AbstractStringBuilder() 
{

}

This no-arg constructor is necessary for serialization of subclasses.

 AbstractStringBuilder(int capacity) 
{
        value = new char[capacity];
}

Creates an AbstractStringBuilder of the specified capacity.

 public AbstractStringBuilder append(Object obj) 
{
        return append(String.valueOf(obj));
}

Appends the string representation of the Object argument.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this sequence.

 public AbstractStringBuilder append(String str) 
{
        if (str == null) str = "null";
        int len = str.length();
        if (len == 0) return this;
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        str.getChars(0, len, value, count);
        count = newCount;
        return this;
}

Appends the specified string to this character sequence.

The characters of the String argument are appended, in order, increasing the length of this sequence by the length of the argument. If str is null, then the four characters "null" are appended.

Let n be the length of this character sequence just prior to execution of the append method. Then the character at index k in the new character sequence is equal to the character at index k in the old character sequence, if k is less than n; otherwise, it is equal to the character at index k-n in the argument str.

 public AbstractStringBuilder append(StringBuffer sb) 
{
        if (sb == null)
            return append("null");
        int len = sb.length();
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        sb.getChars(0, len, value, count);
        count = newCount;
        return this;
}

 public AbstractStringBuilder append(CharSequence s) 
{
        if (s == null)
            s = "null";
        if (s instanceof String)
            return this.append((String)s);
        if (s instanceof StringBuffer)
            return this.append((StringBuffer)s);
        return this.append(s, 0, s.length());
}

 public AbstractStringBuilder append(char[] str) 
{
        int newCount = count + str.length;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(str, 0, value, count, str.length);
        count = newCount;
        return this;
}

Appends the string representation of the char array argument to this sequence.

The characters of the array argument are appended, in order, to the contents of this sequence. The length of this sequence increases by the length of the argument.

The overall effect is exactly as if the argument were converted to a string by the method String#valueOf(char[]) and the characters of that string were then appended to this character sequence.

 public AbstractStringBuilder append(boolean b) 
{
        if (b) {
            int newCount = count + 4;
            if (newCount  > value.length)
                expandCapacity(newCount);
            value[count++] = 't";
            value[count++] = 'r";
            value[count++] = 'u";
            value[count++] = 'e";
        } else {
            int newCount = count + 5;
            if (newCount  > value.length)
                expandCapacity(newCount);
            value[count++] = 'f";
            value[count++] = 'a";
            value[count++] = 'l";
            value[count++] = 's";
            value[count++] = 'e";
        }
        return this;
}

Appends the string representation of the boolean argument to the sequence.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this sequence.

 public AbstractStringBuilder append(char c) 
{
        int newCount = count + 1;
        if (newCount  > value.length)
            expandCapacity(newCount);
        value[count++] = c;
        return this;
}

Appends the string representation of the char argument to this sequence.

The argument is appended to the contents of this sequence. The length of this sequence increases by 1.

The overall effect is exactly as if the argument were converted to a string by the method String#valueOf(char) and the character in that string were then appended to this character sequence.

 public AbstractStringBuilder append(int i) 
{
        if (i == Integer.MIN_VALUE) {
            append("-2147483648");
            return this;
        }
        int appendedLength = (i <  0) ? Integer.stringSize(-i) + 1
                                     : Integer.stringSize(i);
        int spaceNeeded = count + appendedLength;
        if (spaceNeeded  > value.length)
            expandCapacity(spaceNeeded);
        Integer.getChars(i, spaceNeeded, value);
        count = spaceNeeded;
        return this;
}

Appends the string representation of the int argument to this sequence.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this sequence.

 public AbstractStringBuilder append(long l) 
{
        if (l == Long.MIN_VALUE) {
            append("-9223372036854775808");
            return this;
        }
        int appendedLength = (l <  0) ? Long.stringSize(-l) + 1
                                     : Long.stringSize(l);
        int spaceNeeded = count + appendedLength;
        if (spaceNeeded  > value.length)
            expandCapacity(spaceNeeded);
        Long.getChars(l, spaceNeeded, value);
        count = spaceNeeded;
        return this;
}

Appends the string representation of the long argument to this sequence.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this sequence.

 public AbstractStringBuilder append(float f) 
{
        new FloatingDecimal(f).appendTo(this);
        return this;
}

Appends the string representation of the float argument to this sequence.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this string sequence.

 public AbstractStringBuilder append(double d) 
{
        new FloatingDecimal(d).appendTo(this);
        return this;
}

Appends the string representation of the double argument to this sequence.

