public double length() {
        double result = 0;
        for (LineSegment segment : this.segments) {
            result += segment.length();
        }
        return result;
    }
@Test
    public void lengthTest() {
        Point point1 = new Point(0, 0);
        Point point2 = new Point(1, 0);
        Point point3 = new Point(1, 1);
        Point point4 = new Point(3, 1);

        LineString lineString = new LineString();
        lineString.segments.add(new LineSegment(point1, point2));
        lineString.segments.add(new LineSegment(point2, point3));
        lineString.segments.add(new LineSegment(point3, point4));

        Assert.assertEquals(4, lineString.length(), 0.0001);
        Assert.assertEquals(3, lineString.segments.size());
    }