How to add parameters to HttpURLConnection using POST using NameValuePair

Michal picture Michal · Mar 19, 2012 · Viewed 441.7k times · Source

I am trying to do POST with HttpURLConnection(I need to use it this way, can't use HttpPost) and I'd like to add parameters to that connection such as

post.setEntity(new UrlEncodedFormEntity(nvp));

where

nvp = new ArrayList<NameValuePair>();

having some data stored in. I can't find a way how to add this ArrayList to my HttpURLConnection which is here:

HttpsURLConnection https = (HttpsURLConnection) url.openConnection();
https.setHostnameVerifier(DO_NOT_VERIFY);
http = https;
http.setRequestMethod("POST");
http.setDoInput(true);
http.setDoOutput(true);

The reason for that awkward https and http combination is the need for not verifying the certificate. That is not a problem, though, it posts the server well. But I need it to post with arguments.

Any ideas?


Duplicate Disclaimer:

Back in 2012, I had no idea how parameters were inserted into an HTTP POST request. I was hanging on to NameValuePair because it was in a tutorial. This question might seem like a duplicate, however, my 2012 self read that other question and it was NOT using NameValuePair. It did not, in fact, solve my problem.

Answer

tomusiaka picture tomusiaka · Nov 21, 2012

You can get output stream for the connection and write the parameter query string to it.

URL url = new URL("http://yoururl.com");
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);

List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("firstParam", paramValue1));
params.add(new BasicNameValuePair("secondParam", paramValue2));
params.add(new BasicNameValuePair("thirdParam", paramValue3));

OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(
        new OutputStreamWriter(os, "UTF-8"));
writer.write(getQuery(params));
writer.flush();
writer.close();
os.close();

conn.connect();

...

private String getQuery(List<NameValuePair> params) throws UnsupportedEncodingException
{
    StringBuilder result = new StringBuilder();
    boolean first = true;

    for (NameValuePair pair : params)
    {
        if (first)
            first = false;
        else
            result.append("&");

        result.append(URLEncoder.encode(pair.getName(), "UTF-8"));
        result.append("=");
        result.append(URLEncoder.encode(pair.getValue(), "UTF-8"));
    }

    return result.toString();
}