@Test
    public void testGetSetDateUnspecifiedTimezone() {
        Metadata meta = new Metadata();

        // Set explictly without a timezone
        meta.set(TikaCoreProperties.CREATED, "1970-01-01T00:00:01");
        assertEquals("1970-01-01T00:00:01", meta.get(TikaCoreProperties.CREATED),
                "should return string without time zone specifier because zone is not known");

        // Now ask DateUtils to format for us without one
        meta.set(TikaCoreProperties.CREATED, DateUtils.formatDateUnknownTimezone(new Date(1000)));
        assertEquals("1970-01-01T00:00:01", meta.get(TikaCoreProperties.CREATED),
                "should return string without time zone specifier because zone is not known");
    }
Some documents, like jpegs, might have date in unspecified time zone
which should be handled like strings but verified to have parseable ISO 8601 format
tika-core/src/test/java/org/apache/tika/metadata/TestMetadata.java