/*
 * @(#)StringBuffer.java	1.33 97/01/24
 * 
 * Copyright (c) 1995, 1996 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the confidential and proprietary information of Sun
 * Microsystems, Inc. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with Sun.
 * 
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
 * SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
 * THIS SOFTWARE OR ITS DERIVATIVES.
 * 
 * CopyrightVersion 1.1_beta
 * 
 */

package java.lang;

/**
 * A string buffer implements a mutable sequence of characters. 
 * <p>
 * String buffers are safe for use by multiple threads. The methods 
 * are synchronized where necessary so that all the operations on any 
 * particular instance behave as if they occur in some serial order. 
 * <p>
 * String buffers are used by the compiler to implement the binary 
 * string concatenation operator <code>+</code>. For example, the code:
 * <p><blockquote><pre>
 *     x = "a" + 4 + "c"
 * </pre></blockquote><p>
 * is compiled to the equivalent of: 
 * <p><blockquote><pre>
 *     x = new StringBuffer().append("a").append(4).append("c")
 *                           .toString()
 * </pre></blockquote><p>
 * The principal operations on a <code>StringBuffer</code> are the 
 * <code>append</code> and <code>insert</code> methods, which are 
 * overloaded so as to accept data of any type. Each effectively 
 * converts a given datum to a string and then appends or inserts the 
 * characters of that string to the string buffer. The 
 * <code>append</code> method always adds these characters at the end 
 * of the buffer; the <code>insert</code> method adds the characters at 
 * a specified point. 
 * <p>
 * For example, if <code>z</code> refers to a string buffer object 
 * whose current contents are "<code>start</code>", then 
 * the method call <code>z.append("le")</code> would cause the string 
 * buffer to contain "<code>startle</code>", whereas 
 * <code>z.insert(4, "le")</code> would alter the string buffer to 
 * contain "<code>starlet</code>". 
 * <p>
 * Every string buffer has a capacity. As long as the length of the 
 * character sequence contained in the string buffer does not exceed 
 * the capacity, it is not necessary to allocate a new internal 
 * buffer array. If the internal buffer overflows, it is 
 * automatically made larger. 
 *
 * @author	Arthur van Hoff
 * @version 	1.33, 24 Jan 1997
 * @see     java.io.ByteArrayOutputStream
 * @see     java.lang.String
 * @since   JDK1.0
 */
 
public final class StringBuffer implements java.io.Serializable {
    /** The value is used for character storage. */
    private char value[];

    /** The count is the number of characters in the buffer. */
    private int count;

    /** A flag indicating whether the buffer is shared */
    private boolean shared;

    /** use serialVersionUID from JDK 1.0.2 for interoperability */
    static final long serialVersionUID = 3388685877147921107L;

    /**
     * Constructs a string buffer with no characters in it and an 
     * initial capacity of 16 characters. 
     *
     * @since   JDK1.0
     */
    public StringBuffer() {
	this(16);
    }

    /**
     * Constructs a string buffer with no characters in it and an 
     * initial capacity specified by the <code>length</code> argument. 
     *
     * @param      length   the initial capacity.
     * @exception  NegativeArraySizeException  if the <code>length</code>
     *               argument is less than <code>0</code>.
     * @since      JDK1.0
     */
    public StringBuffer(int length) {
	value = new char[length];
	shared = false;
    }

    /**
     * Constructs a string buffer so that it represents the same 
     * sequence of characters as the string argument. The initial 
     * capacity of the string buffer is <code>16</code> plus the length 
     * of the string argument. 
     *
     * @param   str   the initial contents of the buffer.
     * @since   JDK1.0
     */
    public StringBuffer(String str) {
	this(str.length() + 16);
	append(str);
    }

    /**
     * Returns the length (character count) of this string buffer.
     *
     * @return  the number of characters in this string buffer.
     * @since   JDK1.0
     */
    public int length() {
	return count;
    }

    /**
     * Returns the current capacity of the String buffer. The capacity
     * is the amount of storage available for newly inserted
     * characters; beyond which an allocation will occur.
     *
     * @return  the current capacity of this string buffer.
     * @since   JDK1.0
     */
    public int capacity() {
	return value.length;
    }

    /**
     * Copies the buffer value if it is shared.
     */
    private final void copyWhenShared() {
	if (shared) {
	    char newValue[] = new char[value.length];
	    System.arraycopy(value, 0, newValue, 0, count);
	    value = newValue;
	    shared = false;
	}
    }

