7

I am trying to parse JSON using a Notes agent, JSON is fetched using Apache HttpClient.

Here is the code that return the JSON

import lotus.domino.*;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;

      Session session = getSession();
      AgentContext agentContext = session.getAgentContext();

      HttpClient client = HttpClientBuilder.create().build();
      HttpGet request = new HttpGet("http://api.acme.com/customer");
      request.addHeader("accept", "application/json");
      request.addHeader("Host", "api.acme.com");
      request.addHeader("X-Api-Version", "1.0");
      request.addHeader("Authorization", "Basic ...");

      HttpResponse response = client.execute(request);       

The JSON Looks like this.

[ 
  { 
    "id": 123456, 
    "insertDate": "2014-05-12T16:51:38.343", 
    "read": false, 
    "site": "acme.com", 
    "Email": "john.doe@acme.com", 
    "location": "/customer/1212?v=1.0" 
  } 
] 

I have tried to use JSONObject and JSONArray from JSON.org but could not get it to work I need some example code from the json.org package or other ways to parse the json.

Tristan
  • 1,069
  • 11
  • 16
Thomas Adrian
  • 3,331
  • 5
  • 28
  • 56
  • When you parse the JSON and `toString` the result it should look pretty much exactly like the incoming JSON. What do you get when you parse? (And have you gone to json.org and studied the JSON syntax? It only takes 5-10 minutes to learn.) – Hot Licks May 19 '14 at 17:09
  • @Thomas: Your solution would be perfect for me. Which version of the apache http client do you use? I am working with a domino server 9. – Georg Kastenhofer Jun 04 '18 at 15:40

1 Answers1

17

You can get the JSON from the Entity in the HttpResponse using HttpResponse#getEntity. Once you have that, then just create a new JSONArray and iterate the array to access the values in your JSON object:

String json = IOUtils.toString(response.getEntity().getContent());
JSONArray array = new JSONArray(json);
for (int i = 0; i < array.length(); i++) {
    JSONObject object = array.getJSONObject(i);
    log.info("the id is {}", object.getInt("id"));
    log.info("the insertDate is {}", object.getString("insertDate"));
    log.info("read is {}", object.getBoolean("read"));
    log.info("the site is {}", object.getString("site"));
    log.info("the Email is {}", object.getString("Email"));
    log.info("the location is {}", object.getString("location"));
}

I saved the JSON in a JSONBlob at http://jsonblob.com/537a43bfe4b047fa2ef5f15d and created a unit test that requests that JSON:

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.IOUtils;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.JSONArray;
import org.json.JSONObject;
import org.junit.Test;

@Slf4j
public class JsonTest {
    @Test
    public void test() throws Exception {
        HttpClient client = HttpClientBuilder.create().build();
        HttpGet request = new HttpGet("http://jsonblob.com/api/jsonBlob/537a43bfe4b047fa2ef5f15d");
        request.addHeader("accept", "application/json");
        HttpResponse response = client.execute(request);
        String json = IOUtils.toString(response.getEntity().getContent());
        JSONArray array = new JSONArray(json);
        for (int i = 0; i < array.length(); i++) {
            JSONObject object = array.getJSONObject(i);
            log.info("the id is {}", object.getInt("id"));
            log.info("the insertDate is {}", object.getString("insertDate"));
            log.info("read is {}", object.getBoolean("read"));
            log.info("the site is {}", object.getString("site"));
            log.info("the Email is {}", object.getString("Email"));
            log.info("the location is {}", object.getString("location"));
        }
    }
}

And the output from running it is:

11:23:19.508 [main] INFO  JsonTest - the id is 123456
11:23:19.516 [main] INFO  JsonTest - the insertDate is 2014-05-12T16:51:38.343
11:23:19.516 [main] INFO  JsonTest - read is false
11:23:19.516 [main] INFO  JsonTest - the site is acme.com
11:23:19.516 [main] INFO  JsonTest - the Email is john.doe@acme.com
11:23:19.516 [main] INFO  JsonTest - the location is /customer/1212?v=1.0

I used the IOUtils class to convert the InputStream from the HttpResponse Entity, but this can be done anyway you like (and converting it like I did may not be the best idea depending on how big the JSON is).

Tristan
  • 1,069
  • 11
  • 16
  • You should _never_ just decode bytes into strings without respecting the encoding. Use (https://hc.apache.org/httpcomponents-core-ga/httpcore/apidocs/org/apache/http/util/EntityUtils.html#toString(org.apache.http.HttpEntity) – AbuNassar Aug 24 '16 at 19:30