| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * Copyright (c) 1994, 2010, 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 java.io.ObjectStreamField; |
| import java.io.UnsupportedEncodingException; |
| import java.lang.ArrayIndexOutOfBoundsException; |
| import java.nio.charset.Charset; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Comparator; |
| import java.util.Formatter; |
| import java.util.Locale; |
| import java.util.Objects; |
| import java.util.StringJoiner; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| import java.util.regex.PatternSyntaxException; |
| |
| import libcore.util.CharsetUtils; |
| import libcore.util.EmptyArray; |
| |
| /** |
| * The {@code String} class represents character strings. All |
| * string literals in Java programs, such as {@code "abc"}, are |
| * implemented as instances of this class. |
| * <p> |
| * Strings are constant; their values cannot be changed after they |
| * are created. String buffers support mutable strings. |
| * Because String objects are immutable they can be shared. For example: |
| * <blockquote><pre> |
| * String str = "abc"; |
| * </pre></blockquote><p> |
| * is equivalent to: |
| * <blockquote><pre> |
| * char data[] = {'a', 'b', 'c'}; |
| * String str = new String(data); |
| * </pre></blockquote><p> |
| * Here are some more examples of how strings can be used: |
| * <blockquote><pre> |
| * System.out.println("abc"); |
| * String cde = "cde"; |
| * System.out.println("abc" + cde); |
| * String c = "abc".substring(2,3); |
| * String d = cde.substring(1, 2); |
| * </pre></blockquote> |
| * <p> |
| * The class {@code String} includes methods for examining |
| * individual characters of the sequence, for comparing strings, for |
| * searching strings, for extracting substrings, and for creating a |
| * copy of a string with all characters translated to uppercase or to |
| * lowercase. Case mapping is based on the Unicode Standard version |
| * specified by the {@link java.lang.Character Character} class. |
| * <p> |
| * The Java language provides special support for the string |
| * concatenation operator ( + ), and for conversion of |
| * other objects to strings. String concatenation is implemented |
| * through the {@code StringBuilder}(or {@code StringBuffer}) |
| * class and its {@code append} method. |
| * String conversions are implemented through the method |
| * {@code toString}, defined by {@code Object} and |
| * inherited by all classes in Java. For additional information on |
| * string concatenation and conversion, see Gosling, Joy, and Steele, |
| * <i>The Java Language Specification</i>. |
| * |
| * <p> Unless otherwise noted, passing a <tt>null</tt> argument to a constructor |
| * or method in this class will cause a {@link NullPointerException} to be |
| * thrown. |
| * |
| * <p>A {@code String} represents a string in the UTF-16 format |
| * in which <em>supplementary characters</em> are represented by <em>surrogate |
| * pairs</em> (see the section <a href="Character.html#unicode">Unicode |
| * Character Representations</a> in the {@code Character} class for |
| * more information). |
| * Index values refer to {@code char} code units, so a supplementary |
| * character uses two positions in a {@code String}. |
| * <p>The {@code String} class provides methods for dealing with |
| * Unicode code points (i.e., characters), in addition to those for |
| * dealing with Unicode code units (i.e., {@code char} values). |
| * |
| * @author Lee Boynton |
| * @author Arthur van Hoff |
| * @author Martin Buchholz |
| * @author Ulf Zibis |
| * @see java.lang.Object#toString() |
| * @see java.lang.StringBuffer |
| * @see java.lang.StringBuilder |
| * @see java.nio.charset.Charset |
| * @since JDK1.0 |
| */ |
| |
| public final class String |
| implements java.io.Serializable, Comparable<String>, CharSequence { |
| |
| // dThe associated character storage is managed by the runtime. We only |
| // keep track of the length here. |
| // |
| // private final char value[]; |
| private final int count; |
| |
| /** Cache the hash code for the string */ |
| private int hash; // Default to 0 |
| |
| /** use serialVersionUID from JDK 1.0.2 for interoperability */ |
| private static final long serialVersionUID = -6849794470754667710L; |
| |
| /** |
| * Class String is special cased within the Serialization Stream Protocol. |
| * |
| * A String instance is written into an ObjectOutputStream according to |
| * <a href="{@docRoot}/../platform/serialization/spec/output.html"> |
| * Object Serialization Specification, Section 6.2, "Stream Elements"</a> |
| */ |
| private static final ObjectStreamField[] serialPersistentFields = |
| new ObjectStreamField[0]; |
| |
| /** |
| * Initializes a newly created {@code String} object so that it represents |
| * an empty character sequence. Note that use of this constructor is |
| * unnecessary since Strings are immutable. |
| */ |
| public String() { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Initializes a newly created {@code String} object so that it represents |
| * the same sequence of characters as the argument; in other words, the |
| * newly created string is a copy of the argument string. Unless an |
| * explicit copy of {@code original} is needed, use of this constructor is |
| * unnecessary since Strings are immutable. |
| * |
| * @param original |
| * A {@code String} |
| */ |
| public String(String original) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new {@code String} so that it represents the sequence of |
| * characters currently contained in the character array argument. The |
| * contents of the character array are copied; subsequent modification of |
| * the character array does not affect the newly created string. |
| * |
| * @param value |
| * The initial value of the string |
| */ |
| public String(char value[]) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new {@code String} that contains characters from a subarray |
| * of the character array argument. The {@code offset} argument is the |
| * index of the first character of the subarray and the {@code count} |
| * argument specifies the length of the subarray. The contents of the |
| * subarray are copied; subsequent modification of the character array does |
| * not affect the newly created string. |
| * |
| * @param value |
| * Array that is the source of characters |
| * |
| * @param offset |
| * The initial offset |
| * |
| * @param count |
| * The length |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} and {@code count} arguments index |
| * characters outside the bounds of the {@code value} array |
| */ |
| public String(char value[], int offset, int count) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new {@code String} that contains characters from a subarray |
| * of the <a href="Character.html#unicode">Unicode code point</a> array |
| * argument. The {@code offset} argument is the index of the first code |
| * point of the subarray and the {@code count} argument specifies the |
| * length of the subarray. The contents of the subarray are converted to |
| * {@code char}s; subsequent modification of the {@code int} array does not |
| * affect the newly created string. |
| * |
| * @param codePoints |
| * Array that is the source of Unicode code points |
| * |
| * @param offset |
| * The initial offset |
| * |
| * @param count |
| * The length |
| * |
| * @throws IllegalArgumentException |
| * If any invalid Unicode code point is found in {@code |
| * codePoints} |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} and {@code count} arguments index |
| * characters outside the bounds of the {@code codePoints} array |
| * |
| * @since 1.5 |
| */ |
| public String(int[] codePoints, int offset, int count) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new {@code String} constructed from a subarray of an array |
| * of 8-bit integer values. |
| * |
| * <p> The {@code offset} argument is the index of the first byte of the |
| * subarray, and the {@code count} argument specifies the length of the |
| * subarray. |
| * |
| * <p> Each {@code byte} in the subarray is converted to a {@code char} as |
| * specified in the method above. |
| * |
| * @deprecated This method does not properly convert bytes into characters. |
| * As of JDK 1.1, the preferred way to do this is via the |
| * {@code String} constructors that take a {@link |
| * java.nio.charset.Charset}, charset name, or that use the platform's |
| * default charset. |
| * |
| * @param ascii |
| * The bytes to be converted to characters |
| * |
| * @param hibyte |
| * The top 8 bits of each 16-bit Unicode code unit |
| * |
| * @param offset |
| * The initial offset |
| * @param count |
| * The length |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} or {@code count} argument is invalid |
| * |
| * @see #String(byte[], int) |
| * @see #String(byte[], int, int, java.lang.String) |
| * @see #String(byte[], int, int, java.nio.charset.Charset) |
| * @see #String(byte[], int, int) |
| * @see #String(byte[], java.lang.String) |
| * @see #String(byte[], java.nio.charset.Charset) |
| * @see #String(byte[]) |
| */ |
| @Deprecated |
| public String(byte ascii[], int hibyte, int offset, int count) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new {@code String} containing characters constructed from |
| * an array of 8-bit integer values. Each character <i>c</i>in the |
| * resulting string is constructed from the corresponding component |
| * <i>b</i> in the byte array such that: |
| * |
| * <blockquote><pre> |
| * <b><i>c</i></b> == (char)(((hibyte & 0xff) << 8) |
| * | (<b><i>b</i></b> & 0xff)) |
| * </pre></blockquote> |
| * |
| * @deprecated This method does not properly convert bytes into |
| * characters. As of JDK 1.1, the preferred way to do this is via the |
| * {@code String} constructors that take a {@link |
| * java.nio.charset.Charset}, charset name, or that use the platform's |
| * default charset. |
| * |
| * @param ascii |
| * The bytes to be converted to characters |
| * |
| * @param hibyte |
| * The top 8 bits of each 16-bit Unicode code unit |
| * |
| * @see #String(byte[], int, int, java.lang.String) |
| * @see #String(byte[], int, int, java.nio.charset.Charset) |
| * @see #String(byte[], int, int) |
| * @see #String(byte[], java.lang.String) |
| * @see #String(byte[], java.nio.charset.Charset) |
| * @see #String(byte[]) |
| */ |
| @Deprecated |
| public String(byte ascii[], int hibyte) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified subarray of |
| * bytes using the specified charset. The length of the new {@code String} |
| * is a function of the charset, and hence may not be equal to the length |
| * of the subarray. |
| * |
| * <p> The behavior of this constructor when the given bytes are not valid |
| * in the given charset is unspecified. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @param offset |
| * The index of the first byte to decode |
| * |
| * @param length |
| * The number of bytes to decode |
| |
| * @param charsetName |
| * The name of a supported {@linkplain java.nio.charset.Charset |
| * charset} |
| * |
| * @throws UnsupportedEncodingException |
| * If the named charset is not supported |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} and {@code length} arguments index |
| * characters outside the bounds of the {@code bytes} array |
| * |
| * @since JDK1.1 |
| */ |
| public String(byte bytes[], int offset, int length, String charsetName) |
| throws UnsupportedEncodingException { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified subarray of |
| * bytes using the specified {@linkplain java.nio.charset.Charset charset}. |
| * The length of the new {@code String} is a function of the charset, and |
| * hence may not be equal to the length of the subarray. |
| * |
| * <p> This method always replaces malformed-input and unmappable-character |
| * sequences with this charset's default replacement string. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @param offset |
| * The index of the first byte to decode |
| * |
| * @param length |
| * The number of bytes to decode |
| * |
| * @param charset |
| * The {@linkplain java.nio.charset.Charset charset} to be used to |
| * decode the {@code bytes} |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} and {@code length} arguments index |
| * characters outside the bounds of the {@code bytes} array |
| * |
| * @since 1.6 |
| */ |
| public String(byte bytes[], int offset, int length, Charset charset) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified array of bytes |
| * using the specified {@linkplain java.nio.charset.Charset charset}. The |
| * length of the new {@code String} is a function of the charset, and hence |
