org.bson.codecs.configuration.CodecConfigurationException

mongodb的聚合查询,里面包含枚举类型的查询时, 要转成String再做查询,否则会报:

org.bson.codecs.configuration.CodecConfigurationException: Can't find a codec for class  ...

记录一下.

例如下例中的SearchLogType.USER.toString()

    try {
      Criteria rightIntervalCR = Criteria.where("time").lt(rightIntervalDate);
      Criteria leftIntervalCR = Criteria.where("time").gte(leftIntervalDate);
      Criteria onlineCR = Criteria.where("type").is(SearchLogType.USER.toString());//只查询线上问的日志
      String[] groupUseFields = {"userid"};
      AggregationOperation matchOperation = new MatchOperation(leftIntervalCR.andOperator(onlineCR, rightIntervalCR));
      AggregationOperation groupOperation = new GroupOperation(Fields.fields(groupUseFields));
      AggregationOperation[] aggregationOperations = new AggregationOperation[2];
      aggregationOperations[0] = matchOperation;
      aggregationOperations[1] = groupOperation;
      Aggregation aggregation = Aggregation.newAggregation(aggregationOperations);
      AggregationResults<String> aggregationResults = mongoOperation.aggregate(aggregation, logCollectionName, String.class);
      List<String> useridList = aggregationResults.getMappedResults();
      if (useridList != null) {
        for (String userid : useridList) {
          JsonObject useridJsonObject = GsonFactory.getGsonClient().fromJson((String) userid, JsonObject.class);
          String useridStr = useridJsonObject.get("_id").getAsString();
 
        }
      }

    } catch (Exception e) {
      e.printStackTrace();
    }