515 lines
16 KiB
Java
515 lines
16 KiB
Java
![]() |
/*
|
||
|
* Copyright (C) 2014 The Android Open Source Project
|
||
|
* Copyright (c) 2003, 2018, 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 dalvik.annotation.optimization.NeverInline;
|
||
|
import jdk.internal.HotSpotIntrinsicCandidate;
|
||
|
|
||
|
/**
|
||
|
* A mutable sequence of characters. This class provides an API compatible
|
||
|
* with {@code StringBuffer}, but with no guarantee of synchronization.
|
||
|
* This class is designed for use as a drop-in replacement for
|
||
|
* {@code StringBuffer} in places where the string buffer was being
|
||
|
* used by a single thread (as is generally the case). Where possible,
|
||
|
* it is recommended that this class be used in preference to
|
||
|
* {@code StringBuffer} as it will be faster under most implementations.
|
||
|
*
|
||
|
* <p>The principal operations on a {@code StringBuilder} are the
|
||
|
* {@code append} and {@code insert} methods, which are
|
||
|
* overloaded so as to accept data of any type. Each effectively
|
||
|
* converts a given datum to a string and then appends or inserts the
|
||
|
* characters of that string to the string builder. The
|
||
|
* {@code append} method always adds these characters at the end
|
||
|
* of the builder; the {@code insert} method adds the characters at
|
||
|
* a specified point.
|
||
|
* <p>
|
||
|
* For example, if {@code z} refers to a string builder object
|
||
|
* whose current contents are "{@code start}", then
|
||
|
* the method call {@code z.append("le")} would cause the string
|
||
|
* builder to contain "{@code startle}", whereas
|
||
|
* {@code z.insert(4, "le")} would alter the string builder to
|
||
|
* contain "{@code starlet}".
|
||
|
* <p>
|
||
|
* In general, if sb refers to an instance of a {@code StringBuilder},
|
||
|
* then {@code sb.append(x)} has the same effect as
|
||
|
* {@code sb.insert(sb.length(), x)}.
|
||
|
* <p>
|
||
|
* Every string builder has a capacity. As long as the length of the
|
||
|
* character sequence contained in the string builder does not exceed
|
||
|
* the capacity, it is not necessary to allocate a new internal
|
||
|
* buffer. If the internal buffer overflows, it is automatically made larger.
|
||
|
*
|
||
|
* <p>Instances of {@code StringBuilder} are not safe for
|
||
|
* use by multiple threads. If such synchronization is required then it is
|
||
|
* recommended that {@link java.lang.StringBuffer} be used.
|
||
|
*
|
||
|
* <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.
|
||
|
*
|
||
|
* @apiNote
|
||
|
* {@code StringBuilder} implements {@code Comparable} but does not override
|
||
|
* {@link Object#equals equals}. Thus, the natural ordering of {@code StringBuilder}
|
||
|
* is inconsistent with equals. Care should be exercised if {@code StringBuilder}
|
||
|
* objects are used as keys in a {@code SortedMap} or elements in a {@code SortedSet}.
|
||
|
* See {@link Comparable}, {@link java.util.SortedMap SortedMap}, or
|
||
|
* {@link java.util.SortedSet SortedSet} for more information.
|
||
|
*
|
||
|
* @author Michael McCloskey
|
||
|
* @see java.lang.StringBuffer
|
||
|
* @see java.lang.String
|
||
|
* @since 1.5
|
||
|
*/
|
||
|
public final class StringBuilder
|
||
|
extends AbstractStringBuilder
|
||
|
implements java.io.Serializable, Comparable<StringBuilder>, CharSequence
|
||
|
{
|
||
|
|
||
|
/** use serialVersionUID for interoperability */
|
||
|
static final long serialVersionUID = 4383685877147921099L;
|
||
|
|
||
|
// Android-changed: Add @NeverInline for InstructionSimplifier optimization. See b/19575890.
|
||
|
/**
|
||
|
* Constructs a string builder with no characters in it and an
|
||
|
* initial capacity of 16 characters.
|
||
|
*/
|
||
|
@NeverInline
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
public StringBuilder() {
|
||
|
super(16);
|
||
|
}
|
||
|
|
||
|
// Android-changed: Add @NeverInline for InstructionSimplifier optimization. See b/19575890.
