Java: how to use UrlConnection to post request with authorization?
Solution 1
A fine example found here. Powerlord got it right, below, for POST you need HttpURLConnection
, instead.
Below is the code to do that,
URL url = new URL(urlString);
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
conn.setRequestProperty ("Authorization", encodedCredentials);
OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());
writer.write(data);
writer.flush();
String line;
BufferedReader reader = new BufferedReader(new
InputStreamReader(conn.getInputStream()));
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
writer.close();
reader.close();
Change URLConnection
to HttpURLConnection
, to make it POST request.
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
Suggestion (...in comments):
You might need to set these properties too,
conn.setRequestProperty( "Content-type", "application/x-www-form-urlencoded");
conn.setRequestProperty( "Accept", "*/*" );
Solution 2
I don't see anywhere in the code where you specify that this is a POST request. Then again, you need a java.net.HttpURLConnection
to do that.
In fact, I highly recommend using HttpURLConnection
instead of URLConnection
, with conn.setRequestMethod("POST");
and see if it still gives you problems.
Solution 3
To do oAuth authentication to external app (INSTAGRAM) Step 3 "get the token after receiving the code" Only code below worked for me
Worth to state also that it worked for me using some localhost URL with a callback servlet configured with name "callback in web.xml and callback URL registered: e.g. localhost:8084/MyAPP/docs/insta/callback
BUT after successfully completed authentication steps, using same external site "INSTAGRAM" to do GET of Tags or MEDIA to retrieve JSON data using initial method didn't work. Inside my servlet to do GET using url like e.g. api.instagram.com/v1/tags/MYTAG/media/recent?access_token=MY_TOKEN only method found HERE worked
Thanks to all contributors
URL url = new URL(httpurl);
HashMap<String, String> params = new HashMap<String, String>();
params.put("client_id", id);
params.put("client_secret", secret);
params.put("grant_type", "authorization_code");
params.put("redirect_uri", redirect);
params.put("code", code); // your INSTAGRAM code received
Set set = params.entrySet();
Iterator i = set.iterator();
StringBuilder postData = new StringBuilder();
for (Map.Entry<String, String> param : params.entrySet()) {
if (postData.length() != 0) {
postData.append('&');
}
postData.append(URLEncoder.encode(param.getKey(), "UTF-8"));
postData.append('=');
postData.append(URLEncoder.encode(String.valueOf(param.getValue()), "UTF-8"));
}
byte[] postDataBytes = postData.toString().getBytes("UTF-8");
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
conn.setRequestProperty("Content-Length", String.valueOf(postDataBytes.length));
conn.setDoOutput(true);
conn.getOutputStream().write(postDataBytes);
BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
StringBuilder builder = new StringBuilder();
for (String line = null; (line = reader.readLine()) != null;) {
builder.append(line).append("\n");
}
reader.close();
conn.disconnect();
System.out.println("INSTAGRAM token returned: "+builder.toString());
Solution 4
To send a POST request call:
connection.setDoOutput(true); // Triggers POST.
If you want to sent text in the request use:
java.io.OutputStreamWriter wr = new java.io.OutputStreamWriter(connection.getOutputStream());
wr.write(textToSend);
wr.flush();
Solution 5
On API 22 The Use Of BasicNamevalue Pair is depricated, instead use the HASMAP for that. To know more about the HasMap visit here more on hasmap developer.android
package com.yubraj.sample.datamanager;
import android.content.Context;
import android.os.AsyncTask;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import com.yubaraj.sample.utilities.GeneralUtilities;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Map;
import javax.net.ssl.HttpsURLConnection;
/**
* Created by yubraj on 7/30/15.
