Unable to get Source filter while doing elastic search with spring boot class org.elasticsearch.search.builder.SearchSourceBuilder

@dadoonet thanks for follow up . document is look like below :-

{
  "took": 1,
  "timed_out": false,
  "_shards": {
    "total": 1,
    "successful": 1,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": {
      "value": 7875,
      "relation": "eq"
    },
    "max_score": 1,
    "hits": [
      {
        "_index": "contentsearch",
        "_type": "_doc",
        "_id": "kh4X33QBJG7M6evjj85r",
        "_score": 1,
        "_source": {
          "sub_content_download_count": null,
          "content_id": "104897",
          "soft_del": "0",
          "sub_content_property_3": "30.168000",
          "entity_id": "601506",
          "mount_point": null,
          "expiry_date": null,
          "task_id": "104899",
          "content_property_7": null,
          "content_property_27": null,
          "content_property_12": null,
          "content_property_17": null,
          "sub_content_property_9": null,
          "sub_content_property_21": null,
          "content_property_8": null,
          "sub_content_property_24": null,
          "content_property_37": null,
          "sub_content_property_29": null,
          "content_suspend": "F",
          "content_property_9": null,
          "content_property_48": "",
          "content_property_15": null,
          "content_property_13": null,
          "content_property_2": "Joko Joker",
          "content_property_36": null,
          "content_property_44": "",
          "order": 10000,
          "sub_content_id": "457419",
          "sub_content_property_30": null,
          "sub_content_property_28": null,
          "sub_content_property_1": "mp3",
          "content_property_19": null,
          "user_rating": null,
          "content_property_32": null,
          "content_property_30": null,
          "content_property_35": null,
          "content_property_42": "",
          "sub_content_property_15": null,
          "preview_image": "/opt/content_migration/Indosat.PNG",
          "content_property_21": null,
          "stage_id": "16",
          "sub_content_property_2": null,
          "content_property_11": null,
          "interface_id": null,
          "sub_content_property_17": null,
          "content_properties": null,
          "sub_content_property_11": null,
          "id": 457355,
          "tags": [
            "_contentsearch"
          ],
          "sub_content_property_25": null,
          "content_property_34": null,
          "sub_content_property_10": null,
          "content_download_count": null,
          "sub_content_property_12": null,
          "content_property_31": "PT. Virgo Ramayana",
          "sub_content_property_16": null,
          "content_property_46": "",
          "content_property_38": null,
          "content_property_29": "Bahasa",
          "sub_content_property_14": null,
          "sub_content_property_23": null,
          "upload_date": null,
          "content_property_25": null,
          "content_property_33": null,
          "sub_content_property_8": null,
          "location": "/cnt_repo02/rl/601/506/0/0000/0000/054.mp3",
          "content_property_26": "3",
          "sub_content_property_20": null,
          "sub_content_property_5": null,
          "content_property_18": null,
          "content_property_6": null,
          "content_property_22": null,
          "content_property_28": null,
          "last_change_date": null,
          "service_name": "popbarat_163_20191011",
          "content_property_4": null,
          "content_property_41": "",
          "content_property_40": null,
          "content_property_43": "",
          "category_search": "0",
          "sub_content_property_19": null,
          "content_category_map_id": "104899",
          "published_date": "2010-07-12T17:00:00.000Z",
          "is_preview": false,
          "description": "Transcoding",
          "content_owner": "601506",
          "sub_content_property_18": null,
          "access_count": "0",
          "status": "0",
          "category_id": "163",
          "sub_content_property_4": null,
          "content_property_24": null,
          "category_name": "popbarat",
          "sub_content_property_6": null,
          "content_property_45": "",
          "content_property_10": "Perkutrut Kentrut",
          "@version": "1",
          "sub_content_property_7": null,
          "sub_content_property_13": null,
          "content_property_5": "0630722",
          "service_id": "148",
          "content_property_47": "",
          "content_property_39": null,
          "sub_content_property_26": null,
          "content_property_23": "2900",
          "sub_content_properties": null,
          "timestamp": null,
          "content_property_3": null,
          "@timestamp": "2020-09-30T12:58:12.628Z",
          "content_property_49": "",
          "content_property_14": null,
          "content_property_1": null,
          "content_property_16": null,
          "content_property_20": null,
          "sub_content_property_27": null,
          "sub_content_property_22": null,
          "content_name": "Perkutrut Kentrut",
          "content_property_50": ""
        }
      }
    ]
  }
}

And arr containing new String{"stage_id","sub_content_property_1"}

exclude array will be null only.