1. 코드
import org.json.JSONException; import org.json.JSONObject; import java.io.*; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; public class Exchange { private static final String HOST_URL = <API 주소>; public void get() { HttpURLConnection conn = null; JSONObject responseJson = null; try { URL url = new URL(HOST_URL); conn = (HttpURLConnection)url.openConnection(); conn.setConnectTimeout(5000); conn.setReadTimeout(5000); conn.setRequestMethod("GET"); //conn.setDoOutput(true); JSONObject commands = new JSONObject(); int responseCode = conn.getResponseCode(); if (responseCode == 400 || responseCode == 401 || responseCode == 500 ) { System.out.println(responseCode + " Error!"); } else { BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream())); StringBuilder sb = new StringBuilder(); String line = ""; while ((line = br.readLine()) != null) { sb.append(line); } responseJson = new JSONObject(sb.toString()); System.out.println(responseJson); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (JSONException e) { System.out.println("not JSON Format response"); e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } } }