@Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof MultiValuedTimestamp)) {
            return false;
        }
        MultiValuedTimestamp that = (MultiValuedTimestamp) obj;
        return Objects.equals(this.value1, that.value1) &&
                Objects.equals(this.value2, that.value2);
    }
@Test
    public void testEquals() {
        new EqualsTester()
                .addEqualityGroup(stats1, stats1)
                .addEqualityGroup(stats2)
                .testEquals();
    }