The argument is converted to a string as if by the method String.valueOf, and the characters of that string are then appended to this sequence.

 public AbstractStringBuilder append(CharSequence s,
    int start,
    int end) 
{
        if (s == null)
            s = "null";
        if ((start <  0) || (end <  0) || (start  > end) || (end  > s.length()))
            throw new IndexOutOfBoundsException(
                "start " + start + ", end " + end + ", s.length() "
                + s.length());
        int len = end - start;
        if (len == 0)
            return this;
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        for (int i=start; i< end; i++)
            value[count++] = s.charAt(i);
        count = newCount;
        return this;
}

Appends a subsequence of the specified CharSequence to this sequence.

Characters of the argument s, starting at index start, are appended, in order, to the contents of this sequence up to the (exclusive) index end. The length of this sequence is increased by the value of end - start.

Let n be the length of this character sequence just prior to execution of the append method. Then the character at index k in this character sequence becomes equal to the character at index k in this sequence, if k is less than n; otherwise, it is equal to the character at index k+start-n in the argument s.

If s is null, then this method appends characters as if the s parameter was a sequence containing the four characters "null".

 public AbstractStringBuilder append(char[] str,
    int offset,
    int len) 
{
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(str, offset, value, count, len);
        count = newCount;
        return this;
}

Appends the string representation of a subarray of the char array argument to this sequence.

Characters of the char array str, starting at index offset, are appended, in order, to the contents of this sequence. The length of this sequence increases by the value of len.

The overall effect is exactly as if the arguments were converted to a string by the method String#valueOf(char[],int,int) and the characters of that string were then appended to this character sequence.

 public AbstractStringBuilder appendCodePoint(int codePoint) 
{
        if (!Character.isValidCodePoint(codePoint)) {
            throw new IllegalArgumentException();
        }
        int n = 1;
        if (codePoint  >= Character.MIN_SUPPLEMENTARY_CODE_POINT) {
            n++;
        }
        int newCount = count + n;
        if (newCount  > value.length) {
            expandCapacity(newCount);
        }
        if (n == 1) {
            value[count++] = (char) codePoint;
        } else {
            Character.toSurrogates(codePoint, value, count);
            count += n;
        }
        return this;
}

Appends the string representation of the codePoint argument to this sequence.

The argument is appended to the contents of this sequence. The length of this sequence increases by Character.charCount(codePoint) .

The overall effect is exactly as if the argument were converted to a char array by the method Character#toChars(int) and the character in that array were then appended to this character sequence.

 public int capacity() 
{
        return value.length;
}

Returns the current capacity. The capacity is the amount of storage available for newly inserted characters, beyond which an allocation will occur.

 public char charAt(int index) 
{
        if ((index <  0) || (index  >= count))
            throw new StringIndexOutOfBoundsException(index);
        return value[index];
}

Returns the char value in this sequence at the specified index. The first char value is at index 0, the next at index 1, and so on, as in array indexing.

The index argument must be greater than or equal to 0, and less than the length of this sequence.

If the char value specified by the index is a surrogate, the surrogate value is returned.

 public int codePointAt(int index) 
{
        if ((index <  0) || (index  >= count)) {
            throw new StringIndexOutOfBoundsException(index);
        }
        return Character.codePointAt(value, index);
}

Returns the character (Unicode code point) at the specified index. The index refers to char values (Unicode code units) and ranges from 0 to #length() - 1.

If the char value specified at the given index is in the high-surrogate range, the following index is less than the length of this sequence, and the char value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char value at the given index is returned.

 public int codePointBefore(int index) 
{
        int i = index - 1;
        if ((i <  0) || (i  >= count)) {
            throw new StringIndexOutOfBoundsException(index);
        }
        return Character.codePointBefore(value, index);
}

Returns the character (Unicode code point) before the specified index. The index refers to char values (Unicode code units) and ranges from 1 to #length() .