| * may not be equal to the length of the byte array. |
| * |
| * <p> The behavior of this constructor when the given bytes are not valid |
| * in the given charset is unspecified. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @param charsetName |
| * The name of a supported {@linkplain java.nio.charset.Charset |
| * charset} |
| * |
| * @throws UnsupportedEncodingException |
| * If the named charset is not supported |
| * |
| * @since JDK1.1 |
| */ |
| public String(byte bytes[], String charsetName) |
| throws UnsupportedEncodingException { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified array of |
| * bytes using the specified {@linkplain java.nio.charset.Charset charset}. |
| * The length of the new {@code String} is a function of the charset, and |
| * hence may not be equal to the length of the byte array. |
| * |
| * <p> This method always replaces malformed-input and unmappable-character |
| * sequences with this charset's default replacement string. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @param charset |
| * The {@linkplain java.nio.charset.Charset charset} to be used to |
| * decode the {@code bytes} |
| * |
| * @since 1.6 |
| */ |
| public String(byte bytes[], Charset charset) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified subarray of |
| * bytes using the platform's default charset. The length of the new |
| * {@code String} is a function of the charset, and hence may not be equal |
| * to the length of the subarray. |
| * |
| * <p> The behavior of this constructor when the given bytes are not valid |
| * in the default charset is unspecified. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @param offset |
| * The index of the first byte to decode |
| * |
| * @param length |
| * The number of bytes to decode |
| * |
| * @throws IndexOutOfBoundsException |
| * If the {@code offset} and the {@code length} arguments index |
| * characters outside the bounds of the {@code bytes} array |
| * |
| * @since JDK1.1 |
| */ |
| public String(byte bytes[], int offset, int length) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Constructs a new {@code String} by decoding the specified array of bytes |
| * using the platform's default charset. The length of the new {@code |
| * String} is a function of the charset, and hence may not be equal to the |
| * length of the byte array. |
| * |
| * <p> The behavior of this constructor when the given bytes are not valid |
| * in the default charset is unspecified. The {@link |
| * java.nio.charset.CharsetDecoder} class should be used when more control |
| * over the decoding process is required. |
| * |
| * @param bytes |
| * The bytes to be decoded into characters |
| * |
| * @since JDK1.1 |
| */ |
| public String(byte bytes[]) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new string that contains the sequence of characters |
| * currently contained in the string buffer argument. The contents of the |
| * string buffer are copied; subsequent modification of the string buffer |
| * does not affect the newly created string. |
| * |
| * @param buffer |
| * A {@code StringBuffer} |
| */ |
| public String(StringBuffer buffer) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Allocates a new string that contains the sequence of characters |
| * currently contained in the string builder argument. The contents of the |
| * string builder are copied; subsequent modification of the string builder |
| * does not affect the newly created string. |
| * |
| * <p> This constructor is provided to ease migration to {@code |
| * StringBuilder}. Obtaining a string from a string builder via the {@code |
| * toString} method is likely to run faster and is generally preferred. |
| * |
| * @param builder |
| * A {@code StringBuilder} |
| * |
| * @since 1.5 |
| */ |
| public String(StringBuilder builder) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| |
| /** |
| * Package private constructor |
| * |
| * @deprecated Use {@link #String(char[],int,int)} instead. |
| */ |
| @Deprecated |
| String(int offset, int count, char[] value) { |
| throw new UnsupportedOperationException("Use StringFactory instead."); |
| } |
| |
| /** |
| * Returns the length of this string. |
| * The length is equal to the number of <a href="Character.html#unicode">Unicode |
| * code units</a> in the string. |
| * |
| * @return the length of the sequence of characters represented by this |
| * object. |
| */ |
| public int length() { |
| return count; |
| } |
| |
| /** |
| * Returns {@code true} if, and only if, {@link #length()} is {@code 0}. |
| * |
| * @return {@code true} if {@link #length()} is {@code 0}, otherwise |
| * {@code false} |
| * |
| * @since 1.6 |
| */ |
| public boolean isEmpty() { |
| return count == 0; |
| } |
| |
| /** |
| * Returns the {@code char} value at the |
| * specified index. An index ranges from {@code 0} to |
| * {@code length() - 1}. The first {@code char} value of the sequence |
| * is at index {@code 0}, the next at index {@code 1}, |
| * and so on, as for array indexing. |
| * |
| * <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 {@code char} value. |
| * @return the {@code char} value at the specified index of this string. |
| * The first {@code char} value is at index {@code 0}. |
| * @exception IndexOutOfBoundsException if the {@code index} |
| * argument is negative or not less than the length of this |
| * string. |
| */ |
| public native char charAt(int index); |
| |
| native void setCharAt(int index, char c); |
| |
| /** |
| * 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 {@code String}, 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} |
| * @exception IndexOutOfBoundsException if the {@code index} |
| * argument is negative or not less than the length of this |
| * string. |
| * @since 1.5 |
| */ |
| public int codePointAt(int index) { |
| if ((index < 0) || (index >= count)) { |
| throw new StringIndexOutOfBoundsException(index); |
| } |
| return Character.codePointAt(this, index); |
| } |
| |
| /** |
| * 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 |
| * CharSequence#length() 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. |
| * @exception IndexOutOfBoundsException if the {@code index} |
| * argument is less than 1 or greater than the length |
| * of this string. |
| * @since 1.5 |
| */ |
| public int codePointBefore(int index) { |
| int i = index - 1; |
| if ((i < 0) || (i >= count)) { |
| throw new StringIndexOutOfBoundsException(index); |
| } |
| return Character.codePointBefore(this, index); |
| } |
| |
| /** |
| * Returns the number of Unicode code points in the specified text |
| * range of this {@code String}. 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 |
| * the text range 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 |
| * @exception IndexOutOfBoundsException if the |
| * {@code beginIndex} is negative, or {@code endIndex} |
| * is larger than the length of this {@code String}, or |
| * {@code beginIndex} is larger than {@code endIndex}. |
| * @since 1.5 |
| */ |
| public int codePointCount(int beginIndex, int endIndex) { |
| if (beginIndex < 0 || endIndex > count || beginIndex > endIndex) { |
| throw new IndexOutOfBoundsException(); |
| } |
| return Character.codePointCount(this, beginIndex, endIndex); |
| } |
| |
| /** |
| * Returns the index within this {@code String} 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 {@code String} |
| * @exception IndexOutOfBoundsException if {@code index} |
| * is negative or larger then the length of this |
| * {@code String}, or if {@code codePointOffset} is positive |
| * and the substring starting with {@code index} has fewer |
| * than {@code codePointOffset} code points, |
| * or if {@code codePointOffset} is negative and the substring |
| * before {@code index} has fewer than the absolute value |
| * of {@code codePointOffset} code points. |
| * @since 1.5 |
| */ |
| public int offsetByCodePoints(int index, int codePointOffset) { |
| if (index < 0 || index > count) { |
| throw new IndexOutOfBoundsException(); |
| } |
| return Character.offsetByCodePoints(this, index, codePointOffset); |
| } |
| |
| /** |
| * Copy characters from this string into dst starting at dstBegin. |
| * This method doesn't perform any range checking. |
| */ |
| void getChars(char dst[], int dstBegin) { |
| getCharsNoCheck(0, count, dst, dstBegin); |
| } |
| |
| /** |
| * Copies characters from this string into the destination character |
| * array. |
| * <p> |
| * The first character to be copied is at index {@code srcBegin}; |
| * the last character to be copied is at index {@code srcEnd-1} |
| * (thus 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: |
| * <blockquote><pre> |
| * dstBegin + (srcEnd-srcBegin) - 1 |
| * </pre></blockquote> |
| * |
| * @param srcBegin index of the first character in the string |
| * to copy. |
| * @param srcEnd index after the last character in the string |
| * to copy. |
| * @param dst the destination array. |
| * @param dstBegin the start offset in the destination array. |
| * @exception IndexOutOfBoundsException If any of the following |
| * is true: |
| * <ul><li>{@code srcBegin} is negative. |
| * <li>{@code srcBegin} is greater than {@code srcEnd} |
| * <li>{@code srcEnd} is greater than the length of this |
| * string |
| * <li>{@code dstBegin} is negative |
| * <li>{@code dstBegin+(srcEnd-srcBegin)} is larger than |
| * {@code dst.length}</ul> |
| */ |
| public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) { |
| if (dst == null) { |
| throw new NullPointerException("dst == null"); |
| } |
| |
| if (srcBegin < 0) { |
| throw new StringIndexOutOfBoundsException(this, srcBegin); |
| } |
| if (srcEnd > count) { |
| throw new StringIndexOutOfBoundsException(this, srcEnd); |
| } |
| |
| int n = srcEnd - srcBegin; |
| if (srcEnd < srcBegin) { |
| throw new StringIndexOutOfBoundsException(this, srcBegin, n); |
| } |
| |
| if (dstBegin < 0) { |
| throw new ArrayIndexOutOfBoundsException("dstBegin < 0. dstBegin=" + dstBegin); |
| } |
| // dstBegin can be equal to dst.length, but only in the case where zero chars are to be |
| // copied. |
| if (dstBegin > dst.length) { |
| throw new ArrayIndexOutOfBoundsException( |
| "dstBegin > dst.length. dstBegin=" + dstBegin + ", dst.length=" + dst.length); |
| } |
| if (n > dst.length - dstBegin) { |
| throw new ArrayIndexOutOfBoundsException( |
| "n > dst.length - dstBegin. n=" + n + ", dst.length=" + dst.length |
| + "dstBegin=" + dstBegin); |
| } |
| |
| getCharsNoCheck(srcBegin, srcEnd, dst, dstBegin); |
| } |
| |
| /** |
| * getChars without bounds checks, for use by other classes |
| * within the java.lang package only. The caller is responsible for |
| * ensuring that start >= 0 && start <= end && end <= count. |
| */ |
| native void getCharsNoCheck(int start, int end, char[] buffer, int index); |
| |
| |
| /** |
| * Copies characters from this string into the destination byte array. Each |
| * byte receives the 8 low-order bits of the corresponding character. The |
| * eight high-order bits of each character are not copied and do not |
| * participate in the transfer in any way. |
| * |
| * <p> 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, converted to bytes, are copied into the subarray of {@code |
| * dst} starting at index {@code dstBegin} and ending at index: |
| * |
| * <blockquote><pre> |
| * dstBegin + (srcEnd-srcBegin) - 1 |
| * </pre></blockquote> |
| * |
| * @deprecated This method does not properly convert characters into |
| * bytes. As of JDK 1.1, the preferred way to do this is via the |
| * {@link #getBytes()} method, which uses the platform's default charset. |
| * |
| * @param srcBegin |
| * Index of the first character in the string to copy |
| * |
| * @param srcEnd |
| * Index after the last character in the string to copy |
| * |
| * @param dst |
| * The destination array |
| * |
| * @param dstBegin |
| * The start offset in the destination array |
| * |
| * @throws IndexOutOfBoundsException |
| * If any of the following is true: |
| * <ul> |
| * <li> {@code srcBegin} is negative |
| * <li> {@code srcBegin} is greater than {@code srcEnd} |
| * <li> {@code srcEnd} is greater than the length of this String |
| * <li> {@code dstBegin} is negative |
| * <li> {@code dstBegin+(srcEnd-srcBegin)} is larger than {@code |
| * dst.length} |
| * </ul> |
| */ |
| @Deprecated |
| public void getBytes(int srcBegin, int srcEnd, byte dst[], int dstBegin) { |
| if (srcBegin < 0) { |
| throw new StringIndexOutOfBoundsException(this, srcBegin); |
| } |
| if (srcEnd > count) { |
| throw new StringIndexOutOfBoundsException(this, srcEnd); |
| } |
| if (srcBegin > srcEnd) { |
| throw new StringIndexOutOfBoundsException(this, (srcEnd - srcBegin)); |
