String类

/* * @(#)String.java 1.204 06/06/09 * * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package java.lang; import java.io.ObjectStreamClass; import java.io.ObjectStreamField; import java.io.UnsupportedEncodingException; 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.regex.Matcher; import java.util.regex.Pattern; import java.util.regex.PatternSyntaxException; /** * The <code>String</code> class represents character strings. All * string literals in Java programs, such as <code>"abc"</code>, 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: * <p><blockquote><pre> * String str = "abc"; * </pre></blockquote><p> * is equivalent to: * <p><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: * <p><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</code> 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</code>(or <code>StringBuffer</code>) * class and its <code>append</code> method. * String conversions are implemented through the method * <code>toString</code>, defined by <code>Object</code> 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</code> 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" mce_href="Character.html#unicode">Unicode * Character Representations</a> in the <code>Character</code> class for * more information). * Index values refer to <code>char</code> code units, so a supplementary * character uses two positions in a <code>String</code>. * <p>The <code>String</code> 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</code> values). * * @author Lee Boynton * @author Arthur van Hoff * @version 1.204, 06/09/06 * @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 { /** The value is used for character storage. */ private final char value[]; /** The offset is the first index of the storage that is used. */ private final int offset; /** The count is the number of characters in the String. */ 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 initially into an ObjectOutputStream in the * following format: * <pre> * <code>TC_STRING</code> (utf String) * </pre> * The String is written by method <code>DataOutput.writeUTF</code>. * A new handle is generated to refer to all future references to the * string instance within the stream. */ 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() { this.offset = 0; this.count = 0; this.value = new char[0]; } /** * 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) { int size = original.count; char[] originalValue = original.value; char[] v; if (originalValue.length > size) { // The array representing the String is bigger than the new // String itself. Perhaps this constructor is being called // in order to trim the baggage, so make a copy of the array. int off = original.offset; v = Arrays.copyOfRange(originalValue, off, off+size); } else { // The array representing the String is the same // size as the String, so no point in making a copy. v = originalValue; } this.offset = 0; this.count = size; this.value = v; } /** * 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[]) { int size = value.length; this.offset = 0; this.count = size; this.value = Arrays.copyOf(value, size); } /** * 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) { if (offset < 0) { throw new StringIndexOutOfBoundsException(offset); } if (count < 0) { throw new StringIndexOutOfBoundsException(count); } // Note: offset or count might be near -1>>>1. if (offset > value.length - count) { throw new StringIndexOutOfBoundsException(offset + count); } this.offset = 0; this.count = count; this.value = Arrays.copyOfRange(value, offset, offset+count); } /** * Allocates a new {@code String} that contains characters from a subarray * of the Unicode code point 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) { if (offset < 0) { throw new StringIndexOutOfBoundsException(offset); } if (count < 0) { throw new StringIndexOutOfBoundsException(count); } // Note: offset or count might be near -1>>>1. if (offset > codePoints.length - count) { throw new StringIndexOutOfBoundsException(offset + count); } int expansion = 0; int margin = 1; char[] v = new char[count + margin]; int x = offset; int j = 0; for (int i = 0; i < count; i++) { int c = codePoints[x++]; if (c < 0) { throw new IllegalArgumentException(); } if (margin <= 0 && (j+1) >= v.length) { if (expansion == 0) { expansion = (((-margin + 1) * count) << 10) / i; expansion >>= 10; if (expansion <= 0) { expansion = 1; } } else { expansion *= 2; } int newLen = Math.min(v.length+expansion, count*2); margin = (newLen - v.length) - (count - i); v = Arrays.copyOf(v, newLen); } if (c < Character.MIN_SUPPLEMENTARY_CODE_POINT) { v[j++] = (char) c; } else if (c <= Character.MAX_CODE_POINT) { Character.toSurrogates(c, v, j); j += 2; margin--; } else { throw new IllegalArgumentException(); } } this.offset = 0; this.value = v; this.count = j; } /** * 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) { checkBounds(ascii, offset, count); char value[] = new char[count]; if (hibyte == 0) { for (int i = count ; i-- > 0 ;) { value[i] = (char) (ascii[i + offset] & 0xff); } } else { hibyte <<= 8; for (int i = count ; i-- > 0 ;) { value[i] = (char) (hibyte | (ascii[i + offset] & 0xff)); } } this.offset = 0; this.count = count; this.value = value; } /** * 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) { this(ascii, hibyte, 0, ascii.length); } /* Common private utility method used to bounds check the byte array * and requested offset & length values used by the String(byte[],..) * constructors. */ private static void checkBounds(byte[] bytes, int offset, int length) { if (length < 0) throw new StringIndexOutOfBoundsException(length); if (offset < 0) throw new StringIndexOutOfBoundsException(offset); if (offset > bytes.length - length) throw new StringIndexOutOfBoundsException(offset + length); } /** * 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 { if (charsetName == null) throw new NullPointerException("charsetName"); checkBounds(bytes, offset, length); char[] v = StringCoding.decode(charsetName, bytes, offset, length); this.offset = 0; this.count = v.length; this.value = v; } /** * 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) { if (charset == null) throw new NullPointerException("charset"); checkBounds(bytes, offset, length); char[] v = StringCoding.decode(charset, bytes, offset, length); this.offset = 0; this.count = v.length; this.value = v; } /** * 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 { this(bytes, 0, bytes.length, charsetName); } /** * 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) { this(bytes, 0, bytes.length, charset); } /** * 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) { checkBounds(bytes, offset, length); char[] v = StringCoding.decode(bytes, offset, length); this.offset = 0; this.count = v.length; this.value = v; } /** * 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[]) { this(bytes, 0, bytes.length); } /** * 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) { String result = buffer.toString(); this.value = result.value; this.count = result.count; this.offset = result.offset; } /** * 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) { String result = builder.toString(); this.value = result.value; this.count = result.count; this.offset = result.offset; } // Package private constructor which shares value array for speed. String(int offset, int count, char value[]) { this.value = value; this.offset = offset; this.count = count; } /** * Returns the length of this string. * The length is equal to the number of <a href="Character.html#unicode" mce_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 <tt>true</tt> if, and only if, {@link #length()} is <tt>0</tt>. * * @return <tt>true</tt> if {@link #length()} is <tt>0</tt>, otherwise * <tt>false</tt> * * @since 1.6 */ public boolean isEmpty() { return count == 0; } /** * Returns the <code>char</code> value at the * specified index. An index ranges from <code>0</code> to * <code>length() - 1</code>. The first <code>char</code> value of the sequence * is at index <code>0</code>, the next at index <code>1</code>, * and so on, as for array indexing. * * <p>If the <code>char</code> value specified by the index is a * <a href="Character.html#unicode" mce_href="Character.html#unicode">surrogate</a>, the surrogate * value is returned. * * @param index the index of the <code>char</code> value. * @return the <code>char</code> value at the specified index of this string. * The first <code>char</code> value is at index <code>0</code>. * @exception IndexOutOfBoundsException if the <code>index</code> * argument is negative or not less than the length of this * string. */ public char charAt(int index) { if ((index < 0) || (index >= count)) { throw new StringIndexOutOfBoundsException(index); } return value[index + offset]; } /** * Returns the character (Unicode code point) at the specified * index. The index refers to <code>char</code> values * (Unicode code units) and ranges from <code>0</code> to * {@link #length()}<code> - 1</code>. * * <p> If the <code>char</code> value specified at the given index * is in the high-surrogate range, the following index is less * than the length of this <code>String</code>, and the * <code>char</code> 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</code> value at the given index is returned. * * @param index the index to the <code>char</code> values * @return the code point value of the character at the * <code>index</code> * @exception IndexOutOfBoundsException if the <code>index</code> * 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.codePointAtImpl(value, offset + index, offset + count); } /** * Returns the character (Unicode code point) before the specified * index. The index refers to <code>char</code> values * (Unicode code units) and ranges from <code>1</code> to {@link * CharSequence#length() length}. * * <p> If the <code>char</code> value at <code>(index - 1)</code> * is in the low-surrogate range, <code>(index - 2)</code> is not * negative, and the <code>char</code> value at <code>(index - * 2)</code> is in the high-surrogate range, then the * supplementary code point value of the surrogate pair is * returned. If the <code>char</code> value at <code>index - * 1</code> 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</code> * 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.codePointBeforeImpl(value, offset + index, offset); } /** * Returns the number of Unicode code points in the specified text * range of this <code>String</code>. The text range begins at the * specified <code>beginIndex</code> and extends to the * <code>char</code> at index <code>endIndex - 1</code>. Thus the * length (in <code>char</code>s) of the text range is * <code>endIndex-beginIndex</code>. Unpaired surrogates within * the text range count as one code point each. * * @param beginIndex the index to the first <code>char</code> of * the text range. * @param endIndex the index after the last <code>char</code> of * the text range. * @return the number of Unicode code points in the specified text * range * @exception IndexOutOfBoundsException if the * <code>beginIndex</code> is negative, or <code>endIndex</code> * is larger than the length of this <code>String</code>, or * <code>beginIndex</code> is larger than <code>endIndex</code>. * @since 1.5 */ public int codePointCount(int beginIndex, int endIndex) { if (beginIndex < 0 || endIndex > count || beginIndex > endIndex) { throw new IndexOutOfBoundsException(); } return Character.codePointCountImpl(value, offset+beginIndex, endIndex-beginIndex); } /** * Returns the index within this <code>String</code> that is * offset from the given <code>index</code> by * <code>codePointOffset</code> code points. Unpaired surrogates * within the text range given by <code>index</code> and * <code>codePointOffset</code> 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</code> * @exception IndexOutOfBoundsException if <code>index</code> * is negative or larger then the length of this * <code>String</code>, or if <code>codePointOffset</code> is positive * and the substring starting with <code>index</code> has fewer * than <code>codePointOffset</code> code points, * or if <code>codePointOffset</code> is negative and the substring * before <code>index</code> has fewer than the absolute value * of <code>codePointOffset</code> code points. * @since 1.5 */ public int offsetByCodePoints(int index, int codePointOffset) { if (index < 0 || index > count) { throw new IndexOutOfBoundsException(); } return Character.offsetByCodePointsImpl(value, offset, count, offset+index, codePointOffset) - offset; } /** * Copy characters from this string into dst starting at dstBegin. * This method doesn't perform any range checking. */ void getChars(char dst[], int dstBegin) { System.arraycopy(value, offset, dst, dstBegin, count); } /** * Copies characters from this string into the destination character * array. * <p> * The first character to be copied is at index <code>srcBegin</code>; * the last character to be copied is at index <code>srcEnd-1</code> * (thus the total number of characters to be copied is * <code>srcEnd-srcBegin</code>). The characters are copied into the * subarray of <code>dst</code> starting at index <code>dstBegin</code> * and ending at index: * <p><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</code> is