找不到请求操作的编解码器：[时间戳<->java.util.UUID]

Question

我在卡桑德拉（Cassandra）上有一张桌子，我正在尝试迭代并从中提取东西。我正在使用DataStax Java驱动程序3.1.0。

CREATE TABLE test (
  client_id int,
  process_id text,
  last_modified_date timestamp,
  PRIMARY KEY ((client_id), process_id)
)

以下是代码：

private List<MetaHolder> getMetaHolder() {
    List<MetaHolder> metaHolder = new ArrayList<>();
    String sql = "select * from test where client_id=1";
    try {
      BoundStatement bs = Cache.getInstance().getStatement(sql);
      bs.setConsistencyLevel(ConsistencyLevel.QUORUM);
      ResultSet res = session.execute(bs);
      Iterator<Row> rows = res.iterator();
      while (rows.hasNext()) {
        Row row = rows.next();
        String processId = row.getString("PROCESS_ID");
        // this line throws exception
        UUID lastModifiedDate = row.getUUID("LAST_MODIFIED_DATE");
        MetaHolder metadata =
            new MetaHolder(processId, lastModifiedDate);
        metaHolder.add(metadata);
      }
    } catch (Exception ex) {
      LOGGER.logError("error= ", ExceptionUtils.getStackTrace(ex));
    }
    return metaHolder;
}

以下是例外：

error= com.datastax.driver.core.exceptions.CodecNotFoundException: Codec not found for requested operation: [timestamp <-> java.util.UUID]

如果可能的话，我可以通过创建编解码器而不是在我的代码中使用uuid来使用jodatime？

Answer 1

更改以下代码

UUID lastModifiedDate = row.getUUID("LAST_MODIFIED_DATE");

to

Date lastModifiedDate = row.getTimestamp("LAST_MODIFIED_DATE");

您可以从日期获得Joda Datetime

DateTime lastModifiedDateTime = new DateTime(lastModifiedDate);