| } |
| |
| int j = dstBegin; |
| int n = srcEnd; |
| int i = srcBegin; |
| |
| while (i < n) { |
| dst[j++] = (byte)charAt(i++); |
| } |
| } |
| |
| /** |
| * Encodes this {@code String} into a sequence of bytes using the named |
| * charset, storing the result into a new byte array. |
| * |
| * <p> The behavior of this method when this string cannot be encoded in |
| * the given charset is unspecified. The {@link |
| * java.nio.charset.CharsetEncoder} class should be used when more control |
| * over the encoding process is required. |
| * |
| * @param charsetName |
| * The name of a supported {@linkplain java.nio.charset.Charset |
| * charset} |
| * |
| * @return The resultant byte array |
| * |
| * @throws UnsupportedEncodingException |
| * If the named charset is not supported |
| * |
| * @since JDK1.1 |
| */ |
| public byte[] getBytes(String charsetName) |
| throws UnsupportedEncodingException { |
| if (charsetName == null) throw new NullPointerException(); |
| return getBytes(Charset.forNameUEE(charsetName)); |
| } |
| |
| /** |
| * Encodes this {@code String} into a sequence of bytes using the given |
| * {@linkplain java.nio.charset.Charset charset}, storing the result into a |
| * new byte array. |
| * |
| * <p> This method always replaces malformed-input and unmappable-character |
| * sequences with this charset's default replacement byte array. The |
| * {@link java.nio.charset.CharsetEncoder} class should be used when more |
| * control over the encoding process is required. |
| * |
| * @param charset |
| * The {@linkplain java.nio.charset.Charset} to be used to encode |
| * the {@code String} |
| * |
| * @return The resultant byte array |
| * |
| * @since 1.6 |
| */ |
| public byte[] getBytes(Charset charset) { |
| if (charset == null) { |
| throw new NullPointerException("charset == null"); |
| } |
| |
| final String name = charset.name(); |
| if ("UTF-8".equals(name)) { |
| return CharsetUtils.toUtf8Bytes(this, 0, count); |
| } else if ("ISO-8859-1".equals(name)) { |
| return CharsetUtils.toIsoLatin1Bytes(this, 0, count); |
| } else if ("US-ASCII".equals(name)) { |
| return CharsetUtils.toAsciiBytes(this, 0, count); |
| } else if ("UTF-16BE".equals(name)) { |
| return CharsetUtils.toBigEndianUtf16Bytes(this, 0, count); |
| } |
| |
| return StringCoding.encode(charset, this); |
| } |
| |
| /** |
| * Encodes this {@code String} into a sequence of bytes using the |
| * platform's default charset, storing the result into a new byte array. |
| * |
| * <p> The behavior of this method when this string cannot be encoded in |
| * the default charset is unspecified. The {@link |
| * java.nio.charset.CharsetEncoder} class should be used when more control |
| * over the encoding process is required. |
| * |
| * @return The resultant byte array |
| * |
| * @since JDK1.1 |
| */ |
| public byte[] getBytes() { |
| return getBytes(Charset.defaultCharset()); |
| } |
| |
| /** |
| * Compares this string to the specified object. The result is {@code |
| * true} if and only if the argument is not {@code null} and is a {@code |
| * String} object that represents the same sequence of characters as this |
| * object. |
| * |
| * @param anObject |
| * The object to compare this {@code String} against |
| * |
| * @return {@code true} if the given object represents a {@code String} |
| * equivalent to this string, {@code false} otherwise |
| * |
| * @see #compareTo(String) |
| * @see #equalsIgnoreCase(String) |
| */ |
| public boolean equals(Object anObject) { |
| if (this == anObject) { |
| return true; |
| } |
| if (anObject instanceof String) { |
| String anotherString = (String) anObject; |
| int n = count; |
| if (n == anotherString.count) { |
| int i = 0; |
| while (n-- != 0) { |
| if (charAt(i) != anotherString.charAt(i)) |
| return false; |
| i++; |
| } |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Compares this string to the specified {@code StringBuffer}. The result |
| * is {@code true} if and only if this {@code String} represents the same |
| * sequence of characters as the specified {@code StringBuffer}. This method |
| * synchronizes on the {@code StringBuffer}. |
| * |
| * @param sb |
| * The {@code StringBuffer} to compare this {@code String} against |
| * |
| * @return {@code true} if this {@code String} represents the same |
| * sequence of characters as the specified {@code StringBuffer}, |
| * {@code false} otherwise |
| * |
| * @since 1.4 |
| */ |
| public boolean contentEquals(StringBuffer sb) { |
| return contentEquals((CharSequence)sb); |
| } |
| |
| private boolean nonSyncContentEquals(AbstractStringBuilder sb) { |
| char v2[] = sb.getValue(); |
| int n = count; |
| if (n != sb.length()) { |
| return false; |
| } |
| for (int i = 0; i < n; i++) { |
| if (charAt(i) != v2[i]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Compares this string to the specified {@code CharSequence}. The |
| * result is {@code true} if and only if this {@code String} represents the |
| * same sequence of char values as the specified sequence. Note that if the |
| * {@code CharSequence} is a {@code StringBuffer} then the method |
| * synchronizes on it. |
| * |
| * @param cs |
| * The sequence to compare this {@code String} against |
| * |
| * @return {@code true} if this {@code String} represents the same |
| * sequence of char values as the specified sequence, {@code |
| * false} otherwise |
| * |
| * @since 1.5 |
| */ |
| public boolean contentEquals(CharSequence cs) { |
| // Argument is a StringBuffer, StringBuilder |
| if (cs instanceof AbstractStringBuilder) { |
| if (cs instanceof StringBuffer) { |
| synchronized(cs) { |
| return nonSyncContentEquals((AbstractStringBuilder)cs); |
| } |
| } else { |
| return nonSyncContentEquals((AbstractStringBuilder)cs); |
| } |
| } |
| // Argument is a String |
| if (cs instanceof String) { |
| return equals(cs); |
| } |
| // Argument is a generic CharSequence |
| int n = count; |
| if (n != cs.length()) { |
| return false; |
| } |
| for (int i = 0; i < n; i++) { |
| if (charAt(i) != cs.charAt(i)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Compares this {@code String} to another {@code String}, ignoring case |
| * considerations. Two strings are considered equal ignoring case if they |
| * are of the same length and corresponding characters in the two strings |
| * are equal ignoring case. |
| * |
| * <p> Two characters {@code c1} and {@code c2} are considered the same |
| * ignoring case if at least one of the following is true: |
| * <ul> |
| * <li> The two characters are the same (as compared by the |
| * {@code ==} operator) |
| * <li> Applying the method {@link |
| * java.lang.Character#toUpperCase(char)} to each character |
| * produces the same result |
| * <li> Applying the method {@link |
| * java.lang.Character#toLowerCase(char)} to each character |
| * produces the same result |
| * </ul> |
| * |
| * @param anotherString |
| * The {@code String} to compare this {@code String} against |
| * |
| * @return {@code true} if the argument is not {@code null} and it |
| * represents an equivalent {@code String} ignoring case; {@code |
| * false} otherwise |
| * |
| * @see #equals(Object) |
| */ |
| public boolean equalsIgnoreCase(String anotherString) { |
| return (this == anotherString) ? true |
| : (anotherString != null) |
| && (anotherString.count == count) |
| && regionMatches(true, 0, anotherString, 0, count); |
| } |
| |
| /** |
| * Compares two strings lexicographically. |
| * The comparison is based on the Unicode value of each character in |
| * the strings. The character sequence represented by this |
| * {@code String} object is compared lexicographically to the |
| * character sequence represented by the argument string. The result is |
| * a negative integer if this {@code String} object |
| * lexicographically precedes the argument string. The result is a |
| * positive integer if this {@code String} object lexicographically |
| * follows the argument string. The result is zero if the strings |
| * are equal; {@code compareTo} returns {@code 0} exactly when |
| * the {@link #equals(Object)} method would return {@code true}. |
| * <p> |
| * This is the definition of lexicographic ordering. If two strings are |
| * different, then either they have different characters at some index |
| * that is a valid index for both strings, or their lengths are different, |
| * or both. If they have different characters at one or more index |
| * positions, let <i>k</i> be the smallest such index; then the string |
| * whose character at position <i>k</i> has the smaller value, as |
| * determined by using the < operator, lexicographically precedes the |
| * other string. In this case, {@code compareTo} returns the |
| * difference of the two character values at position {@code k} in |
| * the two string -- that is, the value: |
| * <blockquote><pre> |
| * this.charAt(k)-anotherString.charAt(k) |
| * </pre></blockquote> |
| * If there is no index position at which they differ, then the shorter |
| * string lexicographically precedes the longer string. In this case, |
| * {@code compareTo} returns the difference of the lengths of the |
| * strings -- that is, the value: |
| * <blockquote><pre> |
| * this.length()-anotherString.length() |
| * </pre></blockquote> |
| * |
| * @param anotherString the {@code String} to be compared. |
| * @return the value {@code 0} if the argument string is equal to |
| * this string; a value less than {@code 0} if this string |
| * is lexicographically less than the string argument; and a |
| * value greater than {@code 0} if this string is |
| * lexicographically greater than the string argument. |
| */ |
| public native int compareTo(String anotherString); |
| |
| /** |
| * A Comparator that orders {@code String} objects as by |
| * {@code compareToIgnoreCase}. This comparator is serializable. |
| * <p> |
| * Note that this Comparator does <em>not</em> take locale into account, |
| * and will result in an unsatisfactory ordering for certain locales. |
| * The java.text package provides <em>Collators</em> to allow |
| * locale-sensitive ordering. |
| * |
| * @see java.text.Collator#compare(String, String) |
| * @since 1.2 |
| */ |
| public static final Comparator<String> CASE_INSENSITIVE_ORDER |
| = new CaseInsensitiveComparator(); |
| private static class CaseInsensitiveComparator |
| implements Comparator<String>, java.io.Serializable { |
| // use serialVersionUID from JDK 1.2.2 for interoperability |
| private static final long serialVersionUID = 8575799808933029326L; |
| |
| public int compare(String s1, String s2) { |
| int n1 = s1.length(); |
| int n2 = s2.length(); |
| int min = Math.min(n1, n2); |
| for (int i = 0; i < min; i++) { |
| char c1 = s1.charAt(i); |
| char c2 = s2.charAt(i); |
| if (c1 != c2) { |
| c1 = Character.toUpperCase(c1); |
| c2 = Character.toUpperCase(c2); |
| if (c1 != c2) { |
| c1 = Character.toLowerCase(c1); |
| c2 = Character.toLowerCase(c2); |
| if (c1 != c2) { |
| // No overflow because of numeric promotion |
| return c1 - c2; |
| } |
| } |
| } |
| } |
| return n1 - n2; |
| } |
| |
| /** Replaces the de-serialized object. */ |
| private Object readResolve() { return CASE_INSENSITIVE_ORDER; } |
| } |
| |
| /** |
| * Compares two strings lexicographically, ignoring case |
| * differences. This method returns an integer whose sign is that of |
| * calling {@code compareTo} with normalized versions of the strings |
| * where case differences have been eliminated by calling |
| * {@code Character.toLowerCase(Character.toUpperCase(character))} on |
| * each character. |
| * <p> |
| * Note that this method does <em>not</em> take locale into account, |
| * and will result in an unsatisfactory ordering for certain locales. |
| * The java.text package provides <em>collators</em> to allow |
| * locale-sensitive ordering. |
| * |
| * @param str the {@code String} to be compared. |
| * @return a negative integer, zero, or a positive integer as the |
| * specified String is greater than, equal to, or less |
| * than this String, ignoring case considerations. |
| * @see java.text.Collator#compare(String, String) |
| * @since 1.2 |
| */ |
| public int compareToIgnoreCase(String str) { |
| return CASE_INSENSITIVE_ORDER.compare(this, str); |
| } |
| |
| /** |
| * Tests if two string regions are equal. |
| * <p> |
| * A substring of this {@code String} object is compared to a substring |
| * of the argument other. The result is true if these substrings |
| * represent identical character sequences. The substring of this |
| * {@code String} object to be compared begins at index {@code toffset} |
| * and has length {@code len}. The substring of other to be compared |