    /**
     * Ensures that the capacity of the buffer is at least equal to the
     * specified minimum.
     * If the current capacity of this string buffer is less than the 
     * argument, then a new internal buffer is allocated with greater 
     * capacity. The new capacity is the larger of: 
     * <ul>
     * <li>The <code>minimumCapacity</code> argument. 
     * <li>Twice the old capacity, plus <code>2</code>. 
     * </ul>
     * If the <code>minimumCapacity</code> argument is nonpositive, this
     * method takes no action and simply returns.
     *
     * @param   minimumCapacity   the minimum desired capacity.
     * @since   JDK1.0
     */
    public synchronized void ensureCapacity(int minimumCapacity) {
	int maxCapacity = value.length;

	if (minimumCapacity > maxCapacity) {
	    int newCapacity = (maxCapacity + 1) * 2;
	    if (minimumCapacity > newCapacity) {
		newCapacity = minimumCapacity;
	    }

	    char newValue[] = new char[newCapacity];
	    System.arraycopy(value, 0, newValue, 0, count);
	    value = newValue;
	    shared = false;
	}
    }

    /**
     * Sets the length of this String buffer.
     * If the <code>newLength</code> argument is less than the current 
     * length of the string buffer, the string buffer is truncated to 
     * contain exactly the number of characters given by the 
     * <code>newLength</code> argument. 
     * <p>
     * If the <code>newLength</code> argument is greater than or equal 
     * to the current length, sufficient null characters 
     * (<code>'&#92;u0000'</code>) are appended to the string buffer so that 
     * length becomes the <code>newLength</code> argument. 
     * <p>
     * The <code>newLength</code> argument must be greater than or equal 
     * to <code>0</code>. 
     *
     * @param      newLength   the new length of the buffer.
     * @exception  StringIndexOutOfBoundsException  if the
     *               <code>newLength</code> argument is invalid.
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized void setLength(int newLength) {
	if (newLength < 0) {
	    throw new StringIndexOutOfBoundsException(newLength);
	}
	ensureCapacity(newLength);

	if (count < newLength) {
	    copyWhenShared();
	    for (; count < newLength; count++) {
		value[count] = '\0';
	    }
	}
	count = newLength;
    }

    /**
     * Returns the character at a specific index in this string buffer. 
     * <p>
     * The first character of a string buffer is at index 
     * <code>0</code>, the next at index <code>1</code>, and so on, for 
     * array indexing. 
     * <p>
     * The index argument must be greater than or equal to 
     * <code>0</code>, and less than the length of this string buffer. 
     *
     * @param      index   the index of the desired character.
     * @return     the character at the specified index of this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the index is invalid.
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized char charAt(int index) {
	if ((index < 0) || (index >= count)) {
	    throw new StringIndexOutOfBoundsException(index);
	}
	return value[index];
    }

    /**
     * Characters are copied from this string buffer into the 
     * destination character array <code>dst</code>. 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> 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   start copying at this offset in the string buffer.
     * @param      srcEnd     stop copying at this offset in the string buffer.
     * @param      dst        the array to copy the data into.
     * @param      dstBegin   offset into <code>dst</code>.
     * @exception  StringIndexOutOfBoundsException  if there is an invalid
     *               index into the buffer.
     * @since      JDK1.0
     */
    public synchronized void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) {
	if ((srcBegin < 0) || (srcBegin >= count)) {
	    throw new StringIndexOutOfBoundsException(srcBegin);
	}
	if ((srcEnd < 0) || (srcEnd > count)) {
	    throw new StringIndexOutOfBoundsException(srcEnd);
	}
	if (srcBegin < srcEnd) {
	    System.arraycopy(value, srcBegin, dst, dstBegin, srcEnd - srcBegin);
	}
    }

    /**
     * The character at the specified index of this string buffer is set 
     * to <code>ch</code>. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than the length of this string buffer. 
     *
     * @param      index   the index of the character to modify.
     * @param      ch      the new character.
     * @exception  StringIndexOutOfBoundsException  if the index is invalid.
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized void setCharAt(int index, char ch) {
	if ((index < 0) || (index >= count)) {
	    throw new StringIndexOutOfBoundsException(index);
	}
	copyWhenShared();
	value[index] = ch;
    }

