@Test
public void testIntersectionWithCircle() {

  IDirectPosition p1 = new DirectPosition(0.0, 0.0);
  IDirectPosition p2 = new DirectPosition(10.0, 0.0);
  IDirectPosition p3 = new DirectPosition(5.0, 0.0);
  IDirectPosition p4 = new DirectPosition(15.0, 0.0);
  Segment segment = new Segment(p1, p2);
  System.out.println(segment.getCoefA());
  System.out.println(segment.getCoefB());
  System.out.println(segment.getCoefC());
  Set<IDirectPosition> inter = segment.intersectionWithCircle(p2, 5.0);
  Iterator<IDirectPosition> iter = inter.iterator();
  IDirectPosition inter1 = iter.next();
  IDirectPosition inter2 = iter.next();
  Assert.assertTrue(inter1.equals(p3) || inter2.equals(p3));
  Assert.assertTrue(inter1.equals(p4) || inter2.equals(p4));
}