@Test
public void testEqualsContract() {

    assertFalse("Wrong equals implementation, different types are recognized as equals ", one.equals(new Integer(1)));
    assertFalse("Wrong equals implementation, different objects are recognized as equals ", one.equals(two));
    assertFalse("Wrong equals implementation, null value is recognized as equals ", one.equals(null));
    assertTrue("Wrong equals implementation, same objects are NOT recognized as equals ", one.equals(sameRefAsOne));
    assertTrue("Wrong equals implementation, same objecst are NOT recognized as equals ", one.equals(sameAsOne));
}