static boolean allowCIDToUnicodeRange(Map.Entry<Integer, String> prev,
            Map.Entry<Integer, String> next)
    {
        if (prev == null || next == null)
        {
            return false;
        }
        return allowCodeRange(prev.getKey(), next.getKey())
                && allowDestinationRange(prev.getValue(), next.getValue());
    }
@Test
    void testAllowCIDToUnicodeRange()
    {
        Map.Entry<Integer, String> six = new AbstractMap.SimpleEntry<>(0x03FF, "6");
        Map.Entry<Integer, String> seven = new AbstractMap.SimpleEntry<>(0x0400,
                "7");
        Map.Entry<Integer, String> eight = new AbstractMap.SimpleEntry<>(0x0401,
                "8");

        assertFalse(ToUnicodeWriter.allowCIDToUnicodeRange(null, seven));
        assertFalse(ToUnicodeWriter.allowCIDToUnicodeRange(six, null));
        assertFalse(ToUnicodeWriter.allowCIDToUnicodeRange(six, seven));
        assertTrue(ToUnicodeWriter.allowCIDToUnicodeRange(seven, eight));
    }