*/
public class ServerRequestHandler {
private static final String TAG = "Server Request";
OnServerRequestComplete listener;
public ServerRequestHandler (){
}
public void doServerRequest(HashMap<String, String> parameters, String url, int requestType, OnServerRequestComplete listener){
debug("ServerRequest", "server request called, url = " + url);
if(listener != null){
this.listener = listener;
}
try {
new BackgroundDataSync(getPostDataString(parameters), url, requestType).execute();
debug(TAG , " asnyc task called");
} catch (Exception e) {
e.printStackTrace();
}
}
public void doServerRequest(HashMap<String, String> parameters, String url, int requestType){
doServerRequest(parameters, url, requestType, null);
}
public interface OnServerRequestComplete{
void onSucess(Bundle bundle);
void onFailed(int status_code, String mesage, String url);
}
public void setOnServerRequestCompleteListener(OnServerRequestComplete listener){
this.listener = listener;
}
private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException {
StringBuilder result = new StringBuilder();
boolean first = true;
for(Map.Entry<String, String> entry : params.entrySet()){
if (first)
first = false;
else
result.append("&");
result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
result.append("=");
result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
}
return result.toString();
}
class BackgroundDataSync extends AsyncTask<String, Void , String>{
String params;
String mUrl;
int request_type;
public BackgroundDataSync(String params, String url, int request_type){
this.mUrl = url;
this.params = params;
this.request_type = request_type;
}
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... urls) {
debug(TAG, "in Background, urls = " + urls.length);
HttpURLConnection connection;
debug(TAG, "in Background, url = " + mUrl);
String response = "";
switch (request_type) {
case 1:
try {
connection = iniitializeHTTPConnection(mUrl, "POST");
OutputStream os = connection.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(params);
writer.flush();
writer.close();
os.close();
int responseCode = connection.getResponseCode();
if (responseCode == HttpsURLConnection.HTTP_OK) {
/* String line;
BufferedReader br=new BufferedReader(new InputStreamReader(connection.getInputStream()));
while ((line=br.readLine()) != null) {
response+=line;
}*/
response = getDataFromInputStream(new InputStreamReader(connection.getInputStream()));
} else {
response = "";
}
} catch (IOException e) {
e.printStackTrace();
}
break;
case 0:
connection = iniitializeHTTPConnection(mUrl, "GET");
try {
if (connection.getResponseCode() == connection.HTTP_OK) {
response = getDataFromInputStream(new InputStreamReader(connection.getInputStream()));
}
} catch (Exception e) {
e.printStackTrace();
response = "";
}
break;
}
return response;
}
@Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
if(TextUtils.isEmpty(s) || s.length() == 0){
listener.onFailed(DbConstants.NOT_FOUND, "Data not found", mUrl);
}
else{
Bundle bundle = new Bundle();
bundle.putInt(DbConstants.STATUS_CODE, DbConstants.HTTP_OK);
bundle.putString(DbConstants.RESPONSE, s);
bundle.putString(DbConstants.URL, mUrl);
listener.onSucess(bundle);
}
//System.out.println("Data Obtained = " + s);
}
private HttpURLConnection iniitializeHTTPConnection(String url, String requestType) {
try {
debug("ServerRequest", "url = " + url + "requestType = " + requestType);
URL link = new URL(url);
HttpURLConnection conn = (HttpURLConnection) link.openConnection();
conn.setRequestMethod(requestType);
conn.setDoInput(true);
conn.setDoOutput(true);
return conn;
}
catch(Exception e){
e.printStackTrace();
}
return null;
}
}
private String getDataFromInputStream(InputStreamReader reader){
String line;
String response = "";
try {
BufferedReader br = new BufferedReader(reader);
while ((line = br.readLine()) != null) {
response += line;
debug("ServerRequest", "response length = " + response.length());
}
}
catch (Exception e){
e.printStackTrace();
}
return response;
}
private void debug(String tag, String string) {
Log.d(tag, string);
}
}
and Just call the function when you needed to get the data from server either by post or get like this
HashMap<String, String>params = new HashMap<String, String>();
params.put("action", "request_sample");
params.put("name", uname);
params.put("message", umsg);
params.put("email", getEmailofUser());
params.put("type", "bio");
dq.doServerRequest(params, "your_url", DbConstants.METHOD_POST);
dq.setOnServerRequestCompleteListener(new ServerRequestHandler.OnServerRequestComplete() {
@Override
public void onSucess(Bundle bundle) {
debug("data", bundle.getString(DbConstants.RESPONSE));
}
@Override
public void onFailed(int status_code, String mesage, String url) {
debug("sample", mesage);
}
});
Now it is complete.Enjoy!!! Comment it if find any problem.