negative. * <li><code>srcBegin</code> is greater than <code>srcEnd</code> * <li><code>srcEnd</code> is greater than the length of this * string * <li><code>dstBegin</code> is negative * <li><code>dstBegin+(srcEnd-srcBegin)</code> is larger than * <code>dst.length</code></ul> */ public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) { if (srcBegin < 0) { throw new StringIndexOutOfBoundsException(srcBegin); } if (srcEnd > count) { throw new StringIndexOutOfBoundsException(srcEnd); } if (srcBegin > srcEnd) { throw new StringIndexOutOfBoundsException(srcEnd - srcBegin); } System.arraycopy(value, offset + srcBegin, dst, dstBegin, srcEnd - srcBegin); } /** * 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(srcBegin); } if (srcEnd > count) { throw new StringIndexOutOfBoundsException(srcEnd); } if (srcBegin > srcEnd) { throw new StringIndexOutOfBoundsException(srcEnd - srcBegin); } int j = dstBegin; int n = offset + srcEnd; int i = offset + srcBegin; char[] val = value; /* avoid getfield opcode */ while (i < n) { dst[j++] = (byte)val[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 StringCoding.encode(charsetName, value, offset, count); } /** * 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(); return StringCoding.encode(charset, value, offset, count); } /** * 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 StringCoding.encode(value, offset, count); } /** * 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) { char v1[] = value; char v2[] = anotherString.value; int i = offset; int j = anotherString.offset; while (n-- != 0) { if (v1[i++] != v2[j++]) return false; } 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}. * * @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) { synchronized(sb) { return contentEquals((CharSequence)sb); } } /** * 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. * * @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) { if (count != cs.length()) return false; // Argument is a StringBuffer, StringBuilder if (cs instanceof AbstractStringBuilder) { char v1[] = value; char v2[] = ((AbstractStringBuilder)cs).getValue(); int i = offset; int j = 0; int n = count; while (n-- != 0) { if (v1[i++] != v2[j++]) return false; } } // Argument is a String if (cs.equals(this)) return true; // Argument is a generic CharSequence char v1[] = value; int i = offset; int j = 0; int n = count; while (n-- != 0) { if (v1[i++] != cs.charAt(j++)) 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</code> object is compared lexicographically to the * character sequence represented by the argument string. The result is * a negative integer if this <code>String</code> object * lexicographically precedes the argument string. The result is a * positive integer if this <code>String</code> object lexicographically * follows the argument string. The result is zero if the strings * are equal; <code>compareTo</code> returns <code>0</code> exactly when * the {@link #equals(Object)} method would return <code>true</code>. * <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</code> returns the * difference of the two character values at position <code>k</code> 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</code> 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</code> to be compared. * @return the value <code>0</code> if the argument string is equal to * this string; a value less than <code>0</code> if this string * is lexicographically less than the string argument; and a * value greater than <code>0</code> if this string is * lexicographically greater than the string argument. */ public int compareTo(String anotherString) { int len1 = count; int len2 = anotherString.count; int n = Math.min(len1, len2); char v1[] = value; char v2[] = anotherString.value; int i = offset; int j = anotherString.offset; if (i == j) { int k = i; int lim = n + i; while (k < lim) { char c1 = v1[k]; char c2 = v2[k]; if (c1 != c2) { return c1 - c2; } k++; } } else { while (n-- != 0) { char c1 = v1[i++]; char c2 = v2[j++]; if (c1 != c2) { return c1 - c2; } } } return len1 - len2; } /** * A Comparator that orders <code>String</code> objects as by * <code>compareToIgnoreCase</code>. 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(), n2=s2.length(); for (int i1=0, i2=0; i1<n1 && i2<n2; i1++, i2++) { char c1 = s1.charAt(i1); char c2 = s2.charAt(i2); 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) { return c1 - c2; } } } } return n1 - n2; } } /** * Compares two strings lexicographically, ignoring case * differences. This method returns an integer whose sign is that of * calling <code>compareTo</code> with normalized versions of the strings * where case differences have been eliminated by calling * <code>Character.toLowerCase(Character.toUpperCase(character))</code> 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</code> 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 <tt>String</tt> 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 * <tt>String</tt> object to be compared begins at index <tt>toffset</tt> * and has length <tt>len</tt>. The substring of other to be compared * begins at index <tt>ooffset</tt> and has length <tt>len</tt>. The * result is <tt>false</tt> if and only if at least one of the following * is true: * <ul><li><tt>toffset</tt> is negative. * <li><tt>ooffset</tt> is negative. * <li><tt>toffset+len</tt> is greater than the length of this * <tt>String</tt> object. * <li><tt>ooffset+len</tt> is greater than the length of the other * argument. * <li>There is some nonnegative integer <i>k</i> less than <tt>len</tt> * such that: * <tt>this.charAt(toffset+<i>k</i>) != other.charAt(ooffset+<i>k</i>)</tt> * </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</code> if the specified subregion of this string * exactly matches the specified subregion of the string argument; * <code>false</code> otherwise. */ public boolean regionMatches(int toffset, String other, int ooffset, int len) { char ta[] = value; int to = offset + toffset; char pa[] = other.value; int po = other.offset + 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 (ta[to++] != pa[po++]) { return false; } } return true; } /** * Tests if two string regions are equal. * <p> * A substring of this <tt>String</tt> object is compared to a substring * of the argument <tt>other</tt>. The result is <tt>true</tt> if these * substrings represent character sequences that are the same, ignoring * case if and only if <tt>ignoreCase</tt> is true. The substring of * this <tt>String</tt> object to be compared begins at index * <tt>toffset</tt> and has length <tt>len</tt>. The substring of * <tt>other</tt> to