@Test
public void testEquals() {

    Color color = new Color(1, 1, 1);
    Liquid liquid1 = new Liquid(1, SimulationConstants.MIN_TEMPERATURE, color);
    Liquid liquid2 = new Liquid(1, SimulationConstants.MIN_TEMPERATURE, color);
    assertTrue(liquid1.equals(liquid2));
    assertTrue(liquid2.equals(liquid1));
    assertFalse(liquid1.equals(null));
    assertFalse(liquid1.equals("test"));
    liquid2 = new Liquid(2, SimulationConstants.MIN_TEMPERATURE, color);
    assertFalse(liquid1.equals(liquid2));
    assertFalse(liquid2.equals(liquid1));
    liquid2 = new Liquid(1, SimulationConstants.MAX_TEMPERATURE, color);
    assertFalse(liquid1.equals(liquid2));
    assertFalse(liquid2.equals(liquid1));
}