How To Use Recording Add-ons in Java

{
  "status":"successful",
  "message":null,
  "code":null,
  "results":{
    "ibm_watson_speechtotext":{
      "request_sid":"XRc82d4197bbc51d5982588ae367365a51",
      "status":"successful",
      "message":null,
      "code":null,
      "payload":[
        {
        "content_type":"application/json",
        "url":"https://api.twilio.com/2010-04-01/Accounts/AC597d02bf69de79f8f411f289ac211a0d/Recordings/REab85c1c2860471abf040b545c4e5aa40/AddOnResults/XRc82d4197bbc51d5982588ae367365a51/Payloads/XH364bd4514b1377fd8844cd9793416131/Data"
        }
      ],
      "links":{
        "add_on_result":"https://api.twilio.com/2010-04-01/Accounts/AC597d02bf69de79f8f411f289ac211a0d/Recordings/REab85c1c2860471abf040b545c4e5aa40/AddOnResults/XRc82d4197bbc51d5982588ae367365a51",
        "payloads":"https://api.twilio.com/2010-04-01/Accounts/AC597d02bf69de79f8f411f289ac211a0d/Recordings/REab85c1c2860471abf040b545c4e5aa40/AddOnResults/XRc82d4197bbc51d5982588ae367365a51/Payloads",
        "recording":"https://api.twilio.com/2010-04-01/Accounts/AC597d02bf69de79f8f411f289ac211a0d/Recordings/REab85c1c2860471abf040b545c4e5aa40"
      }
    }
  }
}

{
  "user_token": "XRf951c9b0bce23930750991099e553b0a",
  "results":[
    {
      "results":[
        {
          "keywords_result":{},
          "alternatives":[
            {
            "timestamps":[
              ["I", 0.04, 0.28],
              ["love", 0.28, 0.71],
              ["coding", 0.74, 1.25]
            ],
            "confidence":0.782,
            "transcript":"I love coding "
            }
          ],
          "final":true
        }
      ],
      "result_index":0
    }
  ],
  "id":"b0e7a660-bcb6-11e6-8b1b-192a5f5dc12f",
  "event":"recognitions.completed_with_results"
}

import com.jayway.jsonpath.DocumentContext;
import com.jayway.jsonpath.JsonPath;
import com.jayway.jsonpath.ReadContext;
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;
import com.mashape.unirest.http.exceptions.UnirestException;
import com.twilio.twiml.*;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import java.util.List;
import java.util.Map;

public class RecordingController {

    private static final String ACCOUNT_SID = System.getenv("TWILIO_ACCOUNT_SID");
    private static final String AUTH_TOKEN = System.getenv("TWILIO_AUTH_TOKEN");

    @RequestMapping(value = "/voice",
            produces = "application/xml",
            method = {RequestMethod.GET, RequestMethod.POST})
    public ResponseEntity<String> voice() throws TwiMLException {
        // Start our TwiML response
        VoiceResponse voiceResponse = new VoiceResponse.Builder()
                .say(new Say
                        .Builder("Hi! I want to know what do you think about coding.")
                        .build())
                .record(new Record.Builder().maxLength(10).action("/recording").build())
                .hangup(new Hangup())
                .build();

        return okResponse(voiceResponse);
    }

    @RequestMapping(value = "/recording",
            produces = "application/xml",
            method = {RequestMethod.GET, RequestMethod.POST})
    public ResponseEntity<String> recording(@RequestParam("RecordingUrl") String recordingUrl) throws TwiMLException {
        System.out.println(recordingUrl);

        // Start our TwiML response
        VoiceResponse voiceResponse = new VoiceResponse.Builder()
                .say(new Say
                        .Builder("Thanks for howling... take a listen to what you howled.")
                        .build())
                .play(new Play.Builder(recordingUrl).build())
                .say(new Say.Builder("Goodbye.").build())
                .build();

        return okResponse(voiceResponse);
    }
    @RequestMapping(value = "/recording",
            produces = "application/xml",
            consumes = "application/json",
            method = {RequestMethod.POST, RequestMethod.PUT})
    public ResponseEntity<String> callback(@RequestParam("AddOns") String addOns) throws UnirestException {
        // If the Watson Speech to Text add-on found nothing, return immediately
        ReadContext addonsContext = JsonPath.parse(addOns);
        Map<String, Object> results = addonsContext.read("$.results");
        if(!results.containsKey("ibm_watson_speechtotext")) {
            return new ResponseEntity<>(
                    "Add Watson Speech to Text add-on in your Twilio console", HttpStatus.OK);
        }

        // Retrieve the Watson Speech to Text add-on results
        String payloadUrl = addonsContext.read("$.results['ibm_watson_speechtotext'].payload[0].url");
        HttpResponse<String> response = Unirest
                .get(payloadUrl)
                .basicAuth(ACCOUNT_SID, AUTH_TOKEN)
                .asString();

        DocumentContext speechToTextContext = JsonPath.parse(response.getBody());
        List<String> transcripts = speechToTextContext
                .read("$.results[0].results[*].alternatives[0].transcript");

        return new ResponseEntity<>(String.join("", transcripts), HttpStatus.OK);
    }

    private ResponseEntity<String> okResponse(VoiceResponse voiceResponse) throws TwiMLException {
        return new ResponseEntity<>(voiceResponse.toXml(), getHttpHeaders(), HttpStatus.OK);
    }

    private HttpHeaders getHttpHeaders() {
        final HttpHeaders httpHeaders = new HttpHeaders();
        httpHeaders.setContentType(MediaType.APPLICATION_XML);
        return httpHeaders;
    }
}