How to decode JSON from Java REST API request?

Question

I'm sending data to an API from Java using POST.

What I'm trying to do is send a particular variable to the API in the POST request, and then use the value of it. But currently the value is empty. The API is definitely being called.

My Java looks like this:

String line;
StringBuffer jsonString = new StringBuffer();

try {
    URL url = new URL("https://www.x.com/api.php");
    String payload = "{\"variable1\":\"value1\",\"variable2\":\"value2\"}";

    HttpURLConnection connection = (HttpURLConnection) url.openConnection();

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

    BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
    while ((line = br.readLine()) != null) {
        jsonString.append(line);
    }
    br.close();
    connection.disconnect();
}

This is based on: How to send Request payload to REST API in java?

Currently the value isn't being read correctly. Am I sending it correctly in Java? Do I have to do something to decode it?

pgiecek · Answer 1 · 2014-10-01T20:16:57.210

1

The $_POST variable is not set for all HTTP POST requests, but only for specific types, e.g application/x-www-form-urlencoded.

Since you are posting a request containing JSON entity (application/json), you need to access it as follows.

$json = file_get_contents('php://input');
$entity= json_decode($json, TRUE);

edited Oct 01 '14 at 20:16

answered Oct 01 '14 at 20:09

pgiecek

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damn it you were faster xD take my medal! – Andreas Oct 01 '14 at 20:14
Look at `json_decode()` [documentation](http://php.net/manual/en/function.json-decode.php). The second parameter determines whether to return associative array. This should work `$entity['variable1']`. – pgiecek Oct 01 '14 at 22:42

score 0 · Answer 2 · answered Oct 01 '14 at 20:07

You can try to use the following code instead of your String variable payload:

List<NameValuePair> payload = new ArrayList<NameValuePair>();

payload.add(new BasicNameValuePair("variable1", "value1");

That worked for me

How to decode JSON from Java REST API request?

2 Answers2