If the char value at (index - 1) is in the low-surrogate range, (index - 2) is not negative, and the char value at (index - 2) is in the high-surrogate range, then the supplementary code point value of the surrogate pair is returned. If the char value at index - 1 is an unpaired low-surrogate or a high-surrogate, the surrogate value is returned.

 public int codePointCount(int beginIndex,
    int endIndex) 
{
        if (beginIndex <  0 || endIndex  > count || beginIndex  > endIndex) {
            throw new IndexOutOfBoundsException();
        }
        return Character.codePointCountImpl(value, beginIndex, endIndex-beginIndex);
}

Returns the number of Unicode code points in the specified text range of this sequence. The text range begins at the specified beginIndex and extends to the char at index endIndex - 1. Thus the length (in chars) of the text range is endIndex-beginIndex. Unpaired surrogates within this sequence count as one code point each.

 public AbstractStringBuilder delete(int start,
    int end) 
{
        if (start <  0)
            throw new StringIndexOutOfBoundsException(start);
        if (end  > count)
            end = count;
        if (start  > end)
            throw new StringIndexOutOfBoundsException();
        int len = end - start;
        if (len  > 0) {
            System.arraycopy(value, start+len, value, start, count-end);
            count -= len;
        }
        return this;
}

Removes the characters in a substring of this sequence. The substring begins at the specified start and extends to the character at index end - 1 or to the end of the sequence if no such character exists. If start is equal to end, no changes are made.

 public AbstractStringBuilder deleteCharAt(int index) 
{
        if ((index <  0) || (index  >= count))
            throw new StringIndexOutOfBoundsException(index);
        System.arraycopy(value, index+1, value, index, count-index-1);
        count--;
        return this;
}

Removes the char at the specified position in this sequence. This sequence is shortened by one char.

Note: If the character at the given index is a supplementary character, this method does not remove the entire character. If correct handling of supplementary characters is required, determine the number of chars to remove by calling Character.charCount(thisSequence.codePointAt(index)), where thisSequence is this sequence.

 public  void ensureCapacity(int minimumCapacity) 
{
        if (minimumCapacity  > value.length) {
            expandCapacity(minimumCapacity);
        }
}

Ensures that the capacity is at least equal to the specified minimum. If the current capacity is less than the argument, then a new internal array is allocated with greater capacity. The new capacity is the larger of:
• The minimumCapacity argument.
• Twice the old capacity, plus 2.
If the minimumCapacity argument is nonpositive, this method takes no action and simply returns.

  void expandCapacity(int minimumCapacity) 
{
        int newCapacity = (value.length + 1) * 2;
        if (newCapacity <  0) {
            newCapacity = Integer.MAX_VALUE;
        } else if (minimumCapacity  > newCapacity) {
            newCapacity = minimumCapacity;
        }
        value = Arrays.copyOf(value, newCapacity);
}

This implements the expansion semantics of ensureCapacity with no size check or synchronization.

 public  void getChars(int srcBegin,
    int srcEnd,
    char[] dst,
    int dstBegin) 
{
        if (srcBegin <  0)
            throw new StringIndexOutOfBoundsException(srcBegin);
        if ((srcEnd <  0) || (srcEnd  > count))
            throw new StringIndexOutOfBoundsException(srcEnd);
        if (srcBegin  > srcEnd)
            throw new StringIndexOutOfBoundsException("srcBegin  > srcEnd");
        System.arraycopy(value, srcBegin, dst, dstBegin, srcEnd - srcBegin);
}

Characters are copied from this sequence into the destination character array dst. The first character to be copied is at index srcBegin; the last character to be copied is at index srcEnd-1. The total number of characters to be copied is srcEnd-srcBegin. The characters are copied into the subarray of dst starting at index dstBegin and ending at index:

dstbegin + (srcEnd-srcBegin) - 1

 final char[] getValue() 
{
        return value;
}

Needed by String for the contentEquals method.

 public int indexOf(String str) 
{
        return indexOf(str, 0);
}

Returns the index within this string of the first occurrence of the specified substring. The integer returned is the smallest value k such that:

this.toString().startsWith(str, k)

is true.

