@Test
public void testHashCode() {

    assertFalse("Wrong equals implementation, different types are recognized as equals ", leOne.equals(new Integer(1)));
    assertFalse("Wrong equals implementation, different users are recognized as equals ", leOne.equals(leThree));
    assertFalse("Wrong equals implementation, null value is recognized as equals ", leOne.equals(null));
    assertTrue("Wrong equals implementation, same users are NOT recognized as equals ", leOne.equals(leOne));
    assertTrue("Wrong equals implementation, same users are NOT recognized as equals ", leOne.equals(sameAsLeOne));
}