Processing error message 'The function getJSONArray(JSONArray) does not exist' - arrays

Question

i am not sure why i am getting the error message 'The function getJSONArray(JSONArray) does not exist' when i run this sketch that uses a json query to Weather Underground. That comment seems illogical since Processing is recognising the id ref for the JSONArray.
The .json can be read here: http://api.wunderground.com/api/97a2805510de59e9/hourly/q/pws:IENGLAND274.json
Any thoughts? Thanks.
import com.francisli.processing.http.*;
HttpClient client;
String data;
com.francisli.processing.http.JSONObject weatherInfo;
JSONArray hourly_forecast;
int last = 0;
PImage img;
Float humidity = 50.2;
void setup() {
size(700, 700);
client = new HttpClient(this, "api.wunderground.com");
client.GET("/api/97a2805510de59e9/hourly/q/pws:IENGLAND274.json");
background(255);
}
void responseReceived(HttpRequest request, HttpResponse response) {
println(response.getContentAsString());
weatherInfo = response.getContentAsJSONObject();
JSONArray hourly_forecast = weatherInfo.getJSONArray(hourly_forecast);
}

Answer 1

There is no method called getJSONArray() that takes in a JSONArray as an argument.
The function should be used as JSONArray.getJSONArray(0) which gets the first array of elements in your JSON data. You can put this in a loop to get all of them.
Example (taken from: http://art.buffalo.edu/coursenotes/art380/reference/JSONArray_getJSONArray_.html):
// The following short JSON file called "data.json" is parsed
// in the code below. It must be in the project's "data" folder.
//
// [
// [
// { "name": "apple", "isFruit": true },
// { "name": "grape", "isFruit": true },
// { "name": "carrot", "isFruit": false }
// ],
// [
// { "name": "lettuce", "isFruit": false },
// { "name": "plum", "isFruit": true },
// { "name": "cinnamon", "isFruit": false }
// ]
// ]
JSONArray json;
void setup() {
json = loadJSONArray("data.json");
// Get the first array of elements
JSONArray values = json.getJSONArray(0);
for (int i = 0; i < values.size(); i++) {
JSONObject item = values.getJSONObject(i);
String name = item.getString("name");
boolean isFruit = item.getBoolean("isFruit");
println(name + ", " + isFruit);
}
}
// Sketch prints:
// apple, true
// grape, true
// carrot, false
Second problem with your code is that you're declaring hourly_forecast twice: once globally and once within the responseReceived() function. You probably want to remove JSONArray from hourly_forecast within the responseReceived() function.