|
||
|
/**
|
||
|
* Constructs a string builder with no characters in it and an
|
||
|
* initial capacity specified by the {@code capacity} argument.
|
||
|
*
|
||
|
* @param capacity the initial capacity.
|
||
|
* @throws NegativeArraySizeException if the {@code capacity}
|
||
|
* argument is less than {@code 0}.
|
||
|
*/
|
||
|
@NeverInline
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
public StringBuilder(int capacity) {
|
||
|
super(capacity);
|
||
|
}
|
||
|
|
||
|
// Android-changed: Add @NeverInline for InstructionSimplifier optimization. See b/19575890.
|
||
|
/**
|
||
|
* Constructs a string builder initialized to the contents of the
|
||
|
* specified string. The initial capacity of the string builder is
|
||
|
* {@code 16} plus the length of the string argument.
|
||
|
*
|
||
|
* @param str the initial contents of the buffer.
|
||
|
*/
|
||
|
@NeverInline
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
public StringBuilder(String str) {
|
||
|
super(str.length() + 16);
|
||
|
append(str);
|
||
|
}
|
||
|
|
||
|
// Android-changed: Add @NeverInline for InstructionSimplifier optimization. See b/19575890.
|
||
|
/**
|
||
|
* Constructs a string builder 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.
|
||
|
*
|
||
|
* @param seq the sequence to copy.
|
||
|
*/
|
||
|
@NeverInline
|
||
|
public StringBuilder(CharSequence seq) {
|
||
|
this(seq.length() + 16);
|
||
|
append(seq);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Compares two {@code StringBuilder} instances lexicographically. This method
|
||
|
* follows the same rules for lexicographical comparison as defined in the
|
||
|
* {@linkplain java.lang.CharSequence#compare(java.lang.CharSequence,
|
||
|
* java.lang.CharSequence) CharSequence.compare(this, another)} method.
|
||
|
*
|
||
|
* <p>
|
||
|
* For finer-grained, locale-sensitive String comparison, refer to
|
||
|
* {@link java.text.Collator}.
|
||
|
*
|
||
|
* @param another the {@code StringBuilder} to be compared with
|
||
|
*
|
||
|
* @return the value {@code 0} if this {@code StringBuilder} contains the same
|
||
|
* character sequence as that of the argument {@code StringBuilder}; a negative integer
|
||
|
* if this {@code StringBuilder} is lexicographically less than the
|
||
|
* {@code StringBuilder} argument; or a positive integer if this {@code StringBuilder}
|
||
|
* is lexicographically greater than the {@code StringBuilder} argument.
|
||
|
*
|
||
|
* @since 11
|
||
|
*/
|
||
|
@Override
|
||
|
public int compareTo(StringBuilder another) {
|
||
|
return super.compareTo(another);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(Object obj) {
|
||
|
return append(String.valueOf(obj));
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
@NeverInline
|
||
|
public StringBuilder append(String str) {
|
||
|
super.append(str);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Appends the specified {@code StringBuffer} to this sequence.
|
||
|
* <p>
|
||
|
* The characters of the {@code StringBuffer} argument are appended,
|
||
|
* in order, to this sequence, increasing the
|
||
|
* length of this sequence by the length of the argument.
|
||
|
* If {@code sb} is {@code null}, then the four characters
|
||
|
* {@code "null"} are appended to this sequence.
|
||
|
* <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 sb}.
|
||
|
*
|
||
|
* @param sb the {@code StringBuffer} to append.
|
||
|
* @return a reference to this object.
