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Java HTTP connection seems to remain open

I have created a connection in Java to private API
String urlRequest = "https://localhost:8080/orders/create";
String username = "test";
String password = "test";
String certificatePass = "test";
byte[] authEncBytes = Base64.getEncoder().encode((username + ":" + password).getBytes());
URL url = new URL(urlRequest);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Authorization", "Basic " + new String(authEncBytes));
conn.setRequestProperty("Content-Type", "application/json");
conn.setRequestProperty("Accept", "application/json");
conn.setDoOutput(true);
conn.setDoInput(true);
InputStream is = conn.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
is.close();
After the initial pass, connection seems to remain open, because when running the code from the start, HttpURLConnection throws an Exception at conn.setRequestMethod("POST");,
"Can't reset method: already connected"
I managed to somehow close it now, I don't know what have I done, but does anyone know what the issue here could have been? I restarted my PC in the meantime, and it would still thrown an exception at conn.setRequestMethod("POST");, I don't understand how can a connection persist between restarts. I also tried adding conn.disconnect() before trying to set request method, and that didn't seem to work either. The only thing that made a difference was changing the URL, but I could only connect once, every next time running the code would give me the same exception.
How do I close the connection properly?

Had the issue again today and the problem was with expressions in debug mode. I was calling connect there, I guess while testing so in case anyone didn't know, expressions do affect your variables and can change what's in memory. For instance, having:
int a = 5;
System.out.println(a);
in your code and having a = 6 in your Expressions list, System.out.println(a) will print 6, not 5.
Deleting expressions fixed my problem.

I think your question already has an answer here.
Closing URLConnection and InputStream correctly?
Close your connection at end of the code and don't do it before setRequest method.

Java: HTTPS URL not redirecting

I'm trying to get a redirected URL from newURLConnection, but when I print out, it still outputs what the URL is before it is redirected. I'm certain that the original newURLConnection is a legitimate URL because when I enter it into a web browser it redirects automatically. I've tried it with conn.setInstanceFollowRedirects set to both false and true, and neither works...for some reason it's just impossible for me to get the redirected URL. Help would definitely be appreciated.
//open a connection
URLConnection newURLConnection = params[0].openConnection();
HttpURLConnection conn = (HttpURLConnection) newURLConnection;
//following code sourced from mkyong.com
conn.setInstanceFollowRedirects(true);
//HttpURLConnection.setFollowRedirects(true);
conn.connect();
//get the redirected URL
InputStream newURLConnectedStream = conn.getInputStream();
System.out.println("" + conn.getURL());

Try the following code to get it,
URL url = new URL(url);
HttpURLConnection ucon = (HttpURLConnection) url.openConnection();
ucon.setInstanceFollowRedirects(false);
URL secondURL = new URL(ucon.getHeaderField("Location"));
URLConnection conn = secondURL.openConnection();
Copied from java, android, resolve an url, get redirected uri

How to make REST API call using a token?

I am newbie developer in Java. STEP 1 I have already done the the following:
Logged in to REST API server (with login&password)
Received a token in XML format which i parsed with SAX parser so now i
am in a position of a token. Below is the sample code for Login:
Java code:
String url1 = "https://api4.liverail.com/login";
URL obj = new URL(url1);
HttpsURLConnection con1 = (HttpsURLConnection) obj.openConnection();
String urlParameters ="username=paania#gmail.com&password=d372a15b714bd250e";
con1.setDoOutput(true);
con1.setRequestMethod("POST");
DataOutputStream wr = new DataOutputStream(con1.getOutputStream());
wr.writeBytes(urlParameters);
STEP 2: I want to pass the token to REST API to obtain some information e.g a list from category but when i send the request via GET method , i get a response in XML saying [CDATA[You need to be logged in]] This is the code in Java:
String url = "http://api4.liverail.com/advertising/category/list/?token="72938howdwoi";
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("GET");
BufferedReader in = new BufferedReader(newInputStreamReader(con.getInputStream()));
in.close();
con.disconnect();
I am not sure what i am missing here.
Any suggestions?

Just changed your url for request of data :
String url = "http://api4.liverail.com/advertising/category/list/?token=72938howdwoi";

HTTPS Login using Java

I've a problem to login to a website via https.
I wrote this code (it works) for http access:
String user = user;
String password = psw;
String authString = user + ":" + password;
byte[] authEncBytes = Base64.encodeBase64(authString.getBytes());
String authStringEnc = new String(authEncBytes);
URLConnection connection= url.openConnection();
connection.setRequestProperty("Authorization", "Basic " + authStringEnc);
connection.setRequestProperty("Content-Type", "application/json");
connection.setRequestProperty("Accept", "application/json");
connection.connect();
I'd like to do the same things but via https. Is it possible?

You can, please use HttpsURLConnection
Checkout sample program on http://www.mkyong.com/java/java-https-client-httpsurlconnection-example/

When specifying your URL, make sure to pass "https://..."
url.openConnection();
will return you an object that has the type of the established connection. It will always be URLConnection, but it can be a class that extends URLConnection as well. Such classes are HttpURLConnection and HttpsURLConnection (and others).
You should verify that the returned object is of type HttpsURLConnection. And if it's not, you should stop the connection (in case you want to avoid non secure connections).
if (connection instanceof HttpsURLConnection)

Picasa getAlbum request not working Android

String album = "http://picasaweb.google.com/data/feed/api/user/"+email;
HttpURLConnection con = (HttpURLConnection) new URL(albumUrl).openConnection();
// request method, timeout and headers
con.setRequestMethod("GET") ;
con.setReadTimeout(15000);
con.setRequestProperty("Authorization", "GoogleLogin auth="+auth);
con.setRequestProperty("GData-Version", "2");
// set timeout and that we will process output
con.setReadTimeout(15000);
con.setDoOutput(true);
// connnect to url
con.connect();
// read output returned for url
BufferedReader reader = new BufferedReader(new InputStreamReader(con.getInputStream()));
Problem : Everytime i call con.getInputStream() it gives me file not found exception.
But when i load the same url in the desktop browser then it is displaying correct data.
I am confused why on android it is throwing exception.
Thanks in advance.

Did you get this? Maybe you just missed the https
below example uses default for authenticated user and the experimental fields list.
url = "https://picasaweb.google.com/data/feed/api/user/default?kind=album&access=public&fields="
+ URLEncoder
.encode("entry(title,id,gphoto:numphotosremaining,gphoto:numphotos,media:group/media:thumbnail)",
"UTF-8");
https://developers.google.com/picasa-web/docs/2.0/developers_guide_protocol#ListAlbums