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();