Niko Gamulin
Engineer/Researcher, working in the field of Machine Learning.
Updated on September 21, 2020Comments
-
Niko Gamulin over 3 years
I would like to generate POST request to a server which requires authentication. I tried to use the following method:
private synchronized String CreateNewProductPOST (String urlString, String encodedString, String title, String content, Double price, String tags) { String data = "product[title]=" + URLEncoder.encode(title) + "&product[content]=" + URLEncoder.encode(content) + "&product[price]=" + URLEncoder.encode(price.toString()) + "&tags=" + tags; try { URL url = new URL(urlString); URLConnection conn; conn = url.openConnection(); conn.setRequestProperty ("Authorization", "Basic " + encodedString); conn.setDoOutput(true); conn.setDoInput(true); OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream()); wr.write(data); wr.flush(); // Get the response BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream())); String line; while ((line = rd.readLine()) != null) { // Process line... } wr.close(); rd.close(); return rd.toString(); } catch (MalformedURLException e) { e.printStackTrace(); return e.getMessage(); } catch (IOException e) { e.printStackTrace(); return e.getMessage(); } }
but the server doesn't receive the authorization data. The line which is supposed to add authorization data is the following:
conn.setRequestProperty ("Authorization", "Basic " + encodedString);
and the line
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
also throws an IOException.
Anyway I would be very thankful if anyone could suggest any fix of the logic above in order to enable authorization using POST with UrlConnection.
but obviously it doesn't work as it is supposed to although if the same logic is used for GET request everything works fine.
-
Niko Gamulin over 14 yearsThis is GET request which is not a problem.
-
Adeel Ansari over 14 yearsNot a big difference in terms of authorization.
-
Powerlord over 14 yearsNifty, I never knew about this class. However, this class is abstract, so he'd actually need an implementing class for it.
-
jarnbjo over 14 yearsSure, you need to implement an application specific way to get the credentials. In an interactive application, you may e.g. need a popup dialog.
-
David Newcomb over 11 yearsIt is if you came here looking for how to do the post bit :(
-
Bob about 10 yearsThis is the correct answer. You can not make a post request with URLConnection. You must use HttpURLConnection.
-
Bob about 10 yearsThis answer is not correct: This Answer is: stackoverflow.com/a/2165000/787202
-
Adeel Ansari almost 10 years@Stallman: Same as what it means in the original question. You'll find
encodedString
instead ofencodedCredential
, which means password, simply. -
Ray Kiddy over 8 yearsThe bit above did not work when I tried it. I had to add set the following on the connection: uc.setRequestProperty( "Content-type", "application/x-www-form-urlencoded" ); uc.setRequestProperty( "Accept", "*/*" );
-
Yousha Aleayoub about 8 years
setDoOutput(true)
forcesUrlConnection
to POST... right? -
Adeel Ansari almost 8 years@YoushaAleayoub: Nope.
-
Yousha Aleayoub almost 8 years@AdeelAnsari, No? so what is this: stackoverflow.com/questions/8587913/…
-
Adeel Ansari almost 8 years@YoushaAleayoub, It's just stating that it's used to request body, which is usually the case with POST -- and PUT, not just POST. So, we can't say it forces to POST, that's what it does in practice though; but taking it for granted would be wrong. The right thing to use is
httpUrlConn.setRequestMethod("POST")
. -
Yousha Aleayoub almost 8 years@AdeelAnsari, good point and thanks for reply... but what if we use
URLConnection
, notHTTPURLConnection
? -
Adeel Ansari almost 8 years@YoushaAleayoub, Why stick with
URLConnection
, when you really want to POST. Beware, HEAD, GET, POST, PUT etc., all are HTTP's methods, or might also be of some other protocol; but general URL doesn't care. -
Würgspaß almost 6 yearsnope.
connection.setDoOutput(true);
does not trigger POST. Add this lineSystem.out.println(((HttpURLConnection)connection).getRequestMethod());
and you will readGET
.