Method append

java/Chapter 18/Question18_13/Rectangle.java:75–88

(String s)

     * underlying matrix of this Rectangle object is /not/ modified.
     */
    public Rectangle append(String s) {
        if (s.length() == length) {
            char temp[][] = new char[height + 1][length];
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < length; j++) {
                    temp[i][j] = matrix[i][j];
                }
            }
            s.getChars(0, length, temp[height], 0);

            return new Rectangle(length, height + 1, temp);
        }
        return null;
    }

    /* Print the rectangle out, row by row. */
    public void print() {