    /**
     * Appends the string representation of the <code>Object</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   obj   an <code>Object</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(java.lang.Object)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public synchronized StringBuffer append(Object obj) {
	return append(String.valueOf(obj));
    }

    /**
     * Appends the string to this string buffer. 
     * <p>
     * The characters of the <code>String</code> argument are appended, in 
     * order, to the contents of this string buffer, increasing the 
     * length of this string buffer by the length of the argument. 
     *
     * @param   str   a string.
     * @return  this string buffer.
     * @since   JDK1.0
     */
    public synchronized StringBuffer append(String str) {
	if (str == null) {
	    str = String.valueOf(str);
	}

	int len = str.length();
	ensureCapacity(count + len);
	copyWhenShared();
	str.getChars(0, len, value, count);
	count += len;
	return this;
    }

    /**
     * Appends the string representation of the <code>char</code> array 
     * argument to this string buffer. 
     * <p>
     * The characters of the array argument are appended, in order, to 
     * the contents of this string buffer. The length of this string 
     * buffer increases by the length of the argument. 
     *
     * @param   str   the characters to be appended.
     * @return  this string buffer.
     * @since   JDK1.0
     */
    public synchronized StringBuffer append(char str[]) {
	int len = str.length;
	ensureCapacity(count + len);
	copyWhenShared();
	System.arraycopy(str, 0, value, count, len);
	count += len;
	return this;
    }

    /**
     * Appends the string representation of a subarray of the 
     * <code>char</code> array argument to this string buffer. 
     * <p>
     * Characters of the character array <code>str</code>, starting at 
     * index <code>offset</code>, are appended, in order, to the contents 
     * of this string buffer. The length of this string buffer increases 
     * by the value of <code>len</code>. 
     *
     * @param   str      the characters to be appended.
     * @param   offset   the index of the first character to append.
     * @param   len      the number of characters to append.
     * @return  this string buffer.
     * @since   JDK1.0
     */
    public synchronized StringBuffer append(char str[], int offset, int len) {
	ensureCapacity(count + len);
	copyWhenShared();
	System.arraycopy(str, offset, value, count, len);
	count += len;
	return this;
    }

    /**
     * Appends the string representation of the <code>boolean</code> 
     * argument to the string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   b   a <code>boolean</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(boolean)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public StringBuffer append(boolean b) {
	return append(String.valueOf(b));
    }

    /**
     * Appends the string representation of the <code>char</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is appended to the contents of this string buffer. 
     * The length of this string buffer increases by <code>1</code>. 
     *
     * @param   ch   a <code>char</code>.
     * @return  this string buffer.
     * @since   JDK1.0
     */
    public synchronized StringBuffer append(char c) {
	ensureCapacity(count + 1);
	copyWhenShared();
	value[count++] = c;
	return this;
    }

    /**
     * Appends the string representation of the <code>int</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   i   an <code>int</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(int)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public StringBuffer append(int i) {
	return append(String.valueOf(i));
    }

    /**
     * Appends the string representation of the <code>long</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   l   a <code>long</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(long)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public StringBuffer append(long l) {
	return append(String.valueOf(l));
    }

    /**
     * Appends the string representation of the <code>float</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   f   a <code>float</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(float)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public StringBuffer append(float f) {
	return append(String.valueOf(f));
    }

    /**
     * Appends the string representation of the <code>double</code> 
     * argument to this string buffer. 
     * <p>
     * The argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then appended to this string buffer. 
     *
     * @param   d   a <code>double</code>.
     * @return  this string buffer.
     * @see     java.lang.String#valueOf(double)
     * @see     java.lang.StringBuffer#append(java.lang.String)
     * @since   JDK1.0
     */
    public StringBuffer append(double d) {
	return append(String.valueOf(d));
    }

    /**
     * Inserts the string representation of the <code>Object</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        an <code>Object</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(java.lang.Object)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized StringBuffer insert(int offset, Object obj) {
	return insert(offset, String.valueOf(obj));
    }

    /**
     * Inserts the string into this string buffer. 
     * <p>
     * The characters of the <code>String</code> argument are inserted, in 
     * order, into this string buffer at the indicated offset. The length 
     * of this string buffer is increased by the length of the argument. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      str      a string.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized StringBuffer insert(int offset, String str) {
	if ((offset < 0) || (offset > count)) {
	    throw new StringIndexOutOfBoundsException();
	}
	int len = str.length();
	ensureCapacity(count + len);
	copyWhenShared();
	System.arraycopy(value, offset, value, offset + len, count - offset);
	str.getChars(0, len, value, offset);
	count += len;
	return this;
    }