| * begins at index {@code ooffset} and has length {@code len}. The |
| * result is {@code false} if and only if at least one of the following |
| * is true: |
| * <ul><li>{@code toffset} is negative. |
| * <li>{@code ooffset} is negative. |
| * <li>{@code toffset+len} is greater than the length of this |
| * {@code String} object. |
| * <li>{@code ooffset+len} is greater than the length of the other |
| * argument. |
| * <li>There is some nonnegative integer <i>k</i> less than {@code len} |
| * such that: |
| * {@code this.charAt(toffset + }<i>k</i>{@code ) != other.charAt(ooffset + } |
| * <i>k</i>{@code )} |
| * </ul> |
| * |
| * @param toffset the starting offset of the subregion in this string. |
| * @param other the string argument. |
| * @param ooffset the starting offset of the subregion in the string |
| * argument. |
| * @param len the number of characters to compare. |
| * @return {@code true} if the specified subregion of this string |
| * exactly matches the specified subregion of the string argument; |
| * {@code false} otherwise. |
| */ |
| public boolean regionMatches(int toffset, String other, int ooffset, |
| int len) { |
| int to = toffset; |
| int po = ooffset; |
| // Note: toffset, ooffset, or len might be near -1>>>1. |
| if ((ooffset < 0) || (toffset < 0) |
| || (toffset > (long)count - len) |
| || (ooffset > (long)other.count - len)) { |
| return false; |
| } |
| while (len-- > 0) { |
| if (charAt(to++) != other.charAt(po++)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Tests if two string regions are equal. |
| * <p> |
| * A substring of this {@code String} object is compared to a substring |
| * of the argument {@code other}. The result is {@code true} if these |
| * substrings represent character sequences that are the same, ignoring |
| * case if and only if {@code ignoreCase} is true. The substring of |
| * this {@code String} object to be compared begins at index |
| * {@code toffset} and has length {@code len}. The substring of |
| * {@code other} to be compared begins at index {@code ooffset} and |
| * has length {@code len}. The result is {@code false} if and only if |
| * at least one of the following is true: |
| * <ul><li>{@code toffset} is negative. |
| * <li>{@code ooffset} is negative. |
| * <li>{@code toffset+len} is greater than the length of this |
| * {@code String} object. |
| * <li>{@code ooffset+len} is greater than the length of the other |
| * argument. |
| * <li>{@code ignoreCase} is {@code false} and there is some nonnegative |
| * integer <i>k</i> less than {@code len} such that: |
| * <blockquote><pre> |
| * this.charAt(toffset+k) != other.charAt(ooffset+k) |
| * </pre></blockquote> |
| * <li>{@code ignoreCase} is {@code true} and there is some nonnegative |
| * integer <i>k</i> less than {@code len} such that: |
| * <blockquote><pre> |
| * Character.toLowerCase(this.charAt(toffset+k)) != |
| Character.toLowerCase(other.charAt(ooffset+k)) |
| * </pre></blockquote> |
| * and: |
| * <blockquote><pre> |
| * Character.toUpperCase(this.charAt(toffset+k)) != |
| * Character.toUpperCase(other.charAt(ooffset+k)) |
| * </pre></blockquote> |
| * </ul> |
| * |
| * @param ignoreCase if {@code true}, ignore case when comparing |
| * characters. |
| * @param toffset the starting offset of the subregion in this |
| * string. |
| * @param other the string argument. |
| * @param ooffset the starting offset of the subregion in the string |
| * argument. |
| * @param len the number of characters to compare. |
| * @return {@code true} if the specified subregion of this string |
| * matches the specified subregion of the string argument; |
| * {@code false} otherwise. Whether the matching is exact |
| * or case insensitive depends on the {@code ignoreCase} |
| * argument. |
| */ |
| public boolean regionMatches(boolean ignoreCase, int toffset, |
| String other, int ooffset, int len) { |
| int to = toffset; |
| int po = ooffset; |
| // Note: toffset, ooffset, or len might be near -1>>>1. |
| if ((ooffset < 0) || (toffset < 0) |
| || (toffset > (long)count - len) |
| || (ooffset > (long)other.count - len)) { |
| return false; |
| } |
| while (len-- > 0) { |
| char c1 = charAt(to++); |
| char c2 = other.charAt(po++); |
| if (c1 == c2) { |
| continue; |
| } |
| if (ignoreCase) { |
| // If characters don't match but case may be ignored, |
| // try converting both characters to uppercase. |
| // If the results match, then the comparison scan should |
| // continue. |
| char u1 = Character.toUpperCase(c1); |
| char u2 = Character.toUpperCase(c2); |
| if (u1 == u2) { |
| continue; |
| } |
| // Unfortunately, conversion to uppercase does not work properly |
| // for the Georgian alphabet, which has strange rules about case |
| // conversion. So we need to make one last check before |
| // exiting. |
| if (Character.toLowerCase(u1) == Character.toLowerCase(u2)) { |
| continue; |
| } |
| } |
| return false; |
| } |
| return true; |
| } |
| |
| /** |
| * Tests if the substring of this string beginning at the |
| * specified index starts with the specified prefix. |
| * |
| * @param prefix the prefix. |
| * @param toffset where to begin looking in this string. |
| * @return {@code true} if the character sequence represented by the |
| * argument is a prefix of the substring of this object starting |
| * at index {@code toffset}; {@code false} otherwise. |
| * The result is {@code false} if {@code toffset} is |
| * negative or greater than the length of this |
| * {@code String} object; otherwise the result is the same |
| * as the result of the expression |
| * <pre> |
| * this.substring(toffset).startsWith(prefix) |
| * </pre> |
| */ |
| public boolean startsWith(String prefix, int toffset) { |
| int to = toffset; |
| int po = 0; |
| int pc = prefix.count; |
| // Note: toffset might be near -1>>>1. |
| if ((toffset < 0) || (toffset > count - pc)) { |
| return false; |
| } |
| while (--pc >= 0) { |
| if (charAt(to++) != prefix.charAt(po++)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Tests if this string starts with the specified prefix. |
| * |
| * @param prefix the prefix. |
| * @return {@code true} if the character sequence represented by the |
| * argument is a prefix of the character sequence represented by |
| * this string; {@code false} otherwise. |
| * Note also that {@code true} will be returned if the |
| * argument is an empty string or is equal to this |
| * {@code String} object as determined by the |
| * {@link #equals(Object)} method. |
| * @since 1. 0 |
| */ |
| public boolean startsWith(String prefix) { |
| return startsWith(prefix, 0); |
| } |
| |
| /** |
| * Tests if this string ends with the specified suffix. |
| * |
| * @param suffix the suffix. |
| * @return {@code true} if the character sequence represented by the |
| * argument is a suffix of the character sequence represented by |
| * this object; {@code false} otherwise. Note that the |
| * result will be {@code true} if the argument is the |
| * empty string or is equal to this {@code String} object |
| * as determined by the {@link #equals(Object)} method. |
| */ |
| public boolean endsWith(String suffix) { |
| return startsWith(suffix, count - suffix.count); |
| } |
| |
| /** |
| * Returns a hash code for this string. The hash code for a |
| * {@code String} object is computed as |
| * <blockquote><pre> |
| * s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1] |
| * </pre></blockquote> |
| * using {@code int} arithmetic, where {@code s[i]} is the |
| * <i>i</i>th character of the string, {@code n} is the length of |
| * the string, and {@code ^} indicates exponentiation. |
| * (The hash value of the empty string is zero.) |
| * |
| * @return a hash code value for this object. |
| */ |
| public int hashCode() { |
| int h = hash; |
| if (h == 0 && count > 0) { |
| for (int i = 0; i < count; i++) { |
| h = 31 * h + charAt(i); |
| } |
| hash = h; |
| } |
| return h; |
| } |
| |
| /** |
| * Returns the index within this string of the first occurrence of |
| * the specified character. If a character with value |
| * {@code ch} occurs in the character sequence represented by |
| * this {@code String} object, then the index (in Unicode |
| * code units) of the first such occurrence is returned. For |
| * values of {@code ch} in the range from 0 to 0xFFFF |
| * (inclusive), this is the smallest value <i>k</i> such that: |
| * <blockquote><pre> |
| * this.charAt(<i>k</i>) == ch |
| * </pre></blockquote> |
| * is true. For other values of {@code ch}, it is the |
| * smallest value <i>k</i> such that: |
| * <blockquote><pre> |
| * this.codePointAt(<i>k</i>) == ch |
| * </pre></blockquote> |
| * is true. In either case, if no such character occurs in this |
| * string, then {@code -1} is returned. |
| * |
| * @param ch a character (Unicode code point). |
| * @return the index of the first occurrence of the character in the |
| * character sequence represented by this object, or |
| * {@code -1} if the character does not occur. |
| */ |
| public int indexOf(int ch) { |
| return indexOf(ch, 0); |
| } |
| |
| /** |
| * Returns the index within this string of the first occurrence of the |
| * specified character, starting the search at the specified index. |
| * <p> |
| * If a character with value {@code ch} occurs in the |
| * character sequence represented by this {@code String} |
| * object at an index no smaller than {@code fromIndex}, then |
| * the index of the first such occurrence is returned. For values |
| * of {@code ch} in the range from 0 to 0xFFFF (inclusive), |
| * this is the smallest value <i>k</i> such that: |
| * <blockquote><pre> |
| * (this.charAt(<i>k</i>) == ch) {@code &&} (<i>k</i> >= fromIndex) |
| * </pre></blockquote> |
| * is true. For other values of {@code ch}, it is the |
| * smallest value <i>k</i> such that: |
| * <blockquote><pre> |
| * (this.codePointAt(<i>k</i>) == ch) {@code &&} (<i>k</i> >= fromIndex) |
| * </pre></blockquote> |
| * is true. In either case, if no such character occurs in this |
| * string at or after position {@code fromIndex}, then |
| * {@code -1} is returned. |
| * |
| * <p> |
| * There is no restriction on the value of {@code fromIndex}. If it |
| * is negative, it has the same effect as if it were zero: this entire |
| * string may be searched. If it is greater than the length of this |
| * string, it has the same effect as if it were equal to the length of |
| * this string: {@code -1} is returned. |
| * |
| * <p>All indices are specified in {@code char} values |
| * (Unicode code units). |
| * |
| * @param ch a character (Unicode code point). |
| * @param fromIndex the index to start the search from. |
| * @return the index of the first occurrence of the character in the |
| * character sequence represented by this object that is greater |
| * than or equal to {@code fromIndex}, or {@code -1} |
| * if the character does not occur. |
| */ |
| public int indexOf(int ch, int fromIndex) { |
| final int max = count; |
| if (fromIndex < 0) { |
| fromIndex = 0; |
| } else if (fromIndex >= max) { |
| // Note: fromIndex might be near -1>>>1. |
| return -1; |
| } |
| |
| if (ch < Character.MIN_SUPPLEMENTARY_CODE_POINT) { |
| // handle most cases here (ch is a BMP code point or a |
| // negative value (invalid code point)) |
| for (int i = fromIndex; i < max; i++) { |
| if (charAt(i) == ch) { |
| return i; |
| } |
| } |
| return -1; |
| } else { |
| return indexOfSupplementary(ch, fromIndex); |
| } |
| } |
| |
| private native int fastIndexOf(int c, int start); |
| |
| /** |
| * Handles (rare) calls of indexOf with a supplementary character. |
| */ |
| private int indexOfSupplementary(int ch, int fromIndex) { |
| if (Character.isValidCodePoint(ch)) { |
| final char hi = Character.highSurrogate(ch); |
| final char lo = Character.lowSurrogate(ch); |
| final int max = count - 1; |
| for (int i = fromIndex; i < max; i++) { |
| if (charAt(i) == hi && charAt(i + 1) == lo) { |
| return i; |
| } |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Returns the index within this string of the last occurrence of |
| * the specified character. For values of {@code ch} in the |
| * range from 0 to 0xFFFF (inclusive), the index (in Unicode code |
| * units) returned is the largest value <i>k</i> such that: |
| * <blockquote><pre> |
| * this.charAt(<i>k</i>) == ch |
| * </pre></blockquote> |
| * is true. For other values of {@code ch}, it is the |
| * largest value <i>k</i> such that: |
| * <blockquote><pre> |
| * this.codePointAt(<i>k</i>) == ch |
| * </pre></blockquote> |
| * is true. In either case, if no such character occurs in this |
| * string, then {@code -1} is returned. The |
| * {@code String} is searched backwards starting at the last |
| * character. |
| * |
