stringbuffer.java

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     * @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) {
        int newcount = count + 1;
	if (newcount > value.length)
	    expandCapacity(newcount);
	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();
	int newcount = count + len;
	if (newcount > value.length)
	    expandCapacity(newcount);
	else if (shared)
	    copy();
	System.arraycopy(value, offset, value, offset + len, count - offset);
	str.getChars(0, len, value, offset);
	count = newcount;
	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;
	int newcount = count + len;
	if (newcount > value.length)
	    expandCapacity(newcount);
	else if (shared)
	    copy();
	System.arraycopy(value, offset, value, offset + len, count - offset);
	System.arraycopy(str, 0, value, offset, len);
	count = newcount;
	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) {
	int newcount = count + 1;
	if (newcount > value.length)
	    expandCapacity(newcount);
	else if (shared)
	    copy();
	System.arraycopy(value, offset, value, offset + 1, count - offset);
	value[offset] = c;
	count = newcount;
	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() {
	if (shared) copy();
	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; }

    /**
     * readObject is called to restore the state of the StringBuffer from
     * a stream.
     */
    private void readObject(java.io.ObjectInputStream s)
         throws java.io.IOException, ClassNotFoundException {
	s.defaultReadObject();
	value = (char[]) value.clone();
	shared = false;
    }
}