@Test
public void testEquals() {

    new EqualsTester()
            .addEqualityGroup(new StringPoint(0, Instant.parse("2015-01-01T00:00:00Z").toEpochMilli(), "a"),
                              new StringPoint(0, Instant.parse("2015-01-01T00:00:00Z").toEpochMilli(), "a"))
            .addEqualityGroup(new StringPoint(1, Instant.parse("2015-01-01T00:15:00Z").toEpochMilli(), "b"),
                              new StringPoint(1, Instant.parse("2015-01-01T00:15:00Z").toEpochMilli(), "b"))
            .testEquals();
}