| * @param ch a character (Unicode code point). |
| * @return the index of the last occurrence of the character in the |
| * character sequence represented by this object, or |
| * {@code -1} if the character does not occur. |
| */ |
| public int lastIndexOf(int ch) { |
| return lastIndexOf(ch, count - 1); |
| } |
| |
| /** |
| * Returns the index within this string of the last occurrence of |
| * the specified character, searching backward starting at the |
| * specified index. For values of {@code ch} in the range |
| * from 0 to 0xFFFF (inclusive), the index returned is the largest |
| * value <i>k</i> such that: |
| * <blockquote><pre> |
| * (this.charAt(<i>k</i>) == ch) {@code &&} (<i>k</i> <= fromIndex) |
| * </pre></blockquote> |
| * is true. For other values of {@code ch}, it is the |
| * largest value <i>k</i> such that: |
| * <blockquote><pre> |
| * (this.codePointAt(<i>k</i>) == ch) {@code &&} (<i>k</i> <= fromIndex) |
| * </pre></blockquote> |
| * is true. In either case, if no such character occurs in this |
| * string at or before position {@code fromIndex}, then |
| * {@code -1} is returned. |
| * |
| * <p>All indices are specified in {@code char} values |
| * (Unicode code units). |
| * |
| * @param ch a character (Unicode code point). |
| * @param fromIndex the index to start the search from. There is no |
| * restriction on the value of {@code fromIndex}. If it is |
| * greater than or equal to the length of this string, it has |
| * the same effect as if it were equal to one less than the |
| * length of this string: this entire string may be searched. |
| * If it is negative, it has the same effect as if it were -1: |
| * -1 is returned. |
| * @return the index of the last occurrence of the character in the |
| * character sequence represented by this object that is less |
| * than or equal to {@code fromIndex}, or {@code -1} |
| * if the character does not occur before that point. |
| */ |
| public int lastIndexOf(int ch, int fromIndex) { |
| if (ch < Character.MIN_SUPPLEMENTARY_CODE_POINT) { |
| // handle most cases here (ch is a BMP code point or a |
| // negative value (invalid code point)) |
| int i = Math.min(fromIndex, count - 1); |
| for (; i >= 0; i--) { |
| if (charAt(i) == ch) { |
| return i; |
| } |
| } |
| return -1; |
| } else { |
| return lastIndexOfSupplementary(ch, fromIndex); |
| } |
| } |
| |
| /** |
| * Handles (rare) calls of lastIndexOf with a supplementary character. |
| */ |
| private int lastIndexOfSupplementary(int ch, int fromIndex) { |
| if (Character.isValidCodePoint(ch)) { |
| char hi = Character.highSurrogate(ch); |
| char lo = Character.lowSurrogate(ch); |
| int i = Math.min(fromIndex, count - 2); |
| for (; i >= 0; i--) { |
| if (charAt(i) == hi && charAt(i + 1) == lo) { |
| return i; |
| } |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Returns the index within this string of the first occurrence of the |
| * specified substring. |
| * |
| * <p>The returned index is the smallest value <i>k</i> for which: |
| * <blockquote><pre> |
| * this.startsWith(str, <i>k</i>) |
| * </pre></blockquote> |
| * If no such value of <i>k</i> exists, then {@code -1} is returned. |
| * |
| * @param str the substring to search for. |
| * @return the index of the first occurrence of the specified substring, |
| * or {@code -1} if there is no such occurrence. |
| */ |
| public int indexOf(String str) { |
| return indexOf(str, 0); |
| } |
| |
| /** |
| * Returns the index within this string of the first occurrence of the |
| * specified substring, starting at the specified index. |
| * |
| * <p>The returned index is the smallest value <i>k</i> for which: |
| * <blockquote><pre> |
| * <i>k</i> >= fromIndex {@code &&} this.startsWith(str, <i>k</i>) |
| * </pre></blockquote> |
| * If no such value of <i>k</i> exists, then {@code -1} is returned. |
| * |
| * @param str the substring to search for. |
| * @param fromIndex the index from which to start the search. |
| * @return the index of the first occurrence of the specified substring, |
| * starting at the specified index, |
| * or {@code -1} if there is no such occurrence. |
| */ |
| public int indexOf(String str, int fromIndex) { |
| return indexOf(this, str, fromIndex); |
| } |
| |
| /** |
| * Code shared by String and AbstractStringBuilder to do searches. The |
| * source is the character array being searched, and the target |
| * is the string being searched for. |
| * |
| * @param source the characters being searched. |
| * @param target the characters being searched for. |
| * @param fromIndex the index to begin searching from. |
| */ |
| static int indexOf(String source, |
| String target, |
| int fromIndex) { |
| if (fromIndex >= source.count) { |
| return (target.count == 0 ? source.count : -1); |
| } |
| if (fromIndex < 0) { |
| fromIndex = 0; |
| } |
| if (target.count == 0) { |
| return fromIndex; |
| } |
| |
| char first = target.charAt(0); |
| int max = (source.count - target.count); |
| |
| for (int i = fromIndex; i <= max; i++) { |
| /* Look for first character. */ |
| if (source.charAt(i)!= first) { |
| while (++i <= max && source.charAt(i) != first); |
| } |
| |
| /* Found first character, now look at the rest of v2 */ |
| if (i <= max) { |
| int j = i + 1; |
| int end = j + target.count - 1; |
| for (int k = 1; j < end && source.charAt(j) |
| == target.charAt(k); j++, k++); |
| |
| if (j == end) { |
| /* Found whole string. */ |
| return i; |
| } |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Code shared by String and StringBuffer to do searches. The |
| * source is the character array being searched, and the target |
| * is the string being searched for. |
| * |
| * @param source the characters being searched. |
| * @param sourceOffset offset of the source string. |
| * @param sourceCount count of the source string. |
| * @param target the characters being searched for. |
| * @param targetOffset offset of the target string. |
| * @param targetCount count of the target string. |
| * @param fromIndex the index to begin searching from. |
| */ |
| static int indexOf(char[] source, int sourceOffset, int sourceCount, |
| char[] target, int targetOffset, int targetCount, |
| int fromIndex) { |
| if (fromIndex >= sourceCount) { |
| return (targetCount == 0 ? sourceCount : -1); |
| } |
| if (fromIndex < 0) { |
| fromIndex = 0; |
| } |
| if (targetCount == 0) { |
| return fromIndex; |
| } |
| |
| char first = target[targetOffset]; |
| int max = sourceOffset + (sourceCount - targetCount); |
| |
| for (int i = sourceOffset + fromIndex; i <= max; i++) { |
| /* Look for first character. */ |
| if (source[i] != first) { |
| while (++i <= max && source[i] != first); |
| } |
| |
| /* Found first character, now look at the rest of v2 */ |
| if (i <= max) { |
| int j = i + 1; |
| int end = j + targetCount - 1; |
| for (int k = targetOffset + 1; j < end && source[j] |
| == target[k]; j++, k++); |
| |
| if (j == end) { |
| /* Found whole string. */ |
| return i - sourceOffset; |
| } |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Returns the index within this string of the last occurrence of the |
| * specified substring. The last occurrence of the empty string "" |
| * is considered to occur at the index value {@code this.length()}. |
| * |
| * <p>The returned index is the largest value <i>k</i> for which: |
| * <blockquote><pre> |
| * this.startsWith(str, <i>k</i>) |
| * </pre></blockquote> |
| * If no such value of <i>k</i> exists, then {@code -1} is returned. |
| * |
| * @param str the substring to search for. |
| * @return the index of the last occurrence of the specified substring, |
| * or {@code -1} if there is no such occurrence. |
| */ |
| public int lastIndexOf(String str) { |
| return lastIndexOf(str, count); |
| } |
| |
| /** |
| * Returns the index within this string of the last occurrence of the |
| * specified substring, searching backward starting at the specified index. |
| * |
| * <p>The returned index is the largest value <i>k</i> for which: |
| * <blockquote><pre> |
| * <i>k</i> {@code <=} fromIndex {@code &&} this.startsWith(str, <i>k</i>) |
| * </pre></blockquote> |
| * If no such value of <i>k</i> exists, then {@code -1} is returned. |
| * |
| * @param str the substring to search for. |
| * @param fromIndex the index to start the search from. |
| * @return the index of the last occurrence of the specified substring, |
| * searching backward from the specified index, |
| * or {@code -1} if there is no such occurrence. |
| */ |
| public int lastIndexOf(String str, int fromIndex) { |
| return lastIndexOf(this, str, fromIndex); |
| } |
| |
| /** |
| * Code shared by String and AbstractStringBuilder to do searches. The |
| * source is the character array being searched, and the target |
| * is the string being searched for. |
| * |
| * @param source the characters being searched. |
| * @param target the characters being searched for. |
| * @param fromIndex the index to begin searching from. |
| */ |
| static int lastIndexOf(String source, |
| String target, |
| int fromIndex) { |
| /* |
| * Check arguments; return immediately where possible. For |
| * consistency, don't check for null str. |
| */ |
| int rightIndex = source.count - target.count; |
| if (fromIndex < 0) { |
| return -1; |
| } |
| if (fromIndex > rightIndex) { |
| fromIndex = rightIndex; |
| } |
| /* Empty string always matches. */ |
| if (target.count == 0) { |
| return fromIndex; |
| } |
| |
| int strLastIndex = target.count - 1; |
| char strLastChar = target.charAt(strLastIndex); |
| int min = target.count - 1; |
| int i = min + fromIndex; |
| |
| startSearchForLastChar: |
| while (true) { |
| while (i >= min && source.charAt(i) != strLastChar) { |
| i--; |
| } |
| if (i < min) { |
| return -1; |
| } |
| int j = i - 1; |
| int start = j - (target.count - 1); |
| int k = strLastIndex - 1; |
| |
| while (j > start) { |
| if (source.charAt(j--) != target.charAt(k--)) { |
| i--; |
| continue startSearchForLastChar; |
| } |
| } |
| return start + 1; |
| } |
| } |
| |
| /** |
| * Code shared by String and StringBuffer to do searches. The |
| * source is the character array being searched, and the target |
| * is the string being searched for. |
| * |
| * @param source the characters being searched. |
| * @param sourceOffset offset of the source string. |
| * @param sourceCount count of the source string. |
| * @param target the characters being searched for. |
| * @param targetOffset offset of the target string. |
| * @param targetCount count of the target string. |
| * @param fromIndex the index to begin searching from. |
| */ |
| static int lastIndexOf(char[] source, int sourceOffset, int sourceCount, |
| char[] target, int targetOffset, int targetCount, |
| int fromIndex) { |
| /* |
| * Check arguments; return immediately where possible. For |
| * consistency, don't check for null str. |
| */ |
| int rightIndex = sourceCount - targetCount; |
| if (fromIndex < 0) { |
| return -1; |
| } |
| if (fromIndex > rightIndex) { |
| fromIndex = rightIndex; |
| } |
| /* Empty string always matches. */ |
| if (targetCount == 0) { |
| return fromIndex; |
| } |
| |
| int strLastIndex = targetOffset + targetCount - 1; |
| char strLastChar = target[strLastIndex]; |
| int min = sourceOffset + targetCount - 1; |
| int i = min + fromIndex; |
| |
| startSearchForLastChar: |
| while (true) { |
| while (i >= min && source[i] != strLastChar) { |
| i--; |
| } |
| if (i < min) { |
| return -1; |
| } |
| int j = i - 1; |
| int start = j - (targetCount - 1); |
| int k = strLastIndex - 1; |
| |
| while (j > start) { |
| if (source[j--] != target[k--]) { |
| i--; |
| continue startSearchForLastChar; |
| } |
| } |
| return start - sourceOffset + 1; |
| } |
| } |
| |
| /** |
| * Returns a string that is a substring of this string. The |
| * substring begins with the character at the specified index and |
| * extends to the end of this string. <p> |
| * Examples: |
| * <blockquote><pre> |
| * "unhappy".substring(2) returns "happy" |
| * "Harbison".substring(3) returns "bison" |
| * "emptiness".substring(9) returns "" (an empty string) |
| * </pre></blockquote> |
| * |
| * @param beginIndex the beginning index, inclusive. |
| * @return the specified substring. |
| * @exception IndexOutOfBoundsException if |
| * {@code beginIndex} is negative or larger than the |
| * length of this {@code String} object. |
| */ |
| public String substring(int beginIndex) { |
| if (beginIndex < 0) { |
| throw new StringIndexOutOfBoundsException(this, beginIndex); |
| } |
| int subLen = count - beginIndex; |
| if (subLen < 0) { |
| throw new StringIndexOutOfBoundsException(this, beginIndex); |
| } |
| return (beginIndex == 0) ? this : fastSubstring(beginIndex, subLen); |
| } |
| |
| /** |
