java - 从 Play Framework Controller 返回 JSON 字符串

Question

我正在从客户端发出 ajax POST 请求。我的 Play Framework Controller 向跨域服务器发出请求，该服务器返回 JSON。然后我想将此 JSON 转发给客户端。当我调用Promise<JsonNode>.toString()时，看来我收到了一个内存地址。如何将实际的 JSON 返回给客户端？

    public static Result addVenue() {

      final Map<String, String[]> values = request().body().asFormUrlEncoded();
      String queryString = values.get("venueName")[0]  + ",+" + values.get("venueAddress")[0] + ",+" + values.get("venueCity")[0] + ",+" + values.get("venueState")[0] + "+" + values.get("venueZip")[0];
      String queryURL = "https://maps.googleapis.com/maps/api/place/textsearch/json?query=" + queryString + "&key=" + "AIzaSyD1xSgKUnEZ_tM7qzcEAeM-SJBxPFhIpaU";
      queryURL = queryURL.replaceAll(" ", "+");

      Promise<JsonNode> jsonPromise = WS.url(queryURL).get().map(
              new Function<WSResponse, JsonNode>() {
                  public JsonNode apply(WSResponse response) {
                      JsonNode json = response.asJson();
                      return json;
                  }
              }
      );

      response().setHeader("Access-Control-Allow-Origin", "*");
      response().setHeader("Allow", "*");
      response().setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, DELETE, OPTIONS");
      response().setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Referer, User-Agent");
      return ok(jsonPromise.toString());
}

Answer 1

返回结果 promise :

public static Promise<Result> addVenue() {
    return WS.url(URL).get().map((response) -> {
        return ok(response.asJson());
    });
}