How to format the output to proper json format?

Question

I have a dynamic web project where in my jsp page, on clicking a form, it retrieves the data from elasticsearch and displays in the UI in proper json format as Key:value pair.

  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    String start = request.getParameter("start");
    String end = request.getParameter("end");

  String line1;
  StringBuffer jsonString1 = new StringBuffer();


  try {

      URL url1 = new URL("http://localhost:9200/indexname/_search?filter_path=hits.hits._source&pretty=1&size=100000");

      String payload1 = "{\"query\":{\"filtered\":{\"filter\":{\"range\":{\"Date\":{\"lte\":\""+end+"\",\"gte\":\""+start+"\"}}}}},\"_source\":{\"include\":[\"ID\",\"Name\",\"Status\",\"Date\"]}}";

      HttpURLConnection connection1 = (HttpURLConnection) url1.openConnection();

      connection1.setDoInput(true);
      connection1.setDoOutput(true);
      connection1.setRequestMethod("POST");
      connection1.setRequestProperty("Accept", "application/json");
      connection1.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
      OutputStreamWriter writer1 = new OutputStreamWriter(connection1.getOutputStream(), "UTF-8");
      writer1.write(payload1);
      writer1.close();

      BufferedReader br1 = new BufferedReader(new InputStreamReader(connection1.getInputStream()));
      while ((line1 = br1.readLine()) != null) {
           jsonString1.append(line1);  
      }

      br1.close();
      file1.close();
      connection1.disconnect();             

  } catch (Exception e) {
        throw new RuntimeException(e.getMessage());
}

  response.setContentType("application/json");

 // JSONObject jsonObj = new JSONObject(jsonString1.toString()); //JSONObject cannot be resolved to a type error is getting displayed.
  //System.out.println("---------------------------");
 // System.out.println(jsonObj);

    PrintWriter out = response.getWriter();
    out.print(jsonString1); //Here instead of String buffer I want to send a json object or an arraylist which outputs just the key value pair by removing all unwanted characters.
    out.flush();
    out.close();
 }

In m HTML, on performing a Submit operation, it displays something like this :

{  "hits" : {    "hits" : [ {      "_source":{"ID":"123","Status":"false","Name":"ABC_123","Date":"2010-08-16T11:07:48"}    }, {      "_source":{"ID":"124","Status":"false","Name":"ABC_678","Date":"2010-08-16T12:00:12"}    }, {      "_source":{"ID":"125","Status":"true","Name":"FGH_122","Date":"2010-08-16T12:01:48"}    }, {      "_source":{"ID":"126","Status":"false","Name":"TYT_333","Date":"2010-08-16T12:06:48"}    }, {      "_source":{"ID":"127","Status":"false","Name":"CVF_230","Date":"2010-08-16T12:07:18"}    }, {      "_source":{"ID":"128","Status":"true","Name":"AWE_101","Date":"2010-08-16T12:03:48"}    }, {      "_source":{"ID":"129","Status":"true","Name":"WEC_299","Date":"2010-08-16T12:07:29"}    } ]  }}

Instead, I want to display in my UI some alert box or something like that where it displays

{"ID":"123","Status":"false","Name":"ABC_123","Date":"2010-08-16T11:07:48"},
{"ID":"124","Status":"false","Name":"ABC_678","Date":"2010-08-16T12:00:12"},
{"ID":"125","Status":"true","Name":"FGH_122","Date":"2010-08-16T12:01:48"}

etc....

Any idea on how I can achieve this? Please advice. Thanks.

Answer 1

Do a classic iteration of your json string, before PrintWriter step

String jsonString1 = "{ \"hits\": {     \"hits\": [{            \"_source\": {              \"ID\": \"123\",                \"Status\": \"false\",              \"Name\": \"ABC_123\",              \"Date\": \"2010-08-16T11:07:48\"           }       }, {            \"_source\": {              \"ID\": \"124\",                \"Status\": \"false\",              \"Name\": \"ABC_678\",              \"Date\": \"2010-08-16T12:00:12\"           }       }, {            \"_source\": {              \"ID\": \"125\",                \"Status\": \"true\",               \"Name\": \"FGH_122\",              \"Date\": \"2010-08-16T12:01:48\"           }       }, {            \"_source\": {              \"ID\": \"126\",                \"Status\": \"false\",              \"Name\": \"TYT_333\",              \"Date\": \"2010-08-16T12:06:48\"           }       }, {            \"_source\": {              \"ID\": \"127\",                \"Status\": \"false\",              \"Name\": \"CVF_230\",              \"Date\": \"2010-08-16T12:07:18\"           }       }, {            \"_source\": {              \"ID\": \"128\",                \"Status\": \"true\",               \"Name\": \"AWE_101\",              \"Date\": \"2010-08-16T12:03:48\"           }       }, {            \"_source\": {              \"ID\": \"129\",                \"Status\": \"true\",               \"Name\": \"WEC_299\",              \"Date\": \"2010-08-16T12:07:29\"           }       }]  }}";
JSONObject jsonObj = new JSONObject(jsonString1);
JSONObject c = jsonObj.getJSONObject("hits");
JSONArray c1 = c.getJSONArray("hits");
// Iterate hits array
for (int i = 0 ; i < c1.length(); i++) {
    JSONObject jObject = c1.getJSONObject(i);
    System.out.println(jObject.get("_source"));
}

Resultant data looks like,

{"Name":"ABC_123","Status":"false","Date":"2010-08-16T11:07:48","ID":"123"}
{"Name":"ABC_678","Status":"false","Date":"2010-08-16T12:00:12","ID":"124"}
{"Name":"FGH_122","Status":"true","Date":"2010-08-16T12:01:48","ID":"125"}
{"Name":"TYT_333","Status":"false","Date":"2010-08-16T12:06:48","ID":"126"}
{"Name":"CVF_230","Status":"false","Date":"2010-08-16T12:07:18","ID":"127"}
{"Name":"AWE_101","Status":"true","Date":"2010-08-16T12:03:48","ID":"128"}
{"Name":"WEC_299","Status":"true","Date":"2010-08-16T12:07:29","ID":"129"}

As well checkout Demo , It's a client side iteration. If you can able to do it in client side this may help you.