| * Returns a string that is a substring of this string. The |
| * substring begins at the specified {@code beginIndex} and |
| * extends to the character at index {@code endIndex - 1}. |
| * Thus the length of the substring is {@code endIndex-beginIndex}. |
| * <p> |
| * Examples: |
| * <blockquote><pre> |
| * "hamburger".substring(4, 8) returns "urge" |
| * "smiles".substring(1, 5) returns "mile" |
| * </pre></blockquote> |
| * |
| * @param beginIndex the beginning index, inclusive. |
| * @param endIndex the ending index, exclusive. |
| * @return the specified substring. |
| * @exception IndexOutOfBoundsException if the |
| * {@code beginIndex} is negative, or |
| * {@code endIndex} is larger than the length of |
| * this {@code String} object, or |
| * {@code beginIndex} is larger than |
| * {@code endIndex}. |
| */ |
| public String substring(int beginIndex, int endIndex) { |
| if (beginIndex < 0) { |
| throw new StringIndexOutOfBoundsException(this, beginIndex); |
| } |
| if (endIndex > count) { |
| throw new StringIndexOutOfBoundsException(this, endIndex); |
| } |
| int subLen = endIndex - beginIndex; |
| if (subLen < 0) { |
| throw new StringIndexOutOfBoundsException(subLen); |
| } |
| |
| return ((beginIndex == 0) && (endIndex == count)) ? this |
| : fastSubstring(beginIndex, subLen); |
| } |
| |
| private native String fastSubstring(int start, int length); |
| |
| /** |
| * Returns a character sequence that is a subsequence of this sequence. |
| * |
| * <p> An invocation of this method of the form |
| * |
| * <blockquote><pre> |
| * str.subSequence(begin, end)</pre></blockquote> |
| * |
| * behaves in exactly the same way as the invocation |
| * |
| * <blockquote><pre> |
| * str.substring(begin, end)</pre></blockquote> |
| * |
| * @apiNote |
| * This method is defined so that the {@code String} class can implement |
| * the {@link CharSequence} interface. |
| * |
| * @param beginIndex the begin index, inclusive. |
| * @param endIndex the end index, exclusive. |
| * @return the specified subsequence. |
| * |
| * @throws IndexOutOfBoundsException |
| * if {@code beginIndex} or {@code endIndex} is negative, |
| * if {@code endIndex} is greater than {@code length()}, |
| * or if {@code beginIndex} is greater than {@code endIndex} |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public CharSequence subSequence(int beginIndex, int endIndex) { |
| return this.substring(beginIndex, endIndex); |
| } |
| |
| /** |
| * Concatenates the specified string to the end of this string. |
| * <p> |
| * If the length of the argument string is {@code 0}, then this |
| * {@code String} object is returned. Otherwise, a |
| * {@code String} object is returned that represents a character |
| * sequence that is the concatenation of the character sequence |
| * represented by this {@code String} object and the character |
| * sequence represented by the argument string.<p> |
| * Examples: |
| * <blockquote><pre> |
| * "cares".concat("s") returns "caress" |
| * "to".concat("get").concat("her") returns "together" |
| * </pre></blockquote> |
| * |
| * @param str the {@code String} that is concatenated to the end |
| * of this {@code String}. |
| * @return a string that represents the concatenation of this object's |
| * characters followed by the string argument's characters. |
| */ |
| public native String concat(String str); |
| |
| /** |
| * Returns a string resulting from replacing all occurrences of |
| * {@code oldChar} in this string with {@code newChar}. |
| * <p> |
| * If the character {@code oldChar} does not occur in the |
| * character sequence represented by this {@code String} object, |
| * then a reference to this {@code String} object is returned. |
| * Otherwise, a {@code String} object is returned that |
| * represents a character sequence identical to the character sequence |
| * represented by this {@code String} object, except that every |
| * occurrence of {@code oldChar} is replaced by an occurrence |
| * of {@code newChar}. |
| * <p> |
| * Examples: |
| * <blockquote><pre> |
| * "mesquite in your cellar".replace('e', 'o') |
| * returns "mosquito in your collar" |
| * "the war of baronets".replace('r', 'y') |
| * returns "the way of bayonets" |
| * "sparring with a purple porpoise".replace('p', 't') |
| * returns "starring with a turtle tortoise" |
| * "JonL".replace('q', 'x') returns "JonL" (no change) |
| * </pre></blockquote> |
| * |
| * @param oldChar the old character. |
| * @param newChar the new character. |
| * @return a string derived from this string by replacing every |
| * occurrence of {@code oldChar} with {@code newChar}. |
| */ |
| public String replace(char oldChar, char newChar) { |
| String replaced = this; |
| if (oldChar != newChar) { |
| for (int i = 0; i < count; ++i) { |
| if (charAt(i) == oldChar) { |
| if (replaced == this) { |
| replaced = StringFactory.newStringFromString(this); |
| } |
| replaced.setCharAt(i, newChar); |
| } |
| } |
| } |
| return replaced; |
| } |
| |
| /** |
| * Tells whether or not this string matches the given <a |
| * href="../util/regex/Pattern.html#sum">regular expression</a>. |
| * |
| * <p> An invocation of this method of the form |
| * <i>str</i>{@code .matches(}<i>regex</i>{@code )} yields exactly the |
| * same result as the expression |
| * |
| * <blockquote> |
| * {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#matches(String,CharSequence) |
| * matches(<i>regex</i>, <i>str</i>)} |
| * </blockquote> |
| * |
| * @param regex |
| * the regular expression to which this string is to be matched |
| * |
| * @return {@code true} if, and only if, this string matches the |
| * given regular expression |
| * |
| * @throws PatternSyntaxException |
| * if the regular expression's syntax is invalid |
| * |
| * @see java.util.regex.Pattern |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public boolean matches(String regex) { |
| return Pattern.matches(regex, this); |
| } |
| |
| /** |
| * Returns true if and only if this string contains the specified |
| * sequence of char values. |
| * |
| * @param s the sequence to search for |
| * @return true if this string contains {@code s}, false otherwise |
| * @since 1.5 |
| */ |
| public boolean contains(CharSequence s) { |
| return indexOf(s.toString()) > -1; |
| } |
| |
| /** |
| * Replaces the first substring of this string that matches the given <a |
| * href="../util/regex/Pattern.html#sum">regular expression</a> with the |
| * given replacement. |
| * |
| * <p> An invocation of this method of the form |
| * <i>str</i>{@code .replaceFirst(}<i>regex</i>{@code ,} <i>repl</i>{@code )} |
| * yields exactly the same result as the expression |
| * |
| * <blockquote> |
| * <code> |
| * {@link java.util.regex.Pattern}.{@link |
| * java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
| * java.util.regex.Pattern#matcher(java.lang.CharSequence) matcher}(<i>str</i>).{@link |
| * java.util.regex.Matcher#replaceFirst replaceFirst}(<i>repl</i>) |
| * </code> |
| * </blockquote> |
| * |
| *<p> |
| * Note that backslashes ({@code \}) and dollar signs ({@code $}) in the |
| * replacement string may cause the results to be different than if it were |
| * being treated as a literal replacement string; see |
| * {@link java.util.regex.Matcher#replaceFirst}. |
| * Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special |
| * meaning of these characters, if desired. |
| * |
| * @param regex |
| * the regular expression to which this string is to be matched |
| * @param replacement |
| * the string to be substituted for the first match |
| * |
| * @return The resulting {@code String} |
| * |
| * @throws PatternSyntaxException |
| * if the regular expression's syntax is invalid |
| * |
| * @see java.util.regex.Pattern |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public String replaceFirst(String regex, String replacement) { |
| return Pattern.compile(regex).matcher(this).replaceFirst(replacement); |
| } |
| |
| /** |
| * Replaces each substring of this string that matches the given <a |
| * href="../util/regex/Pattern.html#sum">regular expression</a> with the |
| * given replacement. |
| * |
| * <p> An invocation of this method of the form |
| * <i>str</i>{@code .replaceAll(}<i>regex</i>{@code ,} <i>repl</i>{@code )} |
| * yields exactly the same result as the expression |
| * |
| * <blockquote> |
| * <code> |
| * {@link java.util.regex.Pattern}.{@link |
| * java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
| * java.util.regex.Pattern#matcher(java.lang.CharSequence) matcher}(<i>str</i>).{@link |
| * java.util.regex.Matcher#replaceAll replaceAll}(<i>repl</i>) |
| * </code> |
| * </blockquote> |
| * |
| *<p> |
| * Note that backslashes ({@code \}) and dollar signs ({@code $}) in the |
| * replacement string may cause the results to be different than if it were |
| * being treated as a literal replacement string; see |
| * {@link java.util.regex.Matcher#replaceAll Matcher.replaceAll}. |
| * Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special |
| * meaning of these characters, if desired. |
| * |
| * @param regex |
| * the regular expression to which this string is to be matched |
| * @param replacement |
| * the string to be substituted for each match |
| * |
| * @return The resulting {@code String} |
| * |
| * @throws PatternSyntaxException |
| * if the regular expression's syntax is invalid |
| * |
| * @see java.util.regex.Pattern |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public String replaceAll(String regex, String replacement) { |
| return Pattern.compile(regex).matcher(this).replaceAll(replacement); |
| } |
| |
| /** |
| * Replaces each substring of this string that matches the literal target |
| * sequence with the specified literal replacement sequence. The |
| * replacement proceeds from the beginning of the string to the end, for |
| * example, replacing "aa" with "b" in the string "aaa" will result in |
| * "ba" rather than "ab". |
| * |
| * @param target The sequence of char values to be replaced |
| * @param replacement The replacement sequence of char values |
| * @return The resulting string |
| * @throws NullPointerException if <code>target</code> or |
| * <code>replacement</code> is <code>null</code>. |
| * @since 1.5 |
| */ |
| public String replace(CharSequence target, CharSequence replacement) { |
| if (target == null) { |
| throw new NullPointerException("target == null"); |
| } |
| |
| if (replacement == null) { |
| throw new NullPointerException("replacement == null"); |
| } |
| |
| String replacementStr = replacement.toString(); |
| String targetStr = target.toString(); |
| |
| // Special case when target == "". This is a pretty nonsensical transformation and nobody |
| // should be hitting this. |
| // |
| // See commit 870b23b3febc85 and http://code.google.com/p/android/issues/detail?id=8807 |
| // An empty target is inserted at the start of the string, the end of the string and |
| // between all characters. |
| if (targetStr.isEmpty()) { |
| // Note that overallocates by |replacement.size()| if |this| is the empty string, but |
| // that should be a rare case within an already nonsensical case. |
| StringBuilder sb = new StringBuilder(replacementStr.length() * (count + 2) + count); |
| sb.append(replacementStr); |
| for (int i = 0; i < count; ++i) { |
| sb.append(charAt(i)); |
| sb.append(replacementStr); |
| } |
| |
| return sb.toString(); |
| } |
| |
| // This is the "regular" case. |
| int lastMatch = 0; |
| StringBuilder sb = null; |
| for (;;) { |
| int currentMatch = indexOf(this, targetStr, lastMatch); |
| if (currentMatch == -1) { |
| break; |
| } |
| |
| if (sb == null) { |
| sb = new StringBuilder(count); |
| } |
| |
| sb.append(this, lastMatch, currentMatch); |
| sb.append(replacementStr); |
| lastMatch = currentMatch + targetStr.count; |
| } |
| |
| if (sb != null) { |
| sb.append(this, lastMatch, count); |
| return sb.toString(); |
| } else { |
| return this; |
| } |
| } |
| |
| /** |
| * Splits this string around matches of the given |
| * <a href="../util/regex/Pattern.html#sum">regular expression</a>. |
| * |
| * <p> The array returned by this method contains each substring of this |
| * string that is terminated by another substring that matches the given |
| * expression or is terminated by the end of the string. The substrings in |
| * the array are in the order in which they occur in this string. If the |
| * expression does not match any part of the input then the resulting array |
| * has just one element, namely this string. |
| * |
| * <p> When there is a positive-width match at the beginning of this |
| * string then an empty leading substring is included at the beginning |
| * of the resulting array. A zero-width match at the beginning however |