be compared begins at index <tt>ooffset</tt> and * has length <tt>len</tt>. The result is <tt>false</tt> if and only if * at least one of the following is true: * <ul><li><tt>toffset</tt> is negative. * <li><tt>ooffset</tt> is negative. * <li><tt>toffset+len</tt> is greater than the length of this * <tt>String</tt> object. * <li><tt>ooffset+len</tt> is greater than the length of the other * argument. * <li><tt>ignoreCase</tt> is <tt>false</tt> and there is some nonnegative * integer <i>k</i> less than <tt>len</tt> such that: * <blockquote><pre> * this.charAt(toffset+k) != other.charAt(ooffset+k) * </pre></blockquote> * <li><tt>ignoreCase</tt> is <tt>true</tt> and there is some nonnegative * integer <i>k</i> less than <tt>len</tt> 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</code>, 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</code> if the specified subregion of this string * matches the specified subregion of the string argument; * <code>false</code> otherwise. Whether the matching is exact * or case insensitive depends on the <code>ignoreCase</code> * argument. */ public boolean regionMatches(boolean ignoreCase, int toffset, String other, int ooffset, int len) { char ta[] = value; int to = offset + toffset; char pa[] = other.value; int po = other.offset + 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 = ta[to++]; char c2 = pa[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</code> if the character sequence represented by the * argument is a prefix of the substring of this object starting * at index <code>toffset</code>; <code>false</code> otherwise. * The result is <code>false</code> if <code>toffset</code> is * negative or greater than the length of this * <code>String</code> 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) { char ta[] = value; int to = offset + toffset; char pa[] = prefix.value; int po = prefix.offset; int pc = prefix.count; // Note: toffset might be near -1>>>1. if ((toffset < 0) || (toffset > count - pc)) { return false; } while (--pc >= 0) { if (ta[to++] != pa[po++]) { return false; } } return true; } /** * Tests if this string starts with the specified prefix. * * @param prefix the prefix. * @return <code>true</code> if the character sequence represented by the * argument is a prefix of the character sequence represented by * this string; <code>false</code> otherwise. * Note also that <code>true</code> will be returned if the * argument is an empty string or is equal to this * <code>String</code> 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</code> if the character sequence represented by the * argument is a suffix of the character sequence represented by * this object; <code>false</code> otherwise. Note that the * result will be <code>true</code> if the argument is the * empty string or is equal to this <code>String</code> 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</code> object is computed as * <blockquote><pre> * s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1] * </pre></blockquote> * using <code>int</code> arithmetic, where <code>s[i]</code> is the * <i>i</i>th character of the string, <code>n</code> is the length of * the string, and <code>^</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) { int off = offset; char val[] = value; int len = count; for (int i = 0; i < len; i++) { h = 31*h + val[off++]; } 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</code> occurs in the character sequence represented by * this <code>String</code> object, then the index (in Unicode * code units) of the first such occurrence is returned. For * values of <code>ch</code> 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</code>, 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</code> 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</code> 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</code> occurs in the * character sequence represented by this <code>String</code> * object at an index no smaller than <code>fromIndex</code>, then * the index of the first such occurrence is returned. For values * of <code>ch</code> 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) && (<i>k</i> >= fromIndex) * </pre></blockquote> * is true. For other values of <code>ch</code>, it is the * smallest value <i>k</i> such that: * <blockquote><pre> * (this.codePointAt(<i>k</i>) == ch) && (<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</code>, then * <code>-1</code> is returned. * * <p> * There is no restriction on the value of <code>fromIndex</code>. 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</code> is returned. * * <p>All indices are specified in <code>char</code> 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</code>, or <code>-1</code> * if the character does not occur. */ public int indexOf(int ch, int fromIndex) { int max = offset + count; char v[] = value; if (fromIndex < 0) { fromIndex = 0; } else if (fromIndex >= count) { // Note: fromIndex might be near -1>>>1. return -1; } int i = offset + 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)) for (; i < max ; i++) { if (v[i] == ch) { return i - offset; } } return -1; } if (ch <= Character.MAX_CODE_POINT) { // handle supplementary characters here char[] surrogates = Character.toChars(ch); for (; i < max; i++) { if (v[i] == surrogates[0]) { if (i + 1 == max) { break; } if (v[i+1] == surrogates[1]) { return i - offset; } } } } return -1; } /** * Returns the index within this string of the last occurrence of * the specified character. For values of <code>ch</code> 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</code>, 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</code> is returned. The * <code>String</code> 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</code> 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</code> 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) && (<i>k</i> <= fromIndex) * </pre></blockquote> * is true. For other values of <code>ch</code>, it is the * largest value <i>k</i> such that: * <blockquote><pre> * (this.codePointAt(<i>k</i>) == ch) && (<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</code>, then * <code>-1</code> is returned. * * <p>All indices are specified in <code>char</code> 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</code>. 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</code>, or <code>-1</code> * if the character does not occur before that point. */ public int lastIndexOf(int ch, int fromIndex) { int min = offset; char v[] = value; int i = offset + ((fromIndex >= count) ? count - 1 : 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)) for (; i >= min ; i--) { if (v[i] == ch) { return i - offset; } } return -1; } int max = offset + count; if (ch <= Character.MAX_CODE_POINT) { // handle supplementary characters here char[] surrogates = Character.toChars(ch); for (; i >= min; i--) { if (v[i] == surrogates[0]) { if (i + 1 == max) { break; } if (v[i+1] == surrogates[1]) { return i - offset; } } } } return -1; } /** * Returns the index within this string of the first occurrence of the * specified substring. The integer returned is the smallest value * <i>k</i> such that: * <blockquote><pre> * this.startsWith(str, <i>k</i>) * </pre></blockquote> * is <code>true</code>. * * @param str any string. * @return if the string argument occurs as a substring within this * object, then the index of the first character of the first * such substring is returned; if it does not occur as a * substring, <code>-1</code> is returned. */ 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. The integer * returned is the smallest value <tt>k</tt> for which: * <blockquote><pre> * k >= Math.min(fromIndex, this.length()) && this.startsWith(str, k) * </pre></blockquote> * If no such value of <i>k</i> exists, then -1 is returned. * * @param str the substring for which to search. * @param fromIndex the index from which to start the search. * @return the index within this string of the first occurrence of the * specified substring, starting at the specified index. */ public int indexOf(String str, int fromIndex) { return indexOf(value, offset, count, str.value, str.offset, str.count, fromIndex); } /** * 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 rightmost occurrence * of the specified substring. The rightmost empty string "" is * considered to occur at the index value <code>this.length()</code>. * The returned index is the largest value <i>k</i> such that * <blockquote><pre> * this.startsWith(str, k) * </pre></blockquote> * is true. * * @param str the substring to search for. * @return if the string argument occurs one or more times as a substring * within this object, then the index of the first character of * the last such substring is returned. If it does not occur as * a substring, <code>-1</code> is returned. */ 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. * The integer returned is the largest value <i>k</i> such that: * <blockquote><pre> * k <= Math.min(fromIndex, this.length()) && this.startsWith(str, k) * </pre></blockquote> * If no such value of <i>k</i> exists, then -1 is returned. * * @param str the substring to search for. * @param fromIndex the index to start the search from. * @return the index within this string of the last occurrence of the * specified substring. */ public int lastIndexOf(String str, int fromIndex) { return lastIndexOf(value, offset, count, str.value, str.offset, str.count, fromIndex); } /** * 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 new 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</code> is negative or larger than the * length of this <code>String</code> object. */ public String substring(int beginIndex) { return substring(beginIndex, count); } /** * Returns a new string that is a substring of this string. The * substring begins at the specified <code>beginIndex</code> and * extends to the character at index <code>endIndex - 1</code>. * Thus the length of the substring is <code>endIndex-beginIndex</code>. * <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</code> is negative, or * <code>endIndex</code> is larger than the length of * this <code>String</code> object, or * <code>beginIndex</code> is larger than * <code>endIndex</code>. */ public String substring(int beginIndex, int endIndex) { if (beginIndex < 0) { throw new StringIndexOutOfBoundsException(beginIndex); } if (endIndex > count) { throw new StringIndexOutOfBoundsException(endIndex); } if (beginIndex > endIndex) { throw new StringIndexOutOfBoundsException(endIndex - beginIndex); } return ((beginIndex == 0) && (endIndex == count)) ? this : new String(offset + beginIndex, endIndex - beginIndex, value); } /** * Returns a new 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> * * This method is defined so that the <tt>String</tt> class can implement * the {@link CharSequence} interface. </p> * * @param beginIndex the begin index, inclusive. * @param endIndex the end index, exclusive. * @return the specified subsequence. * * @throws IndexOutOfBoundsException * if <tt>beginIndex</tt> or <tt>endIndex</tt> are negative, * if <tt>endIndex</tt> is greater than <tt>length()</tt>, * or if <tt>beginIndex</tt> is greater than <tt>startIndex</tt> * * @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</code>, then this * <code>String</code> object is returned. Otherwise, a new * <code>String</code> object is created, representing a character * sequence that is the concatenation of the character sequence * represented by this <code>String</code> 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</code> that is concatenated to the end * of this <code>String</code>. * @return a string that represents the concatenation of this object's * characters followed by the string argument's characters. */ public String concat(String str) { int otherLen = str.length(); if (otherLen == 0) { return this; } char buf[] = new char[count + otherLen]; getChars(0, count, buf, 0); str.getChars(0, otherLen, buf, count); return new String(0, count + otherLen, buf); } /** * Returns a new string resulting from replacing all occurrences of * <code>oldChar</code> in this string with <code>newChar</code>. * <p> * If the character <code>oldChar</code> does not occur in the * character sequence represented by this <code>String</code> object, * then a reference to this <code>String</code> object is returned. * Otherwise, a new <code>String</code> object is created that * represents a character sequence identical to the character sequence * represented by this <code>String</code> object, except that every * occurrence of <code>oldChar</code> is replaced by an occurrence * of <code>newChar</code>. * <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</code> with <code>newChar</code>. */ public String replace(char oldChar, char newChar) { if (oldChar != newChar) { int len = count; int i = -1; char[] val = value; /* avoid getfield opcode */ int off = offset; /* avoid getfield opcode */ while (++i < len) { if (val[off + i] == oldChar) { break; } } if (i < len) { char buf[] = new char[len]; for (int j = 0 ; j < i ; j++) { buf[j] = val[off+j]; } while (i < len) { char c = val[off + i]; buf[i] = (c == oldChar) ? newChar : c; i++; } return new String(0, len, buf); } } return this; } /** * 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><tt>.matches(</tt><i>regex</i><tt>)</tt> yields exactly the * same result as the expression * * <blockquote><tt> {@link java.util.regex.Pattern}.