es截取指定的字段返回
SearchResponse response = client.prepareSearch(index_name).setTypes("lw_devices") .setFrom(start) .setSize(limit) .setQuery(boolQuery) .setFetchSource(new String[]{"d_id", "create_time"}, null) .addSort("create_time", SortOrder.DESC) .execute().actionGet();
这边只返回d_id和创建时间的字段