Json.stringify outputs both index array and default

I am trying to stringify json input file using JSON.stringify method.

Input: [ { “serviceName”: “S1”, “operationName”: “GET /v1/path1/”, “requestJsonPaths”: [], “responseJsonPaths”: [] }, { “serviceName”: “S2”, “operationName”: “POST /v1/path2/”, “requestJsonPaths”: [], “responseJsonPaths”: [] } ]

Output of the stringify method has both indexed array and actual input as default.

{“0”: {“serviceName”:”S1″,”operationName”:”GET /v1/path1/”,”requestJsonPaths”:[],”responseJsonPaths”:[]},
“1”:{“serviceName”:”S2″,”operationName”:”POST /v1/path2/”,”requestJsonPaths”:[],”responseJsonPaths”:[]},
“default”:[{“serviceName”:”S1″,”operationName”:”GET /v1/path1/”,”requestJsonPaths”:[],”responseJsonPaths”:[]},{“serviceName”:”S2″,”operationName”:”POST /v1/path2/”,”requestJsonPaths”:[],”responseJsonPaths”:[]}]}

Above input will be placed in an file called sample.json and string conversion will be done as JSON.stringify(“sample.json”)

My expected output is similar to input instead of adding indexed array. Why stringify method adds index array ? Do I need to set any configuration?