/** Confirm that the equals method can distinguish all the required fields. */
  public void testEquals() {
    StandardDialRange r1 = new StandardDialRange();
    StandardDialRange r2 = new StandardDialRange();
    assertTrue(r1.equals(r2));

    // lowerBound
    r1.setLowerBound(1.1);
    assertFalse(r1.equals(r2));
    r2.setLowerBound(1.1);
    assertTrue(r1.equals(r2));

    // upperBound
    r1.setUpperBound(11.1);
    assertFalse(r1.equals(r2));
    r2.setUpperBound(11.1);
    assertTrue(r1.equals(r2));

    // paint
    r1.setPaint(new GradientPaint(1.0f, 2.0f, Color.RED, 3.0f, 4.0f, Color.BLUE));
    assertFalse(r1.equals(r2));
    r2.setPaint(new GradientPaint(1.0f, 2.0f, Color.RED, 3.0f, 4.0f, Color.BLUE));
    assertTrue(r1.equals(r2));

    // check an inherited attribute
    r1.setVisible(false);
    assertFalse(r1.equals(r2));
    r2.setVisible(false);
    assertTrue(r1.equals(r2));
  }