Invalid type conversion Integer -> Double

[strkkk]

Jest version 6.3.1
ES version 6.4.2

Description:
After search result is back, if getHits() method changes type of result from Integer to Double

private JestClient client;
Class<Map<String, Object>> clazz = (Class<Map<String, Object>>) (Class) Map.class;
SearchResult result = client.execute(search);
System.out.println(result);
List<Map<String, Object>> foundSources =
        result.getHits(clazz).stream().map(hit -> hit.source).collect(Collectors.toList());
System.out.println(foundSources);

Output

Result: {"took":33,"timed_out":false,"_shards":{"total":5,"successful":5,"skipped":0,"failed":0},"hits":{"total":1,"max_score":null,"hits":[{"_index":"my_index","_type":"row","_id":"QgmKHHEBsa_VKQHeUjtF","_score":null,
"_source":{"mass":2041.9969,"length":20,"score":80,"mz":681.6733,},"sort":[80]}]}}, isSucceeded: true, response code: 200, error message: null
-------------------------------------^----------^-- integers


[{mass=2041.9969, length=20.0, score=80.0, mz=681.6733, es_metadata_id=QgmKHHEBsa_VKQHeUjtF}]
--------------------------^----------^-- doubles

fields "length" and "score" are integer in SearchResult, but converted to double if getHits is invoked.