|
||
|
*/
|
||
|
public StringBuilder append(StringBuffer sb) {
|
||
|
super.append(sb);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(CharSequence s) {
|
||
|
super.append(s);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder append(CharSequence s, int start, int end) {
|
||
|
super.append(s, start, end);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(char[] str) {
|
||
|
super.append(str);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder append(char[] str, int offset, int len) {
|
||
|
super.append(str, offset, len);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(boolean b) {
|
||
|
super.append(b);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
@NeverInline
|
||
|
public StringBuilder append(char c) {
|
||
|
super.append(c);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
@NeverInline
|
||
|
public StringBuilder append(int i) {
|
||
|
super.append(i);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(long lng) {
|
||
|
super.append(lng);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(float f) {
|
||
|
super.append(f);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@NeverInline
|
||
|
public StringBuilder append(double d) {
|
||
|
super.append(d);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @since 1.5
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder appendCodePoint(int codePoint) {
|
||
|
super.appendCodePoint(codePoint);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder delete(int start, int end) {
|
||
|
super.delete(start, end);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder deleteCharAt(int index) {
|
||
|
super.deleteCharAt(index);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder replace(int start, int end, String str) {
|
||
|
super.replace(start, end, str);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int index, char[] str, int offset,
|
||
|
int len)
|
||
|
{
|
||
|
super.insert(index, str, offset, len);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, Object obj) {
|
||
|
super.insert(offset, obj);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, String str) {
|
||
|
super.insert(offset, str);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, char[] str) {
|
||
|
super.insert(offset, str);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int dstOffset, CharSequence s) {
|
||
|
super.insert(dstOffset, s);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int dstOffset, CharSequence s,
|
||
|
int start, int end)
|
||
|
{
|
||
|
super.insert(dstOffset, s, start, end);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, boolean b) {
|
||
|
super.insert(offset, b);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, char c) {
|
||
|
super.insert(offset, c);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, int i) {
|
||
|
super.insert(offset, i);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, long l) {
|
||
|
super.insert(offset, l);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, float f) {
|
||
|
super.insert(offset, f);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @throws StringIndexOutOfBoundsException {@inheritDoc}
|
||
|
*/
|
||
|
@Override
|
||
|
public StringBuilder insert(int offset, double d) {
|
||
|
super.insert(offset, d);
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public int indexOf(String str) {
|
||
|
return super.indexOf(str);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public int indexOf(String str, int fromIndex) {
|
||
|
return super.indexOf(str, fromIndex);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public int lastIndexOf(String str) {
|
||
|
return super.lastIndexOf(str);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public int lastIndexOf(String str, int fromIndex) {
|
||
|
return super.lastIndexOf(str, fromIndex);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public StringBuilder reverse() {
|
||
|
super.reverse();
|
||
|
return this;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
@HotSpotIntrinsicCandidate
|
||
|
@NeverInline
|
||
|
public String toString() {
|
||
|
// BEGIN Android-added: Return a constant "" for an empty buffer to keep historic behavior.
|
||
|
if (count == 0) {
|
||
|
return "";
|
||
|
}
|
||
|
// END Android-added: Return a constant "" for an empty buffer to keep historic behavior.
|
||
|
// Create a copy, don't share the array
|
||
|
return isLatin1() ? StringLatin1.newString(value, 0, count)
|
||
|
: StringUTF16.newString(value, 0, count);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Save the state of the {@code StringBuilder} instance to a stream
|
||
|
* (that is, serialize it).
|
||
|
*
|
||
|
* @serialData the number of characters currently stored in the string
|
||
|
* builder ({@code int}), followed by the characters in the
|
||
|
* string builder ({@code char[]}). The length of the
|
||
|
* {@code char} array may be greater than the number of
|
||
|
* characters currently stored in the string builder, in which
|
||
|
* case extra characters are ignored.
|
||
|
*/
|
||
|
private void writeObject(java.io.ObjectOutputStream s)
|
||
|
throws java.io.IOException {
|
||
|
s.defaultWriteObject();
|
||
|
s.writeInt(count);
|
||
|
char[] val = new char[capacity()];
|
||
|
if (isLatin1()) {
|
||
|
StringLatin1.getChars(value, 0, count, val, 0);
|
||
|
} else {
|
||
|
StringUTF16.getChars(value, 0, count, val, 0);
|
||
|
}
|
||
|
s.writeObject(val);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* readObject is called to restore the state of the StringBuffer from
|
||
|
* a stream.
|
||
|
*/
|
||
|
private void readObject(java.io.ObjectInputStream s)
|
||
|
throws java.io.IOException, ClassNotFoundException {
|
||
|
s.defaultReadObject();
|
||
|
count = s.readInt();
|
||
|
char[] val = (char[]) s.readObject();
|
||
|
initBytes(val, 0, val.length);
|
||
|
}
|
||
|
|
||
|
}
|