@Test
    public void shouldConvertDateValues() {
        java.util.Date current = new java.util.Date();
        long currentMillis = current.getTime() % MILLIS_PER_DAY;
        long days = current.getTime() / MILLIS_PER_DAY;

        // java.util.Date - just copy
        java.util.Date d1 = Values.convertToDate(Date.SCHEMA, current);
        assertEquals(current, d1);

        // java.util.Date as a Timestamp - discard the day's milliseconds and keep the date
        java.util.Date currentDate = new java.util.Date(current.getTime() - currentMillis);
        d1 = Values.convertToDate(Timestamp.SCHEMA, currentDate);
        assertEquals(currentDate, d1);

        // ISO8601 strings - currently broken because tokenization breaks at colon

        // Days as string
        java.util.Date d3 = Values.convertToDate(Date.SCHEMA, Long.toString(days));
        assertEquals(currentDate, d3);

        // Days as long
        java.util.Date d4 = Values.convertToDate(Date.SCHEMA, days);
        assertEquals(currentDate, d4);
    }
This is technically invalid JSON, and we don't want to simply ignore the blank entry.
connect/api/src/test/java/org/apache/kafka/connect/data/ValuesTest.java