 public int indexOf(String str,
    int fromIndex) 
{
        return String.indexOf(value, 0, count,
                              str.toCharArray(), 0, str.length(), fromIndex);
}

Returns the index within this string of the first occurrence of the specified substring, starting at the specified index. The integer returned is the smallest value k for which:

k >= Math.min(fromIndex, str.length()) &&
this.toString().startsWith(str, k)

If no such value of k exists, then -1 is returned.

 public AbstractStringBuilder insert(int offset,
    Object obj) 
{
        return insert(offset, String.valueOf(obj));
}

Inserts the string representation of the Object argument into this character sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    String str) 
{
        if ((offset <  0) || (offset  > length()))
            throw new StringIndexOutOfBoundsException(offset);
        if (str == null)
            str = "null";
        int len = str.length();
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(value, offset, value, offset + len, count - offset);
        str.getChars(value, offset);
        count = newCount;
        return this;
}

Inserts the string into this character sequence.

The characters of the String argument are inserted, in order, into this sequence at the indicated offset, moving up any characters originally above that position and increasing the length of this sequence by the length of the argument. If str is null, then the four characters "null" are inserted into this sequence.

The character at index k in the new character sequence is equal to:

• the character at index k in the old character sequence, if k is less than offset
• the character at index k-offset in the argument str, if k is not less than offset but is less than offset+str.length()
• the character at index k-str.length() in the old character sequence, if k is not less than offset+str.length()

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    char[] str) 
{
        if ((offset <  0) || (offset  > length()))
            throw new StringIndexOutOfBoundsException(offset);
        int len = str.length;
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        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 char array argument into this sequence.

The characters of the array argument are inserted into the contents of this sequence at the position indicated by offset. The length of this sequence increases by the length of the argument.

The overall effect is exactly as if the argument were converted to a string by the method String#valueOf(char[]) and the characters of that string were then inserted into this character sequence at the position indicated by offset.

 public AbstractStringBuilder insert(int dstOffset,
    CharSequence s) 
{
        if (s == null)
            s = "null";
        if (s instanceof String)
            return this.insert(dstOffset, (String)s);
        return this.insert(dstOffset, s, 0, s.length());
}

Inserts the specified CharSequence into this sequence.

The characters of the CharSequence argument are inserted, in order, into this sequence at the indicated offset, moving up any characters originally above that position and increasing the length of this sequence by the length of the argument s.

The result of this method is exactly the same as if it were an invocation of this object's insert(dstOffset, s, 0, s.length()) method.

If s is null, then the four characters "null" are inserted into this sequence.

 public AbstractStringBuilder insert(int offset,
    boolean b) 
{
        return insert(offset, String.valueOf(b));
}

Inserts the string representation of the boolean argument into this sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    char c) 
{
        int newCount = count + 1;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(value, offset, value, offset + 1, count - offset);
        value[offset] = c;
        count = newCount;
        return this;
}

Inserts the string representation of the char argument into this sequence.

The second argument is inserted into the contents of this sequence at the position indicated by offset. The length of this sequence increases by one.

The overall effect is exactly as if the argument were converted to a string by the method String#valueOf(char) and the character in that string were then inserted into this character sequence at the position indicated by offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    int i) 
{
        return insert(offset, String.valueOf(i));
}

Inserts the string representation of the second int argument into this sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    long l) 
{
        return insert(offset, String.valueOf(l));
}

Inserts the string representation of the long argument into this sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the position indicated by offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    float f) 
{
        return insert(offset, String.valueOf(f));
}

Inserts the string representation of the float argument into this sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int offset,
    double d) 
{
        return insert(offset, String.valueOf(d));
}

Inserts the string representation of the double argument into this sequence.

