@Override
  public boolean equals(Object o) {
    if (!(o instanceof DateWritableV2)) {
      return false;
    }
    return compareTo((DateWritableV2) o) == 0;
  }
@return time in seconds corresponding to this DateWritableV2
serde/src/java/org/apache/hadoop/hive/serde2/io/DateWritableV2.java