{@link * java.util.regex.Pattern#matches(String,CharSequence) * matches}(</tt><i>regex</i><tt>,</tt> <i>str</i><tt>)</tt></blockquote> * * @param regex * the regular expression to which this string is to be matched * * @return <tt>true</tt> 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</code>, false otherwise * @throws NullPointerException if <code>s</code> is <code>null</code> * @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><tt>.replaceFirst(</tt><i>regex</i><tt>,</tt> <i>repl</i><tt>)</tt> * yields exactly the same result as the expression * * <blockquote><tt> * {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#compile * compile}(</tt><i>regex</i><tt>).{@link * java.util.regex.Pattern#matcher(java.lang.CharSequence) * matcher}(</tt><i>str</i><tt>).{@link java.util.regex.Matcher#replaceFirst * replaceFirst}(</tt><i>repl</i><tt>)</tt></blockquote> * *<p> * Note that backslashes (<tt>/</tt>) and dollar signs (<tt>$</tt>) in the * replacement string may cause the results to be different than if it were * being treated as a literal replacement string; see * {@link java.util.regex.Matcher#replaceFirst}. * Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special * meaning of these characters, if desired. * * @param regex * the regular expression to which this string is to be matched * @param replacement * the string to be substituted for the first match * * @return The resulting <tt>String</tt> * * @throws PatternSyntaxException * if the regular expression's syntax is invalid * * @see java.util.regex.Pattern * * @since 1.4 * @spec JSR-51 */ public String replaceFirst(String regex, String replacement) { return Pattern.compile(regex).matcher(this).replaceFirst(replacement); } /** * Replaces each substring of this string that matches the given <a * href="../util/regex/Pattern.html#sum">regular expression</a> with the * given replacement. * * <p> An invocation of this method of the form * <i>str</i><tt>.replaceAll(</tt><i>regex</i><tt>,</tt> <i>repl</i><tt>)</tt> * yields exactly the same result as the expression * * <blockquote><tt> * {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#compile * compile}(</tt><i>regex</i><tt>).{@link * java.util.regex.Pattern#matcher(java.lang.CharSequence) * matcher}(</tt><i>str</i><tt>).{@link java.util.regex.Matcher#replaceAll * replaceAll}(</tt><i>repl</i><tt>)</tt></blockquote> * *<p> * Note that backslashes (<tt>/</tt>) and dollar signs (<tt>$</tt>) 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 <tt>String</tt> * * @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) { return Pattern.compile(target.toString(), Pattern.LITERAL).matcher( this).replaceAll(Matcher.quoteReplacement(replacement.toString())); } /** * Splits this string around matches of the given * <a href="../util/regex/Pattern.html#sum" mce_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> The <tt>limit</tt> 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 <tt>"boo:and:foo"</tt>, 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><tt>{ "boo", "and:foo" }</tt></td></tr> * <tr><td align=center>:</td> * <td align=center>5</td> * <td><tt>{ "boo", "and", "foo" }</tt></td></tr> * <tr><td align=center>:</td> * <td align=center>-2</td> * <td><tt>{ "boo", "and", "foo" }</tt></td></tr> * <tr><td align=center>o</td> * <td align=center>5</td> * <td><tt>{ "b", "", ":and:f", "", "" }</tt></td></tr> * <tr><td align=center>o</td> * <td align=center>-2</td> * <td><tt>{ "b", "", ":and:f", "", "" }</tt></td></tr> * <tr><td align=center>o</td> * <td align=center>0</td> * <td><tt>{ "b", "", ":and:f" }</tt></td></tr> * </table></blockquote> * * <p> An invocation of this method of the form * <i>str.</i><tt>split(</tt><i>regex</i><tt>,</tt> <i>n</i><tt>)</tt> * yields the same result as the expression * * <blockquote> * {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#compile * compile}<tt>(</tt><i>regex</i><tt>)</tt>.{@link * java.util.regex.Pattern#split(java.lang.CharSequence,int) * split}<tt>(</tt><i>str</i><tt>,</tt> <i>n</i><tt>)</tt> * </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) { 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 <tt>"boo:and:foo"</tt>, 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><tt>{ "boo", "and", "foo" }</tt></td></tr> * <tr><td align=center>o</td> * <td><tt>{ "b", "", ":and:f" }</tt></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); } /** * Converts all of the characters in this <code>String</code> to lower * case using the rules of the given <code>Locale</code>. 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</code> may be a different length than the original <code>String</code>. * <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" mce_src="doc-files/capiota.gif" alt="capiota"><img src="doc-files/capchi.gif" mce_src="doc-files/capchi.gif" alt="capchi"> * <img src="doc-files/captheta.gif" mce_src="doc-files/captheta.gif" alt="captheta"><img src="doc-files/capupsil.gif" mce_src="doc-files/capupsil.gif" alt="capupsil"> * <img src="doc-files/capsigma.gif" mce_src="doc-files/capsigma.gif" alt="capsigma"></td> * <td><img src="doc-files/iota.gif" mce_src="doc-files/iota.gif" alt="iota"><img src="doc-files/chi.gif" mce_src="doc-files/chi.gif" alt="chi"> * <img src="doc-files/theta.gif" mce_src="doc-files/theta.gif" alt="theta"><img src="doc-files/upsilon.gif" mce_src="doc-files/upsilon.gif" alt="upsilon"> * <img src="doc-files/sigma1.gif" mce_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</code>, 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) { if (locale == null) { throw new NullPointerException(); } int firstUpper; /* Now check if there are any characters that need to be changed. */ scan: { for (firstUpper = 0 ; firstUpper < count; ) { char c = value[offset+firstUpper]; if ((c >= Character.MIN_HIGH_SURROGATE) && (c <= Character.MAX_HIGH_SURROGATE)) { int supplChar = codePointAt(firstUpper); if (supplChar != Character.toLowerCase(supplChar)) { break scan; } firstUpper += Character.charCount(supplChar); } else { if (c != Character.toLowerCase(c)) { break scan; } firstUpper++; } } return this; } char[] result = new char[count]; int resultOffset = 0; /* result may grow, so i+resultOffset * is the write location in result */ /* Just copy the first few lowerCase characters. */ System.arraycopy(value, offset, result, 0, firstUpper); String lang = locale.getLanguage(); boolean localeDependent = (lang == "tr" || lang == "az" || lang == "lt"); char[] lowerCharArray; int lowerChar; int srcChar; int