The second argument is converted to a string as if by the method String.valueOf, and the characters of that string are then inserted into this sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

 public AbstractStringBuilder insert(int index,
    char[] str,
    int offset,
    int len) 
{
        if ((index <  0) || (index  > length()))
            throw new StringIndexOutOfBoundsException(index);
        if ((offset <  0) || (len <  0) || (offset  > str.length - len))
            throw new StringIndexOutOfBoundsException(
                "offset " + offset + ", len " + len + ", str.length "
                + str.length);
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(value, index, value, index + len, count - index);
        System.arraycopy(str, offset, value, index, len);
        count = newCount;
        return this;
}

Inserts the string representation of a subarray of the str array argument into this sequence. The subarray begins at the specified offset and extends len chars. The characters of the subarray are inserted into this sequence at the position indicated by index. The length of this sequence increases by len chars.

 public AbstractStringBuilder insert(int dstOffset,
    CharSequence s,
    int start,
    int end) 
{
        if (s == null)
            s = "null";
        if ((dstOffset <  0) || (dstOffset  > this.length()))
            throw new IndexOutOfBoundsException("dstOffset "+dstOffset);
        if ((start <  0) || (end <  0) || (start  > end) || (end  > s.length()))
            throw new IndexOutOfBoundsException(
                "start " + start + ", end " + end + ", s.length() "
                + s.length());
        int len = end - start;
        if (len == 0)
            return this;
        int newCount = count + len;
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(value, dstOffset, value, dstOffset + len,
                         count - dstOffset);
        for (int i=start; i< end; i++)
            value[dstOffset++] = s.charAt(i);
        count = newCount;
        return this;
}

Inserts a subsequence of the specified CharSequence into this sequence.

The subsequence of the argument s specified by start and end are inserted, in order, into this sequence at the specified destination offset, moving up any characters originally above that position. The length of this sequence is increased by end - start.

The character at index k in this sequence becomes equal to:

• the character at index k in this sequence, if k is less than dstOffset
• the character at index k+start-dstOffset in the argument s, if k is greater than or equal to dstOffset but is less than dstOffset+end-start
• the character at index k-(end-start) in this sequence, if k is greater than or equal to dstOffset+end-start

The dstOffset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

The start argument must be nonnegative, and not greater than end.

The end argument must be greater than or equal to start, and less than or equal to the length of s.

If s is null, then this method inserts characters as if the s parameter was a sequence containing the four characters "null".

 public int lastIndexOf(String str) 
{
        return lastIndexOf(str, count);
}

Returns the index within this string of the rightmost occurrence of the specified substring. The rightmost empty string "" is considered to occur at the index value this.length(). The returned index is the largest value k such that

this.toString().startsWith(str, k)

is true.

 public int lastIndexOf(String str,
    int fromIndex) 
{
        return String.lastIndexOf(value, 0, count,
                              str.toCharArray(), 0, str.length(), fromIndex);
}

Returns the index within this string of the last occurrence of the specified substring. The integer returned is the largest value k such that:

k <= Math.min(fromIndex, str.length()) &&
this.toString().startsWith(str, k)

If no such value of k exists, then -1 is returned.

 public int length() 
{
        return count;
}

Returns the length (character count).

 public int offsetByCodePoints(int index,
    int codePointOffset) 
{
        if (index <  0 || index  > count) {
            throw new IndexOutOfBoundsException();
        }
        return Character.offsetByCodePointsImpl(value, 0, count,
                                                index, codePointOffset);
}

Returns the index within this sequence that is offset from the given index by codePointOffset code points. Unpaired surrogates within the text range given by index and codePointOffset count as one code point each.

 public AbstractStringBuilder replace(int start,
    int end,
    String str) 
{
        if (start <  0)
            throw new StringIndexOutOfBoundsException(start);
        if (start  > count)
            throw new StringIndexOutOfBoundsException("start  > length()");
        if (start  > end)
            throw new StringIndexOutOfBoundsException("start  > end");
        if (end  > count)
            end = count;
        int len = str.length();
        int newCount = count + len - (end - start);
        if (newCount  > value.length)
            expandCapacity(newCount);
        System.arraycopy(value, end, value, start + len, count - end);
        str.getChars(value, start);
        count = newCount;
        return this;
}

Replaces the characters in a substring of this sequence with characters in the specified String. The substring begins at the specified start and extends to the character at index end - 1 or to the end of the sequence if no such character exists. First the characters in the substring are removed and then the specified String is inserted at start. (This sequence will be lengthened to accommodate the specified String if necessary.)

