@Override
    public int compareTo(COSObjectKey other)
    {
        return Long.compare(numberAndGeneration, other.numberAndGeneration);
    }
@Test
    void compareToInputNotNullOutputNotNull()
    {
        // Arrange
        final COSObjectKey objectUnderTest = new COSObjectKey(1L, 0);
        final COSObjectKey other = new COSObjectKey(9_999_999L, 0);

        // Act
        final int retvalNegative = objectUnderTest.compareTo(other);
        final int retvalPositive = other.compareTo(objectUnderTest);

        // Assert results
        assertEquals(-1, retvalNegative);
        assertEquals(1, retvalPositive);
    }