srcCount; for (int i = firstUpper; i < count; i += srcCount) { srcChar = (int)value[offset+i]; if ((char)srcChar >= Character.MIN_HIGH_SURROGATE && (char)srcChar <= Character.MAX_HIGH_SURROGATE) { srcChar = codePointAt(i); srcCount = Character.charCount(srcChar); } else { srcCount = 1; } if (localeDependent || srcChar == '/u03A3') { // GREEK CAPITAL LETTER SIGMA lowerChar = ConditionalSpecialCasing.toLowerCaseEx(this, i, locale); } else { lowerChar = Character.toLowerCase(srcChar); } if ((lowerChar == Character.ERROR) || (lowerChar >= Character.MIN_SUPPLEMENTARY_CODE_POINT)) { if (lowerChar == Character.ERROR) { lowerCharArray = ConditionalSpecialCasing.toLowerCaseCharArray(this, i, locale); } else if (srcCount == 2) { resultOffset += Character.toChars(lowerChar, result, i + resultOffset) - srcCount; continue; } else { lowerCharArray = Character.toChars(lowerChar); } /* Grow result if needed */ int mapLen = lowerCharArray.length; if (mapLen > srcCount) { char[] result2 = new char[result.length + mapLen - srcCount]; System.arraycopy(result, 0, result2, 0, i + resultOffset); result = result2; } for (int x=0; x<mapLen; ++x) { result[i+resultOffset+x] = lowerCharArray[x]; } resultOffset += (mapLen - srcCount); } else { result[i+resultOffset] = (char)lowerChar; } } return new String(0, count+resultOffset, result); } /** * Converts all of the characters in this <code>String</code> to lower * case using the rules of the default locale. This is equivalent to calling * <code>toLowerCase(Locale.getDefault())</code>. * <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()</code> in a Turkish locale * returns <code>"t/u0131tle"</code>, where '/u0131' is the LATIN SMALL * LETTER DOTLESS I character. * To obtain correct results for locale insensitive strings, use * <code>toLowerCase(Locale.ENGLISH)</code>. * <p> * @return the <code>String</code>, 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</code> to upper * case using the rules of the given <code>Locale</code>. 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</code> may be a different length than the original <code>String</code>. * <p> * Examples of locale-sensitive and 1:M case mappings are in the following table. * <p> * <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</code>, 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) { if (locale == null) { throw new NullPointerException(); } int firstLower; /* Now check if there are any characters that need to be changed. */ scan: { for (firstLower = 0 ; firstLower < count; ) { int c = (int)value[offset+firstLower]; int srcCount; if ((c >= Character.MIN_HIGH_SURROGATE) && (c <= Character.MAX_HIGH_SURROGATE)) { c = codePointAt(firstLower); srcCount = Character.charCount(c); } else { srcCount = 1; } int upperCaseChar = Character.toUpperCaseEx(c); if ((upperCaseChar == Character.ERROR) || (c != upperCaseChar)) { break scan; } firstLower += srcCount; } return this; } char[] result = new char[count]; /* may grow */ int resultOffset = 0; /* result may grow, so i+resultOffset * is the write location in result */ /* Just copy the first few upperCase characters. */ System.arraycopy(value, offset, result, 0, firstLower); String lang = locale.getLanguage(); boolean localeDependent = (lang == "tr" || lang == "az" || lang == "lt"); char[] upperCharArray; int upperChar; int srcChar; int srcCount; for (int i = firstLower; i < count; i += srcCount) { srcChar = (int)value[offset+i]; if ((char)srcChar >= Character.MIN_HIGH_SURROGATE && (char)srcChar <= Character.MAX_HIGH_SURROGATE) { srcChar = codePointAt(i); srcCount = Character.charCount(srcChar); } else { srcCount = 1; } if (localeDependent) { upperChar = ConditionalSpecialCasing.toUpperCaseEx(this, i, locale); } else { upperChar = Character.toUpperCaseEx(srcChar); } if ((upperChar == Character.ERROR) || (upperChar >= Character.MIN_SUPPLEMENTARY_CODE_POINT)) { if (upperChar == Character.ERROR) { if (localeDependent) { upperCharArray = ConditionalSpecialCasing.toUpperCaseCharArray(this, i, locale); } else { upperCharArray = Character.toUpperCaseCharArray(srcChar); } } else if (srcCount == 2) { resultOffset += Character.toChars(upperChar, result, i + resultOffset) - srcCount; continue; } else { upperCharArray = Character.toChars(upperChar); } /* Grow result if needed */ int mapLen = upperCharArray.length; if (mapLen > srcCount) { char[] result2 = new char[result.length + mapLen - srcCount]; System.arraycopy(result, 0, result2, 0, i + resultOffset); result = result2; } for (int x=0; x<mapLen; ++x) { result[i+resultOffset+x] = upperCharArray[x]; } resultOffset += (mapLen - srcCount); } else { result[i+resultOffset] = (char)upperChar; } } return new String(0, count+resultOffset, result); } /** * Converts all of the characters in this <code>String</code> to upper * case using the rules of the default locale. This method is equivalent to * <code>toUpperCase(Locale.getDefault())</code>. * <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()</code> in a Turkish locale * returns <code>"T/u0130TLE"</code>, where '/u0130' is the LATIN CAPITAL * LETTER I WITH DOT ABOVE character. * To obtain correct results for locale insensitive strings, use * <code>toUpperCase(Locale.ENGLISH)</code>. * <p> * @return the <code>String</code>, converted to uppercase. * @see java.lang.String#toUpperCase(Locale) */ public String toUpperCase() { return toUpperCase(Locale.getDefault()); } /** * Returns a copy of the string, with leading and trailing whitespace * omitted. * <p> * If this <code>String</code> object represents an empty character * sequence, or the first and last characters of character sequence * represented by this <code>String</code> object both have codes * greater than <code>'/u0020'</code> (the space character), then a * reference to this <code>String</code> object is returned. * <p> * Otherwise, if there is no character with a code greater than * <code>'/u0020'</code> in the string, then a new * <code>String</code> object representing an empty string is created * and returned. * <p> * Otherwise, let <i>k</i> be the index of the first character in the * string whose code is greater than <code>'/u0020'</code>, and let * <i>m</i> be the index of the last character in the string whose code * is greater than <code>'/u0020'</code>. A new <code>String</code> * object is created, 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(<i>k</i>, <i>m</i>+1)</code>. * <p> * This method may be used to trim whitespace (as defined above) from * the beginning and end of a string. * * @return A copy of this string with 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; int off = offset; /* avoid getfield opcode */ char[] val = value; /* avoid getfield opcode */ while ((st < len) && (val[off + st] <= ' ')) { st++; } while ((st < len) && (val[off + 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 char[] toCharArray() { char result[] = new char[count]; getChars(0, count, result, 0); return result; } /** * 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" mce_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 * the <a href="http://java.sun.com/docs/books/vmspec/" mce_href="http://java.sun.com/docs/books/vmspec/">Java * Virtual Machine Specification</a>. The behaviour on a * <tt>null</tt> argument depends on the <a * href="../util/Formatter.html#syntax">conversion</a>. * * @throws 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 <tt>l</tt> is <tt>null</tt> then no localization * is applied. * * @param format * A <a href="../util/Formatter.html#syntax" mce_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 * the <a href="http://java.sun.com/docs/books/vmspec/" mce_href="http://java.sun.com/docs/books/vmspec/">Java * Virtual Machine Specification</a>. The behaviour on a * <tt>null</tt> argument depends on the <a * href="../util/Formatter.html#syntax">conversion</a>. * * @throws 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</code> argument. * * @param obj an <code>Object</code>. * @return if the argument is <code>null</code>, then a string equal to * <code>"null"</code>; otherwise, the value of * <code>obj.toString()</code> 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</code> array * argument. The contents of the character array are copied; subsequent * modification of the character array does not affect the newly * created string. * * @param data a <code>char</code> array. * @return a newly allocated string representing the same sequence of * characters contained in the character array argument. */ public static String valueOf(char data[]) { return new String(data); } /** * Returns the string representation of a specific subarray of the * <code>char</code> array argument. * <p> * The <code>offset</code> argument is the index of the first * character of the subarray. The <code>count</code> 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 data the character array. * @param offset the initial offset into the value of the * <code>String</code>. * @param count the length of the value of the <code>String</code>. * @return a string representing the sequence of characters contained * in the subarray of the character array argument. * @exception IndexOutOfBoundsException if <code>offset</code> is * negative, or <code>count</code> is negative, or * <code>offset+count</code> is larger than * <code>data.length</code>. */ public static String valueOf(char data[], int offset, int count) { return new String(data, offset, count); } /** * Returns a String that represents the character sequence in the * array specified. * * @param data the character array. * @param offset initial offset of the subarray. * @param count length of the subarray. * @return a <code>String</code> that contains the characters of the * specified subarray of the character array. */ public static String copyValueOf(char data[], int offset, int count) { // All public String constructors now copy the data. return new String(data, offset, count); } /** * Returns a String that represents the character sequence in the * array specified. * * @param data the character array. * @return a <code>String</code> that contains the characters of the * character array. */ public static String copyValueOf(char data[]) { return copyValueOf(data, 0, data.length); } /** * Returns the string representation of the <code>boolean</code> argument. * * @param b a <code>boolean</code>. * @return if the argument is <code>true</code>, a string equal to * <code>"true"</code> is returned; otherwise, a string equal to * <code>"false"</code> is returned. */ public static String valueOf(boolean b) { return b ? "true" : "false"; } /** * Returns the string representation of the <code>char</code> * argument. * * @param c a <code>char</code>. * @return a string of length <code>1</code> containing * as its single character the argument <code>c</code>. */ public static String valueOf(char c) { char data[] = {c}; return new String(0, 1, data); } /** * Returns the string representation of the <code>int</code> argument. * <p> * The representation is exactly the one returned by the * <code>Integer.toString</code> method of one argument. * * @param i an <code>int</code>. * @return a string representation of the <code>int</code> argument. * @see java.lang.Integer#toString(int, int) */ public static String valueOf(int i) { return Integer.toString(i, 10); } /** * Returns the string representation of the <code>long</code> argument. * <p> * The representation is exactly the one returned by the * <code>Long.toString</code> method of one argument. * * @param l a <code>long</code>. * @return a string representation of the <code>long</code> argument. * @see java.lang.Long#toString(long) */ public static String valueOf(long l) { return Long.toString(l, 10); } /** * Returns the string representation of the <code>float</code> argument. * <p> * The representation is exactly the one returned by the * <code>Float.toString</code> method of one argument. * * @param f a <code>float</code>. * @return a string representation of the <code>float</code> 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</code> argument. * <p> * The representation is exactly the one returned by the * <code>Double.toString</code> method of one argument. * * @param d a <code>double</code>. * @return a string representation of the <code>double</code> 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</code>. * <p> * When the intern method is invoked, if the pool already contains a * string equal to this <code>String</code> object as determined by * the {@link #equals(Object)} method, then the string from the pool is * returned. Otherwise, this <code>String</code> object is added to the * pool and a reference to this <code>String</code> object is returned. * <p> * It follows that for any two strings <code>s</code> and <code>t</code>, * <code>s.intern() == t.intern()</code> is <code>true</code> * if and only if <code>s.equals(t)</code> is <code>true</code>. * <p> * All literal strings and string-valued constant expressions are * interned. String literals are defined in §3.10.5 of the * <a href="http://java.sun.com/docs/books/jls/html/" mce_href="http://java.sun.com/docs/books/jls/html/">Java Language * Specification</a> * * @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(); }  

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