How to get JSON string using JsonpRequestBuilder

Question

I am using the GWT JsonpRequestBuilder to issue a cross site REST request whose response is a JSON object.

The requestObject method callback parameter is JavaScriptObject. but I don’t want to implement JavaScriptObject, but just parse the JSON response directly. Is there anyway I can get the JSON string directly from any JavaScriptObject or JsonpRequestBuilder method?

Answer 1

If you want to use the com.google.gwt.json.JSON module (seriously, it’s better to write JavaScriptObject s, this JSON module is PITA for work), then you can simply wrap the returned JavaScriptObject in a JSONObject or JSONArray :

 new JSONObject(myJavaScriptObject) 

Answer 2

Use requestString instead of requestObject. Like this:

 JsonpRequestBuilder jsonp = new JsonpRequestBuilder(); jsonp.requestString(url, new AsyncCallback<String>() { ... 

This will return a string instead of JavaScriptObject. Then you can use JSONParser, for example:

 JSONObject value = (JSONObject)JSONParser.parseStrict(jsonString); Person person = new Person(); person.setName(value.get("Name").isString().stringValue()); 

Answer 3

@Gu Try to avoid quotes in generated json. For example, in server code, enter

  json = json.replace( "\"", "\\\"" ) 

Complete the resulting line as follows:

  String jsonCallback = request.getParameter("jsonpcallback") //or any other name StringBuilder response = new StringBuilder(); responseBody.append( jsonCallback ).append( "(\"" ).append( json ).append( "\");"); 

This code works for me on the client side:

  JsonpRequestBuilder jsonp = new JsonpRequestBuilder(); jsonp.setCallbackParam("jsonpcallback"); jsonp.requestString(....); 

PS I'm sorry. Not enough points to just comment on a given answer.