 public AbstractStringBuilder reverse() 
{
        boolean hasSurrogate = false;
        int n = count - 1;
        for (int j = (n-1)  > > 1; j  >= 0; --j) {
            char temp = value[j];
            char temp2 = value[n - j];
            if (!hasSurrogate) {
                hasSurrogate = (temp  >= Character.MIN_SURROGATE && temp < = Character.MAX_SURROGATE)
                    || (temp2  >= Character.MIN_SURROGATE && temp2 < = Character.MAX_SURROGATE);
            }
            value[j] = temp2;
            value[n - j] = temp;
        }
        if (hasSurrogate) {
            // Reverse back all valid surrogate pairs
            for (int i = 0; i <  count - 1; i++) {
                char c2 = value[i];
                if (Character.isLowSurrogate(c2)) {
                    char c1 = value[i + 1];
                    if (Character.isHighSurrogate(c1)) {
                        value[i++] = c1;
                        value[i] = c2;
                    }
                }
            }
        }
        return this;
}

Causes this character sequence to be replaced by the reverse of the sequence. If there are any surrogate pairs included in the sequence, these are treated as single characters for the reverse operation. Thus, the order of the high-low surrogates is never reversed. Let n be the character length of this character sequence (not the length in char values) just prior to execution of the reverse method. Then the character at index k in the new character sequence is equal to the character at index n-k-1 in the old character sequence.

Note that the reverse operation may result in producing surrogate pairs that were unpaired low-surrogates and high-surrogates before the operation. For example, reversing "\uDC00\uD800" produces "\uD800\uDC00" which is a valid surrogate pair.

 public  void setCharAt(int index,
    char ch) 
{
        if ((index <  0) || (index  >= count))
            throw new StringIndexOutOfBoundsException(index);
        value[index] = ch;
}

The character at the specified index is set to ch. This sequence is altered to represent a new character sequence that is identical to the old character sequence, except that it contains the character ch at position index.

The index argument must be greater than or equal to 0, and less than the length of this sequence.

 public  void setLength(int newLength) 
{
        if (newLength <  0)
            throw new StringIndexOutOfBoundsException(newLength);
        if (newLength  > value.length)
            expandCapacity(newLength);
        if (count <  newLength) {
            for (; count <  newLength; count++)
                value[count] = '\0";
        } else {
            count = newLength;
        }
}

Sets the length of the character sequence. The sequence is changed to a new character sequence whose length is specified by the argument. For every nonnegative index k less than newLength, the character at index k in the new character sequence is the same as the character at index k in the old sequence if k is less than the length of the old character sequence; otherwise, it is the null character '\u0000'. In other words, if the newLength argument is less than the current length, the length is changed to the specified length.

If the newLength argument is greater than or equal to the current length, sufficient null characters ('\u0000') are appended so that length becomes the newLength argument.

The newLength argument must be greater than or equal to 0.

 public CharSequence subSequence(int start,
    int end) 
{
        return substring(start, end);
}

Returns a new character sequence that is a subsequence of this sequence.

An invocation of this method of the form

sb.subSequence(begin, end)

behaves in exactly the same way as the invocation

sb.substring(begin, end)

This method is provided so that this class can implement the CharSequence interface.

 public String substring(int start) 
{
        return substring(start, count);
}

Returns a new String that contains a subsequence of characters currently contained in this character sequence. The substring begins at the specified index and extends to the end of this sequence.

 public String substring(int start,
    int end) 
{
        if (start <  0)
            throw new StringIndexOutOfBoundsException(start);
        if (end  > count)
            throw new StringIndexOutOfBoundsException(end);
        if (start  > end)
            throw new StringIndexOutOfBoundsException(end - start);
        return new String(value, start, end - start);
}

Returns a new String that contains a subsequence of characters currently contained in this sequence. The substring begins at the specified start and extends to the character at index end - 1.

 abstract public String toString()
Returns a string representing the data in this sequence.
A new String object is allocated and initialized to
contain the character sequence currently represented by this
object. This String is then returned. Subsequent
changes to this sequence do not affect the contents of the
String.

 public  void trimToSize() 
{
        if (count <  value.length) {
            value = Arrays.copyOf(value, count);
        }
}

Attempts to reduce storage used for the character sequence. If the buffer is larger than necessary to hold its current sequence of characters, then it may be resized to become more space efficient. Calling this method may, but is not required to, affect the value returned by a subsequent call to the #capacity() method.