| * never produces such empty leading substring. |
| * |
| * <p> The {@code limit} parameter controls the number of times the |
| * pattern is applied and therefore affects the length of the resulting |
| * array. If the limit <i>n</i> is greater than zero then the pattern |
| * will be applied at most <i>n</i> - 1 times, the array's |
| * length will be no greater than <i>n</i>, and the array's last entry |
| * will contain all input beyond the last matched delimiter. If <i>n</i> |
| * is non-positive then the pattern will be applied as many times as |
| * possible and the array can have any length. If <i>n</i> is zero then |
| * the pattern will be applied as many times as possible, the array can |
| * have any length, and trailing empty strings will be discarded. |
| * |
| * <p> The string {@code "boo:and:foo"}, for example, yields the |
| * following results with these parameters: |
| * |
| * <blockquote><table cellpadding=1 cellspacing=0 summary="Split example showing regex, limit, and result"> |
| * <tr> |
| * <th>Regex</th> |
| * <th>Limit</th> |
| * <th>Result</th> |
| * </tr> |
| * <tr><td align=center>:</td> |
| * <td align=center>2</td> |
| * <td>{@code { "boo", "and:foo" }}</td></tr> |
| * <tr><td align=center>:</td> |
| * <td align=center>5</td> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><td align=center>:</td> |
| * <td align=center>-2</td> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><td align=center>o</td> |
| * <td align=center>5</td> |
| * <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
| * <tr><td align=center>o</td> |
| * <td align=center>-2</td> |
| * <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
| * <tr><td align=center>o</td> |
| * <td align=center>0</td> |
| * <td>{@code { "b", "", ":and:f" }}</td></tr> |
| * </table></blockquote> |
| * |
| * <p> An invocation of this method of the form |
| * <i>str.</i>{@code split(}<i>regex</i>{@code ,} <i>n</i>{@code )} |
| * yields the same result as the expression |
| * |
| * <blockquote> |
| * <code> |
| * {@link java.util.regex.Pattern}.{@link |
| * java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
| * java.util.regex.Pattern#split(java.lang.CharSequence,int) split}(<i>str</i>, <i>n</i>) |
| * </code> |
| * </blockquote> |
| * |
| * |
| * @param regex |
| * the delimiting regular expression |
| * |
| * @param limit |
| * the result threshold, as described above |
| * |
| * @return the array of strings computed by splitting this string |
| * around matches of the given regular expression |
| * |
| * @throws PatternSyntaxException |
| * if the regular expression's syntax is invalid |
| * |
| * @see java.util.regex.Pattern |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public String[] split(String regex, int limit) { |
| // Try fast splitting without allocating Pattern object |
| String[] fast = Pattern.fastSplit(regex, this, limit); |
| if (fast != null) { |
| return fast; |
| } |
| |
| return Pattern.compile(regex).split(this, limit); |
| } |
| |
| /** |
| * Splits this string around matches of the given <a |
| * href="../util/regex/Pattern.html#sum">regular expression</a>. |
| * |
| * <p> This method works as if by invoking the two-argument {@link |
| * #split(String, int) split} method with the given expression and a limit |
| * argument of zero. Trailing empty strings are therefore not included in |
| * the resulting array. |
| * |
| * <p> The string {@code "boo:and:foo"}, for example, yields the following |
| * results with these expressions: |
| * |
| * <blockquote><table cellpadding=1 cellspacing=0 summary="Split examples showing regex and result"> |
| * <tr> |
| * <th>Regex</th> |
| * <th>Result</th> |
| * </tr> |
| * <tr><td align=center>:</td> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><td align=center>o</td> |
| * <td>{@code { "b", "", ":and:f" }}</td></tr> |
| * </table></blockquote> |
| * |
| * |
| * @param regex |
| * the delimiting regular expression |
| * |
| * @return the array of strings computed by splitting this string |
| * around matches of the given regular expression |
| * |
| * @throws PatternSyntaxException |
| * if the regular expression's syntax is invalid |
| * |
| * @see java.util.regex.Pattern |
| * |
| * @since 1.4 |
| * @spec JSR-51 |
| */ |
| public String[] split(String regex) { |
| return split(regex, 0); |
| } |
| |
| /** |
| * Returns a new String composed of copies of the |
| * {@code CharSequence elements} joined together with a copy of |
| * the specified {@code delimiter}. |
| * |
| * <blockquote>For example, |
| * <pre>{@code |
| * String message = String.join("-", "Java", "is", "cool"); |
| * // message returned is: "Java-is-cool" |
| * }</pre></blockquote> |
| * |
| * Note that if an element is null, then {@code "null"} is added. |
| * |
| * @param delimiter the delimiter that separates each element |
| * @param elements the elements to join together. |
| * |
| * @return a new {@code String} that is composed of the {@code elements} |
| * separated by the {@code delimiter} |
| * |
| * @throws NullPointerException If {@code delimiter} or {@code elements} |
| * is {@code null} |
| * |
| * @see java.util.StringJoiner |
| * @since 1.8 |
| */ |
| public static String join(CharSequence delimiter, CharSequence... elements) { |
| Objects.requireNonNull(delimiter); |
| Objects.requireNonNull(elements); |
| // Number of elements not likely worth Arrays.stream overhead. |
| StringJoiner joiner = new StringJoiner(delimiter); |
| for (CharSequence cs: elements) { |
| joiner.add(cs); |
| } |
| return joiner.toString(); |
| } |
| |
| /** |
| * Returns a new {@code String} composed of copies of the |
| * {@code CharSequence elements} joined together with a copy of the |
| * specified {@code delimiter}. |
| * |
| * <blockquote>For example, |
| * <pre>{@code |
| * List<String> strings = new LinkedList<>(); |
| * strings.add("Java");strings.add("is"); |
| * strings.add("cool"); |
| * String message = String.join(" ", strings); |
| * //message returned is: "Java is cool" |
| * |
| * Set<String> strings = new LinkedHashSet<>(); |
| * strings.add("Java"); strings.add("is"); |
| * strings.add("very"); strings.add("cool"); |
| * String message = String.join("-", strings); |
| * //message returned is: "Java-is-very-cool" |
| * }</pre></blockquote> |
| * |
| * Note that if an individual element is {@code null}, then {@code "null"} is added. |
| * |
| * @param delimiter a sequence of characters that is used to separate each |
| * of the {@code elements} in the resulting {@code String} |
| * @param elements an {@code Iterable} that will have its {@code elements} |
| * joined together. |
| * |
| * @return a new {@code String} that is composed from the {@code elements} |
| * argument |
| * |
| * @throws NullPointerException If {@code delimiter} or {@code elements} |
| * is {@code null} |
| * |
| * @see #join(CharSequence,CharSequence...) |
| * @see java.util.StringJoiner |
| * @since 1.8 |
| */ |
| public static String join(CharSequence delimiter, |
| Iterable<? extends CharSequence> elements) { |
| Objects.requireNonNull(delimiter); |
| Objects.requireNonNull(elements); |
| StringJoiner joiner = new StringJoiner(delimiter); |
| for (CharSequence cs: elements) { |
| joiner.add(cs); |
| } |
| return joiner.toString(); |
| } |
| |
| /** |
| * Converts all of the characters in this {@code String} to lower |
| * case using the rules of the given {@code Locale}. Case mapping is based |
| * on the Unicode Standard version specified by the {@link java.lang.Character Character} |
| * class. Since case mappings are not always 1:1 char mappings, the resulting |
| * {@code String} may be a different length than the original {@code String}. |
| * <p> |
| * Examples of lowercase mappings are in the following table: |
| * <table border="1" summary="Lowercase mapping examples showing language code of locale, upper case, lower case, and description"> |
| * <tr> |
| * <th>Language Code of Locale</th> |
| * <th>Upper Case</th> |
| * <th>Lower Case</th> |
| * <th>Description</th> |
| * </tr> |
| * <tr> |
| * <td>tr (Turkish)</td> |
| * <td>\u0130</td> |
| * <td>\u0069</td> |
| * <td>capital letter I with dot above -> small letter i</td> |
| * </tr> |
| * <tr> |
| * <td>tr (Turkish)</td> |
| * <td>\u0049</td> |
| * <td>\u0131</td> |
| * <td>capital letter I -> small letter dotless i </td> |
| * </tr> |
| * <tr> |
| * <td>(all)</td> |
| * <td>French Fries</td> |
| * <td>french fries</td> |
| * <td>lowercased all chars in String</td> |
| * </tr> |
| * <tr> |
| * <td>(all)</td> |
| * <td><img src="doc-files/capiota.gif" alt="capiota"><img src="doc-files/capchi.gif" alt="capchi"> |
| * <img src="doc-files/captheta.gif" alt="captheta"><img src="doc-files/capupsil.gif" alt="capupsil"> |
| * <img src="doc-files/capsigma.gif" alt="capsigma"></td> |
| * <td><img src="doc-files/iota.gif" alt="iota"><img src="doc-files/chi.gif" alt="chi"> |
| * <img src="doc-files/theta.gif" alt="theta"><img src="doc-files/upsilon.gif" alt="upsilon"> |
| * <img src="doc-files/sigma1.gif" alt="sigma"></td> |
| * <td>lowercased all chars in String</td> |
| * </tr> |
| * </table> |
| * |
| * @param locale use the case transformation rules for this locale |
| * @return the {@code String}, converted to lowercase. |
| * @see java.lang.String#toLowerCase() |
| * @see java.lang.String#toUpperCase() |
| * @see java.lang.String#toUpperCase(Locale) |
| * @since 1.1 |
| */ |
| public String toLowerCase(Locale locale) { |
| return CaseMapper.toLowerCase(locale, this); |
| } |
| |
| /** |
| * Converts all of the characters in this {@code String} to lower |
| * case using the rules of the default locale. This is equivalent to calling |
| * {@code toLowerCase(Locale.getDefault())}. |
| * <p> |
| * <b>Note:</b> This method is locale sensitive, and may produce unexpected |
| * results if used for strings that are intended to be interpreted locale |
| * independently. |
| * Examples are programming language identifiers, protocol keys, and HTML |
| * tags. |
| * For instance, {@code "TITLE".toLowerCase()} in a Turkish locale |
| * returns {@code "t\u005Cu0131tle"}, where '\u005Cu0131' is the |
| * LATIN SMALL LETTER DOTLESS I character. |
| * To obtain correct results for locale insensitive strings, use |
| * {@code toLowerCase(Locale.ROOT)}. |
| * <p> |
| * @return the {@code String}, converted to lowercase. |
| * @see java.lang.String#toLowerCase(Locale) |
| */ |
| public String toLowerCase() { |
| return toLowerCase(Locale.getDefault()); |
| } |
| |
| /** |
| * Converts all of the characters in this {@code String} to upper |
| * case using the rules of the given {@code Locale}. Case mapping is based |
| * on the Unicode Standard version specified by the {@link java.lang.Character Character} |
| * class. Since case mappings are not always 1:1 char mappings, the resulting |
| * {@code String} may be a different length than the original {@code String}. |
| * <p> |
| * Examples of locale-sensitive and 1:M case mappings are in the following table. |
| * |
| * <table border="1" summary="Examples of locale-sensitive and 1:M case mappings. Shows Language code of locale, lower case, upper case, and description."> |
| * <tr> |
| * <th>Language Code of Locale</th> |
| * <th>Lower Case</th> |
| * <th>Upper Case</th> |
| * <th>Description</th> |
| * </tr> |
| * <tr> |
| * <td>tr (Turkish)</td> |
| * <td>\u0069</td> |
| * <td>\u0130</td> |
| * <td>small letter i -> capital letter I with dot above</td> |
| * </tr> |
| * <tr> |
| * <td>tr (Turkish)</td> |
| * <td>\u0131</td> |
| * <td>\u0049</td> |
| * <td>small letter dotless i -> capital letter I</td> |
| * </tr> |
| * <tr> |
| * <td>(all)</td> |
| * <td>\u00df</td> |
| * <td>\u0053 \u0053</td> |
| * <td>small letter sharp s -> two letters: SS</td> |
| * </tr> |
| * <tr> |
| * <td>(all)</td> |
| * <td>Fahrvergnügen</td> |
| * <td>FAHRVERGNÜGEN</td> |
| * <td></td> |
| * </tr> |
| * </table> |
| * @param locale use the case transformation rules for this locale |
| * @return the {@code String}, converted to uppercase. |
| * @see java.lang.String#toUpperCase() |
| * @see java.lang.String#toLowerCase() |
| * @see java.lang.String#toLowerCase(Locale) |
| * @since 1.1 |
| */ |
| public String toUpperCase(Locale locale) { |
| return CaseMapper.toUpperCase(locale, this, count); |
| } |
| |
| /** |
| * Converts all of the characters in this {@code String} to upper |
| * case using the rules of the default locale. This method is equivalent to |
| * {@code toUpperCase(Locale.getDefault())}. |
| * <p> |
| * <b>Note:</b> This method is locale sensitive, and may produce unexpected |
| * results if used for strings that are intended to be interpreted locale |
| * independently. |
