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How to fix "Connection Reset" in Eclipse for HTTPS url

I am trying to parse a https url link and getting a connection reset problem in eclipse , however it works in eclipse ( returns 301 response code though )
How to solve this ?
Thanks
try {
String url = "http://api.demo.globalgatewaye4.firstdata.com/transaction/search?start_date=2018-01-07&end_date=2018-01-09";
URL obj = new URL(url);
HttpURLConnection conn = (HttpURLConnection) obj.openConnection();
conn.setReadTimeout(5000);
conn.addRequestProperty("Authorization", "Basic *****************");
System.out.println("Request URL ... " + url);
boolean redirect = false;
// normally, 3xx is redirect
int status = conn.getResponseCode();
if (status != HttpURLConnection.HTTP_OK) {
if (status == HttpURLConnection.HTTP_MOVED_TEMP
|| status == HttpURLConnection.HTTP_MOVED_PERM
|| status == HttpURLConnection.HTTP_SEE_OTHER)
redirect = true;
}
System.out.println("Response Code ... " + status);
if (redirect) {
// get redirect url from "location" header field
String newUrl = conn.getHeaderField("Location");
// get the cookie if need, for login
String cookies = conn.getHeaderField("Set-Cookie");
// open the new connnection again
conn = (HttpURLConnection) new URL(newUrl).openConnection();
conn.setRequestProperty("Cookie", cookies);
conn.addRequestProperty("Accept-Language", "en-US,en;q=0.8");
conn.addRequestProperty("User-Agent", "Mozilla");
conn.addRequestProperty("Referer", "google.com");
System.out.println("Redirect to URL : " + newUrl);
}
BufferedReader in = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
String inputLine;
StringBuffer html = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
html.append(inputLine);
}
in.close();
System.out.println("URL Content... \n" + html.toString());
System.out.println("Done");
} catch (Exception e) {
e.printStackTrace();
}
This returns a HTTP response code "301" which redirects it to a HTTPS url which in turn give s a connection reset error .
How to solve this error in eclipse , or is there a generic way .

Thank you . Found the solution . problem was related to TLS not being available in the java version i was using .
Had to switch to a higher java version .

Send JSON data through POST in Java

I have this code to send JSON data (passed as a string) to the server (This code works when English characters are to be sent as values in dataJSON as far as I tested):
private static String sendPost(String url, String dataJSON) throws Exception {
System.out.println("Data to send: " + dataJSON);
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
String type = "application/json;charset=utf-8";
// add reuqest header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", "Mozilla/5.0");
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
con.setRequestProperty("Content-Length", String.valueOf(dataJSON.getBytes("UTF-8").length));
con.setRequestProperty("Content-Type", type);
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeUTF(dataJSON);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
System.out.println("Response Code : " + responseCode);
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.print("Response string from POST: " + response.toString() + "\n");
return response.toString();
}
Problem is I don't get correct response, which I get for example using DHC Restlet Client.
The problem is I think the dataJSON must be encoded in UTF8. That's how the server expects it most likely.
But it seems I have some problem in code the way I try to convert it and send it.
Can someone help me send data in body as UTF8 string in above example?

I think I solved with this approach:
private static String sendPost2(String urlStr, String dataJSON) throws Exception {
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5000);
conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setRequestMethod("POST");
OutputStream os = conn.getOutputStream();
os.write(dataJSON.getBytes("UTF-8"));
os.close();
// read the response
InputStream in = new BufferedInputStream(conn.getInputStream());
String result = new BufferedReader(new InputStreamReader(in)) .lines().collect(Collectors.joining("\n"));
in.close();
conn.disconnect();
return result;
}
Please suggest alternative if you see problem with it.

Access website through vpnbook.com

I am working on application to access a web page through vpnbook.com.
My code is sending post request to URL "https://webproxy.vpnbook.com/includes/process.php?action=update" with post body as "u=yahoo.com&webproxylocation=random"
i am getting response code 302. and HTTP response header contains location
"Location=[http://www.vpnbook.com/webproxy]"
But same request was getting correct correct result when opening through web browser.
result contains header response
"Location:https://usproxy.vpnbook.com/browse.phpu=DWnjEwVwhlG5GQhW&b=0&f=norefer"
please tell me what is going wrong in my code.
try{
URL url = new URL("https://webproxy.vpnbook.com/includes/process.php?action=update");
HttpsURLConnection c = (HttpsURLConnection) url.openConnection();
c.setRequestProperty("User-Agent", USER_AGENT);
c.setRequestProperty("Accept-Language", ACCEPT_LANG);
c.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
c.setRequestProperty("Host", "webproxy.vpnbook.com");
c.setRequestProperty("Origin", "http://www.vpnbook.com");
c.setRequestProperty("Referer", "http://www.vpnbook.com/webproxy");
c.setRequestMethod("POST");
c.setDoInput(true);
c.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(c.getOutputStream());
wr.writeBytes("u=yahoo.com&webproxylocation=random");
wr.flush();
wr.close();
int responseCode = c.getResponseCode();
System.out.println("\nSending 'GET' request to URL : " + url);
System.out.println("Response Code : " + responseCode);
System.out.println("Response headers : " + c.getHeaderFields());
Map<String, List<String>> resHdr = c.getHeaderFields();
if( resHdr.containsKey("Set-Cookie") ){
cookies=resHdr.get("Set-Cookie").toString();
cookies = cookies.replaceAll("\\[|\\]", "");
System.out.println(cookies);
}
BufferedReader in =
new BufferedReader(new InputStreamReader(c.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.println(response);
}catch(Exception ex) { ex.printStackTrace(); }

In HttpURLConnection Why don't JSONObject as Params work but String as Params are working

I am using HttpUrlConnection to post some data to my server here is the function:
private String register(String myurl) throws IOException {
String resp = null;
try {
JSONObject parameters = new JSONObject();
// parameters.put("jsonArray", ((makeJSON())));
parameters.put("key", "key");//getencryptkey());
URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
// conn.setReadTimeout(10000 /* milliseconds *///);
// conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestProperty("Content-Type", "application/json");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setRequestMethod("POST");
OutputStream out = new BufferedOutputStream(conn.getOutputStream());
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out, "UTF-8"));
writer.write(parameters.toString());
writer.close();
out.close();
int responseCode = conn.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
System.out.println("Response Code : " + responseCode);
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.println("strngbuffr" + response.toString());
resp = response.toString();
} catch (Exception exception) {
System.out.println("Exception: " + exception);
}
System.out.println("rsp"+ resp.toString());
return resp.toString();
}
I get the response code as 200, which means connection is okay however I get empty variables on PHP side, what can be wrong here?
Earlier I was sending a JSON array too but just to test functonality I commented that out now I am only sending one variable key as "key"
Its amazing to see, this sample code works - sans the JSON array and the key value pairs:
private String sendPost(String url) throws Exception {
String USER_AGENT = "Mozilla/5.0";
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
//add reuqest header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
String urlParameters ="sn=C02G8416DRJM&cn=&locale=&caller=&num=12345";
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
System.out.println("Post parameters : " + urlParameters);
System.out.println("Response Code : " + responseCode);
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
System.out.println("rvsp"+response.toString());
return response.toString();
}
So it boils down to replacing this:
JSONObject parameters = new JSONObject();
parameters.put("jsonArray", new JSONArray(Arrays.asList(makeJSON())));
parameters.put("key", getencryptkey());
by this:
String urlParameters ="jArr="+makeJSON()+"Key="+getencryptkey();
and I am still curious.

I reckon the problem here is not at the Java side, If the parameters is of fixed type like in json in your case, the JSON Object as POST params method will work if collected this way on the php side:
<?php
$json = file_get_contents('php://input');
$obj = json_decode($json);
print_r($obj);
print_r("this is a test response");
?>

The problem here was not with the Java side, it was with the php side, the JSON Object as POST params method will work if collected this way on the php side:
<?php
$json = file_get_contents('php://input');
$obj = json_decode($json);
print_r($obj);
print_r("this is a test");
?>

How to set parameters in a GET request in Java

So I want to send a GET request with parameters. But it only seems to have conventions for the url you send the request to. Unlike the POST request, I see no way to pass parameters in it.
How I send the GET request now, without parameters (might be wrong):
String url = "http://api.netatmo.net/api/getuser";
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
// optional default is GET
con.setRequestMethod("GET");
//add request header
con.setRequestProperty("User-Agent", USER_AGENT);
int responseCode = con.getResponseCode();
Log.v(TAG, ("\nSending 'GET' request to URL : " + url));
Log.v(TAG, ("Response Code : " + responseCode));
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
Log.v(TAG, (response.toString()));
How I send the POST request with parameters:
String url = "https://api.netatmo.net/oauth2/token";
URL obj = new URL(url);
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();
//add request header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
String urlParameters = "grant_type=password&client_id=myid&client_secret=mysecret&username=myusername&password=mypass";
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
Log.v(TAG, "\nSending 'POST' request to URL : " + url);
Log.v(TAG, "Post parameters : " + urlParameters);
Log.v(TAG, "Response Code : " + responseCode);
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
Log.v(TAG, response.toString());
access_token = response.substring(17, 74);
refresh_token = response.substring(93,150);
getRequest = "/api/getuser?access_token=" + access_token + " HTTP/1.1";
Log.v(TAG, access_token);
Log.v(TAG, refresh_token);
Log.v(TAG, getRequest);

As per the HTTP specification GET supports only path params or url params and hence you cannot put the params in HTTP request body as you do in POST request.
As Sotirios mentioned in the comments, technically you can still push params in the GET body, but if the APIs are respecting the specs, they will not provide you a way to do it.

Have you tried to add the query params to the request java.net.URL?
String url = "http://api.netatmo.net/api/getuser?access_token=" + access_token;
URL obj = new URL(url);

I was encountering the same problem, trying this:
String bla = "http://api.netatmo.net/api/devicelist?access_token=" + AUTH_TOKEN;
URL url = new URL(bla);
BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream()));
String line = "";
String message = "";
while ((line = reader.readLine()) != null)
{
message += line;
}
I got an exception that the syntax was not correct. When I changed the syntax (by for example encoding with UTF 8) the API would just return errors (like 404 not found...).
I finally got it working using this:
try
{
System.out.println("Access Token: " + AUTH_TOKEN);
String url = "http://api.netatmo.net/api/devicelist";
String query = "access_token=" + URLEncoder.encode(AUTH_TOKEN, CHARSET);
URLConnection connection = new URL(url + "?" + query).openConnection();
connection.setRequestProperty("Accept-Charset", CHARSET);
InputStream response = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(response));
String line = "";
String message = "";
while ((line = reader.readLine()) != null)
{
message += line;
}
return message;
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Note: CHARSET = "UTF-8"

Turns out the url the API provided confused me greatly. I fixed the url and it works now.