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

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

        // Assert result
        assertEquals(0, retval);
    }