Yes. we are passing JSON array as a whole string. Now I coded to convert back the whole string to JSON array as below and passing the request. Now i can able to retrieve the data.
public JsonArray getJsonArrayKey(String key) {
String keyWithoutDoubleQuotesAndBrackets= key.replaceAll("[\["\]]", “”);
String[] strArray = StringUtils.split(keyWithoutDoubleQuotesAndBrackets, “,”);
return JsonArray.from(strArray);
}