java string

[size=medium][color=green]/*
* @(#)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 (&nbsp;+&nbsp;), 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">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&nbsp;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 &amp; 0xff) &lt;&lt;
     *                         | (<b><i>b</i></b> &amp; 0xff))
     * </pre></blockquote>
     *
     * @deprecated  This method does not properly convert bytes into
     * characters.  As of JDK&nbsp;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">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">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&nbsp;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 &lt; 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>)&nbsp;!=&nbsp;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> &gt;= 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> &gt;= 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> &lt;= 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> &lt;= 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
     *