@Test
  public void testAddZone() {
    System.out.println("Testing addZone() method...");

    System.out.print("\taddZone(null) must return false ...");
    assertFalse(empty_bp.addZone(null));
    System.out.println("OK");

    System.out.print("\taddZone(zone) must return true...");
    assertTrue(empty_bp.addZone(z1));
    System.out.println("OK");

    System.out.print("\taddZone(zone) must return true (multiple additions)...");
    assertTrue(empty_bp.addZone(z2));
    assertTrue(empty_bp.addZone(z3));
    System.out.println("OK");

    System.out.print("\tThe number of added zones are correct...");
    assertEquals("Different elements", empty_bp.getZones().size(), 3);
    System.out.println("OK");

    System.out.print("\tThe zones in the BorderPoint are the added ones...");
    assertEquals("Different elements", empty_bp.getZones().get(0), z1);
    assertEquals("Different elements", empty_bp.getZones().get(1), z2);
    assertEquals("Different elements", empty_bp.getZones().get(2), z3);
    System.out.println("OK");
  }
  @Test
  public void testGetZones() {
    System.out.println("Testing getZones() method...");

    System.out.print("\tgetZones() must return a list with the inserted zones...");
    assertEquals("Different elements", bp.getZones().size(), 3);
    assertEquals("Different elements", bp.getZones().get(0), z1);
    assertEquals("Different elements", bp.getZones().get(1), z2);
    assertEquals("Different elements", bp.getZones().get(2), z3);
    System.out.println("OK");
  }