code: public void drawRect(int x, int y, int w, int h, Color color) {
          drawHorizontalLine(x, y, w, color);
          drawHorizontalLine(x, y + h - 1, w, color);
          drawVerticalLine(x, y, h, color);
          drawVerticalLine(x + w - 1, y, h, color);
      }
docs: Draw a rectangle