character.charCount(codePoint)}.
*
* <p> The overall effect is exactly as if the argument were
* converted to a {@code char} array by the method
* {@link Character#toChars(int)} and the character in that array
* were then {@link #append(char[]) appended} to this character
* sequence.
*
* @param codePoint a Unicode code point
* @return a reference to this object.
* @throws IllegalArgumentException if the specified
* {@code codePoint} isn't a valid Unicode code point
*/
public AbstractStringBuilder appendCodePoint(int codePoint) {
if (Character.isBmpCodePoint(codePoint)) {
return append((char)codePoint);
}
return append(Character.toChars(codePoint));
}
/**
* Removes the {@code char} at the specified position in this
* sequence. This sequence is shortened by one {@code char}.
*
* <p>Note: If the character at the given index is a supplementary
* character, this method does not remove the entire character. If
* correct handling of supplementary characters is required,
* determine the number of {@code char}s to remove by calling
* {@code Character.charCount(thisSequence.codePointAt(index))},
* where {@code thisSequence} is this sequence.
*
* @param index Index of {@code char} to remove
* @return This object.
* @throws StringIndexOutOfBoundsException if the {@code index}
* is negative or greater than or equal to
* {@code length()}.
*/
public AbstractStringBuilder deleteCharAt(int index) {
checkIndex(index, count);
shift(index + 1, -1);
count--;
maybeLatin1 = true;
return this;
}
/**
* Replaces the characters in a substring of this sequence
* with characters in the specified {@code String}. The substring