| * Examples are programming language identifiers, protocol keys, and HTML |
| * tags. |
| * For instance, {@code "title".toUpperCase()} in a Turkish locale |
| * returns {@code "T\u005Cu0130TLE"}, where '\u005Cu0130' is the |
| * LATIN CAPITAL LETTER I WITH DOT ABOVE character. |
| * To obtain correct results for locale insensitive strings, use |
| * {@code toUpperCase(Locale.ROOT)}. |
| * <p> |
| * @return the {@code String}, converted to uppercase. |
| * @see java.lang.String#toUpperCase(Locale) |
| */ |
| public String toUpperCase() { |
| return toUpperCase(Locale.getDefault()); |
| } |
| |
| /** |
| * Returns a string whose value is this string, with any leading and trailing |
| * whitespace removed. |
| * <p> |
| * If this {@code String} object represents an empty character |
| * sequence, or the first and last characters of character sequence |
| * represented by this {@code String} object both have codes |
| * greater than {@code '\u005Cu0020'} (the space character), then a |
| * reference to this {@code String} object is returned. |
| * <p> |
| * Otherwise, if there is no character with a code greater than |
| * {@code '\u005Cu0020'} in the string, then a |
| * {@code String} object representing an empty string is |
| * returned. |
| * <p> |
| * Otherwise, let <i>k</i> be the index of the first character in the |
| * string whose code is greater than {@code '\u005Cu0020'}, and let |
| * <i>m</i> be the index of the last character in the string whose code |
| * is greater than {@code '\u005Cu0020'}. A {@code String} |
| * object is returned, representing the substring of this string that |
| * begins with the character at index <i>k</i> and ends with the |
| * character at index <i>m</i>-that is, the result of |
| * {@code this.substring(k, m + 1)}. |
| * <p> |
| * This method may be used to trim whitespace (as defined above) from |
| * the beginning and end of a string. |
| * |
| * @return A string whose value is this string, with any leading and trailing white |
| * space removed, or this string if it has no leading or |
| * trailing white space. |
| */ |
| public String trim() { |
| int len = count; |
| int st = 0; |
| |
| while ((st < len) && (charAt(st) <= ' ')) { |
| st++; |
| } |
| while ((st < len) && (charAt(len - 1) <= ' ')) { |
| len--; |
| } |
| return ((st > 0) || (len < count)) ? substring(st, len) : this; |
| } |
| |
| /** |
| * This object (which is already a string!) is itself returned. |
| * |
| * @return the string itself. |
| */ |
| public String toString() { |
| return this; |
| } |
| |
| /** |
| * Converts this string to a new character array. |
| * |
| * @return a newly allocated character array whose length is the length |
| * of this string and whose contents are initialized to contain |
| * the character sequence represented by this string. |
| */ |
| public native char[] toCharArray(); |
| |
| |
| /** |
| * Returns a formatted string using the specified format string and |
| * arguments. |
| * |
| * <p> The locale always used is the one returned by {@link |
| * java.util.Locale#getDefault() Locale.getDefault()}. |
| * |
| * @param format |
| * A <a href="../util/Formatter.html#syntax">format string</a> |
| * |
| * @param args |
| * Arguments referenced by the format specifiers in the format |
| * string. If there are more arguments than format specifiers, the |
| * extra arguments are ignored. The number of arguments is |
| * variable and may be zero. The maximum number of arguments is |
| * limited by the maximum dimension of a Java array as defined by |
| * <cite>The Java™ Virtual Machine Specification</cite>. |
| * The behaviour on a |
| * {@code null} argument depends on the <a |
| * href="../util/Formatter.html#syntax">conversion</a>. |
| * |
| * @throws java.util.IllegalFormatException |
| * If a format string contains an illegal syntax, a format |
| * specifier that is incompatible with the given arguments, |
| * insufficient arguments given the format string, or other |
| * illegal conditions. For specification of all possible |
| * formatting errors, see the <a |
| * href="../util/Formatter.html#detail">Details</a> section of the |
| * formatter class specification. |
| * |
| * @throws NullPointerException |
| * If the <tt>format</tt> is <tt>null</tt> |
| * |
| * @return A formatted string |
| * |
| * @see java.util.Formatter |
| * @since 1.5 |
| */ |
| public static String format(String format, Object... args) { |
| return new Formatter().format(format, args).toString(); |
| } |
| |
| /** |
| * Returns a formatted string using the specified locale, format string, |
| * and arguments. |
| * |
| * @param l |
| * The {@linkplain java.util.Locale locale} to apply during |
| * formatting. If {@code l} is {@code null} then no localization |
| * is applied. |
| * |
| * @param format |
| * A <a href="../util/Formatter.html#syntax">format string</a> |
| * |
| * @param args |
| * Arguments referenced by the format specifiers in the format |
| * string. If there are more arguments than format specifiers, the |
| * extra arguments are ignored. The number of arguments is |
| * variable and may be zero. The maximum number of arguments is |
| * limited by the maximum dimension of a Java array as defined by |
| * <cite>The Java™ Virtual Machine Specification</cite>. |
| * The behaviour on a |
| * {@code null} argument depends on the |
| * <a href="../util/Formatter.html#syntax">conversion</a>. |
| * |
| * @throws java.util.IllegalFormatException |
| * If a format string contains an illegal syntax, a format |
| * specifier that is incompatible with the given arguments, |
| * insufficient arguments given the format string, or other |
| * illegal conditions. For specification of all possible |
| * formatting errors, see the <a |
| * href="../util/Formatter.html#detail">Details</a> section of the |
| * formatter class specification |
| * |
| * @throws NullPointerException |
| * If the <tt>format</tt> is <tt>null</tt> |
| * |
| * @return A formatted string |
| * |
| * @see java.util.Formatter |
| * @since 1.5 |
| */ |
| public static String format(Locale l, String format, Object... args) { |
| return new Formatter(l).format(format, args).toString(); |
| } |
| |
| /** |
| * Returns the string representation of the {@code Object} argument. |
| * |
| * @param obj an {@code Object}. |
| * @return if the argument is {@code null}, then a string equal to |
| * {@code "null"}; otherwise, the value of |
| * {@code obj.toString()} is returned. |
| * @see java.lang.Object#toString() |
| */ |
| public static String valueOf(Object obj) { |
| return (obj == null) ? "null" : obj.toString(); |
| } |
| |
| /** |
| * Returns the string representation of the {@code char} array |
| * argument. The contents of the character array are copied; subsequent |
| * modification of the character array does not affect the returned |
| * string. |
| * |
| * @param data the character array. |
| * @return a {@code String} that contains the characters of the |
| * character array. |
| */ |
| public static String valueOf(char data[]) { |
| return StringFactory.newStringFromChars(data); |
| } |
| |
| /** |
| * Returns the string representation of a specific subarray of the |
| * {@code char} array argument. |
| * <p> |
| * The {@code offset} argument is the index of the first |
| * character of the subarray. The {@code count} argument |
| * specifies the length of the subarray. The contents of the subarray |
| * are copied; subsequent modification of the character array does not |
| * affect the returned string. |
| * |
| * @param data the character array. |
| * @param offset initial offset of the subarray. |
| * @param count length of the subarray. |
| * @return a {@code String} that contains the characters of the |
| * specified subarray of the character array. |
| * @exception IndexOutOfBoundsException if {@code offset} is |
| * negative, or {@code count} is negative, or |
| * {@code offset+count} is larger than |
| * {@code data.length}. |
| */ |
| public static String valueOf(char data[], int offset, int count) { |
| return StringFactory.newStringFromChars(data, offset, count); |
| } |
| |
| /** |
| * Equivalent to {@link #valueOf(char[], int, int)}. |
| * |
| * @param data the character array. |
| * @param offset initial offset of the subarray. |
| * @param count length of the subarray. |
| * @return a {@code String} that contains the characters of the |
| * specified subarray of the character array. |
| * @exception IndexOutOfBoundsException if {@code offset} is |
| * negative, or {@code count} is negative, or |
| * {@code offset+count} is larger than |
| * {@code data.length}. |
| */ |
| public static String copyValueOf(char data[], int offset, int count) { |
| // All public String constructors now copy the data. |
| return StringFactory.newStringFromChars(data, offset, count); |
| } |
| |
| /** |
| * Equivalent to {@link #valueOf(char[])}. |
| * |
| * @param data the character array. |
| * @return a {@code String} that contains the characters of the |
| * character array. |
| */ |
| public static String copyValueOf(char data[]) { |
| return StringFactory.newStringFromChars(data); |
| } |
| |
| /** |
| * Returns the string representation of the {@code boolean} argument. |
| * |
| * @param b a {@code boolean}. |
| * @return if the argument is {@code true}, a string equal to |
| * {@code "true"} is returned; otherwise, a string equal to |
| * {@code "false"} is returned. |
| */ |
| public static String valueOf(boolean b) { |
| return b ? "true" : "false"; |
| } |
| |
| /** |
| * Returns the string representation of the {@code char} |
| * argument. |
| * |
| * @param c a {@code char}. |
| * @return a string of length {@code 1} containing |
| * as its single character the argument {@code c}. |
| */ |
| public static String valueOf(char c) { |
| return StringFactory.newStringFromChars(0, 1, new char[] { c }); |
| } |
| |
| /** |
| * Returns the string representation of the {@code int} argument. |
| * <p> |
| * The representation is exactly the one returned by the |
| * {@code Integer.toString} method of one argument. |
| * |
| * @param i an {@code int}. |
| * @return a string representation of the {@code int} argument. |
| * @see java.lang.Integer#toString(int, int) |
| */ |
| public static String valueOf(int i) { |
| return Integer.toString(i); |
| } |
| |
| /** |
| * Returns the string representation of the {@code long} argument. |
| * <p> |
| * The representation is exactly the one returned by the |
| * {@code Long.toString} method of one argument. |
| * |
| * @param l a {@code long}. |
| * @return a string representation of the {@code long} argument. |
| * @see java.lang.Long#toString(long) |
| */ |
| public static String valueOf(long l) { |
| return Long.toString(l); |
| } |
| |
| /** |
| * Returns the string representation of the {@code float} argument. |
| * <p> |
| * The representation is exactly the one returned by the |
| * {@code Float.toString} method of one argument. |
| * |
| * @param f a {@code float}. |
| * @return a string representation of the {@code float} argument. |
| * @see java.lang.Float#toString(float) |
| */ |
| public static String valueOf(float f) { |
| return Float.toString(f); |
| } |
| |
| /** |
| * Returns the string representation of the {@code double} argument. |
| * <p> |
| * The representation is exactly the one returned by the |
| * {@code Double.toString} method of one argument. |
| * |
| * @param d a {@code double}. |
| * @return a string representation of the {@code double} argument. |
| * @see java.lang.Double#toString(double) |
| */ |
| public static String valueOf(double d) { |
| return Double.toString(d); |
| } |
| |
| /** |
| * Returns a canonical representation for the string object. |
| * <p> |
| * A pool of strings, initially empty, is maintained privately by the |
| * class {@code String}. |
| * <p> |
| * When the intern method is invoked, if the pool already contains a |
| * string equal to this {@code String} object as determined by |
| * the {@link #equals(Object)} method, then the string from the pool is |
| * returned. Otherwise, this {@code String} object is added to the |
| * pool and a reference to this {@code String} object is returned. |
| * <p> |
| * It follows that for any two strings {@code s} and {@code t}, |
| * {@code s.intern() == t.intern()} is {@code true} |
| * if and only if {@code s.equals(t)} is {@code true}. |
| * <p> |
| * All literal strings and string-valued constant expressions are |
| * interned. String literals are defined in section 3.10.5 of the |
| * <cite>The Java™ Language Specification</cite>. |
| * |
| * @return a string that has the same contents as this string, but is |
| * guaranteed to be from a pool of unique strings. |
| */ |
| public native String intern(); |
| } |