    /**
     * Inserts the string representation of the <code>char</code> array 
     * argument into this string buffer. 
     * <p>
     * The characters of the array argument are inserted into the 
     * contents of this string buffer at the position indicated by 
     * <code>offset</code>. The length of this string buffer increases by 
     * the length of the argument. 
     *
     * @param      offset   the offset.
     * @param      ch       a character array.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @since      JDK1.0
     */
    public synchronized StringBuffer insert(int offset, char str[]) {
	if ((offset < 0) || (offset > count)) {
	    throw new StringIndexOutOfBoundsException();
	}
	int len = str.length;
	ensureCapacity(count + len);
	copyWhenShared();
	System.arraycopy(value, offset, value, offset + len, count - offset);
	System.arraycopy(str, 0, value, offset, len);
	count += len;
	return this;
    }

    /**
     * Inserts the string representation of the <code>boolean</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        a <code>boolean</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(boolean)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public StringBuffer insert(int offset, boolean b) {
	return insert(offset, String.valueOf(b));
    }

    /**
     * Inserts the string representation of the <code>char</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is inserted into the contents of this string 
     * buffer at the position indicated by <code>offset</code>. The length 
     * of this string buffer increases by one. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      ch       a <code>char</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public synchronized StringBuffer insert(int offset, char c) {
	ensureCapacity(count + 1);
	copyWhenShared();
	System.arraycopy(value, offset, value, offset + 1, count - offset);
	value[offset] = c;
	count += 1;
	return this;
    }

    /**
     * Inserts the string representation of the second <code>int</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        an <code>int</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(int)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public StringBuffer insert(int offset, int i) {
	return insert(offset, String.valueOf(i));
    }

    /**
     * Inserts the string representation of the <code>long</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        a <code>long</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(long)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public StringBuffer insert(int offset, long l) {
	return insert(offset, String.valueOf(l));
    }

    /**
     * Inserts the string representation of the <code>float</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        a <code>float</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(float)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public StringBuffer insert(int offset, float f) {
	return insert(offset, String.valueOf(f));
    }

    /**
     * Inserts the string representation of the <code>double</code> 
     * argument into this string buffer. 
     * <p>
     * The second argument is converted to a string as if by the method 
     * <code>String.valueOf</code>, and the characters of that 
     * string are then inserted into this string buffer at the indicated 
     * offset. 
     * <p>
     * The offset argument must be greater than or equal to 
     * <code>0</code>, and less than or equal to the length of this 
     * string buffer. 
     *
     * @param      offset   the offset.
     * @param      b        a <code>double</code>.
     * @return     this string buffer.
     * @exception  StringIndexOutOfBoundsException  if the offset is invalid.
     * @see        java.lang.String#valueOf(double)
     * @see        java.lang.StringBuffer#insert(int, java.lang.String)
     * @see        java.lang.StringBuffer#length()
     * @since      JDK1.0
     */
    public StringBuffer insert(int offset, double d) {
	return insert(offset, String.valueOf(d));
    }

    /**
     * The character sequence contained in this string buffer is 
     * replaced by the reverse of the sequence. 
     *
     * @return  this string buffer.
     * @since   JDK1.0.2
     */
    public synchronized StringBuffer reverse() {
	copyWhenShared();
	int n = count - 1;
	for (int j = (n-1) >> 1; j >= 0; --j) {
	    char temp = value[j];
	    value[j] = value[n - j];
	    value[n - j] = temp;
	}
	return this;
    }

    /**
     * Converts to a string representing the data in this string buffer.
     * A new <code>String</code> object is allocated and initialized to 
     * contain the character sequence currently represented by this 
     * string buffer. This <code>String</code> is then returned. Subsequent 
     * changes to the string buffer do not affect the contents of the 
     * <code>String</code>. 
     *
     * @return  a string representation of the string buffer.
     * @since   JDK1.0
     */
    public String toString() {
	return new String(this);
    }

    //
    // The following two methods are needed by String to efficiently
    // convert a StringBuffer into a String.  They are not public.
    // They shouldn't be called by anyone but String.
    final void setShared() { shared = true; } 
    final char[] getValue() { return value; }
}
