如何将对象放于数组中

{

  "script": {

    "source": "if(ctx._source.containsKey(params.field)) {ctx._source.stu_contract.removeIf(item -> item.id==1);ctx._source.stu_contract.add(params.message)}",

    "lang": "painless",

    "params": {

      "field": "stu_contract",

      "message": {

        "name": "666",

        "id": 1

      }

    }

  }

}