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Issue with Retrieving JSON from Webpage Android

So I'm facing some difficulty in trying to, what seems simply, obtain a JSON file from a webpage, and then parse it on Android. I have already built the parser, and tested it in Eclipse (in fact, all of the code works in Eclipse). However, when I run the HttpURLConnection and try to retrieve the JSON data in a string in Android Studio, I end up getting no exceptions and an almost empty string (I think I am getting the 1st, 2nd, 3rd, and last character, but not too sure). I have included parts of the code below, and
URL url = null;
HttpURLConnection urc = null;
try {
url = new URL(query);
urc = (HttpURLConnection) url.openConnection();
InputStream in = new BufferedInputStream(urc.getInputStream());
jsoncontent = readStream(in);
System.out.println(jsoncontent);
} catch (MalformedURLException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
finally {
urc.disconnect();
}
The code for readStream() is below
private static String readStream(InputStream is) throws IOException {
StringBuilder sb = new StringBuilder();
BufferedReader r = new BufferedReader(new InputStreamReader(is),1000);
for (String line = r.readLine(); line != null; line =r.readLine()){
sb.append(line);
}
is.close();
return sb.toString();
}

Here is an exact chunk from an assignment I did last semester:
URL u = new URL(url);
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "text/html");
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
JSONObject searchResults = new JSONObject(in.readLine());
...
conn.disconnect();
You seem to be missing setRequestMethod("GET") and setRequestProperty("Accept", "text/html") in your code. Hope this helps.

How to guarantee a java POST request string / text to be UTF-8 encoding

I have a textmessage/string with letters like ä,ü,ß. I want everything to be UTF-8 encoded. When I write to a file or print the string to console, everything is fine. But when I want to send the same string to a web service, I get instead of ä,ü,ß the following �
I read the file from a Servlet.
Do I really have to use the following 2 lines to get a UTF-8 encoded text?
byte [] bray = text.getBytes("UTF-8");
text = new String(bray);
.
public static String readAsStream_UTF8(String filePathName){
String text ="";
InputStream input = Thread.currentThread().getContextClassLoader().getResourceAsStream("resources/"+filePathName);
if(input == null){
System.out.println("Inputstream null.");
}else{
InputStreamReader isr = null;
try {
isr = new InputStreamReader((InputStream)input, "UTF-8");
BufferedReader reader = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
String sCurrentLine;
while ((sCurrentLine = reader.readLine()) != null) {
sb.append(sCurrentLine);
}
text= sb.toString();
//it works only if I use the following 2 lines
byte [] bray = text.getBytes("UTF-8");
text = new String(bray);
} catch (Exception e1) {
e1.printStackTrace();
}
}
return text;
}
My sendPOST method looks something like the following:
String charset = "UTF-8";
OutputStreamWriter writer = null;
HttpURLConnection con = null;
String response_txt ="";
InputStream iss = null;
try {
URL url = new URL(urlService);
con = (HttpURLConnection)url.openConnection();
con.setDoOutput(true); //triggers POST
con.setDoInput(true);
con.setRequestMethod("POST");
con.setRequestProperty("accept-charset", charset);
//con.setRequestProperty("Content-Type", "application/soap+xml");
con.setRequestProperty("Content-Type", "application/soap+xml;charset=UTF-8");
writer = new OutputStreamWriter(con.getOutputStream());
writer.write(msg); //send POST data string
writer.flush();
writer.close();
What do I have to do to force the msg, that will be sent to the web service, to really be UTF-8 encoded.

If you know the encoding of the file which you want to send you don't need to convert it to an intermediary string. Simply copy its bytes to the output:
// inputstream to a UTF-8 encoded resource file
InputStream in = Thread.currentThread().getContextClassLoader().getResourceAsStream("resources/"+filePathName);
HttpURLConnection con = ...
// set contenttype and encoding
con.setRequestProperty("Content-Type", "application/soap+xml;charset=UTF-8");
// copy input to output
copy(in, con.getOutputStream());
using some copy function.
Additionally you could also set the Content-Length header to the size of the resource file.

Java CURL request using HTTP

I am trying to perform a CURL request using Java. The CURL request is as follows:
curl https://apis.sen.se/v2/feeds/N4hSBSpFlYzXT6ZN2IA1KadgSR9rTazv/events/?limit=1 -u username:password
I am trying to perform the request as follows:
String stringUrl = "https://apis.sen.se/v2/feeds/N4hSBSpFlYzXT6ZN2IA1KadgSR9rTazv/events/?limit=1";
URL url = new URL(stringUrl);
URLConnection uc = url.openConnection();
uc.setRequestProperty("X-Requested-With", "Curl");
String userpass = "username" + ":" + "password";
String basicAuth = "Basic " + new String(new Base64().encode(userpass.getBytes()));
uc.setRequestProperty("Authorization", basicAuth);
InputStreamReader inputStreamReader = new InputStreamReader(uc.getInputStream());
and I am trying to see the contents of inputStreamReader as follows:
int data = inputStreamReader.read();
char aChar = (char) data;
System.out.println(aChar);
The code is compiling and running fine, but it is returning nothing. Where am I going wrong?

I ended up getting it working using the following code:
public static void main(String args[]) throws IOException {
String stringUrl = "url";
URL url = new URL(stringUrl);
URLConnection uc = url.openConnection();
uc.setRequestProperty("X-Requested-With", "Curl");
String userpass = "username" + ":" + "password";
String basicAuth = "Basic " + new String(new Base64().encode(userpass.getBytes()));
uc.setRequestProperty("Authorization", basicAuth);
StringBuilder html = new StringBuilder();
BufferedReader input = null;
try {
input = new BufferedReader(new InputStreamReader(uc.getInputStream()));
String htmlLine;
while ((htmlLine = input.readLine()) != null) {
html.append(htmlLine);
}
}
catch (IOException e) {
e.printStackTrace();
}
finally {
try {
input.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
System.out.println(html.toString());
}

I was also trying to do that thing. I have some kind of workaround but it reads everything it sees.
--Here's the code---
String params = "some-parameters";
URL url = new URL("some-website");
HttpURLConnection con = (HttpURLConnection) url.openConnection();
con.setRequestMethod("POST");
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(params);
wr.flush();
wr.close();
con.getResponseCode();
BufferedReader reader = new BufferedReader(new InputStreamReader(con.getInputStream()));
String line;
StringBuffer buffer = new StringBuffer();
while((line = reader.readLine()) != null) {
buffer.append(line+"\n");
}
reader.close();
System.out.print(buffer.toString());
--Notice, I use this code to see if a certain account exist on a certain website, since it outputs everything, what I do is to find a specific regularity upon the code which could tell me if that user exist or not. Well I'm not really even sure if this could help you, but it might be. Good Luck...

How to escape the NÃO while reading the URL

InputStream in = address.openStream();
URL url = new URL("://www.mydomain.com/?param1=NÃO&param2=NÃO");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
StringBuilder result = new StringBuilder();
String line;
while((line = reader.readLine()) != null) {
result.append(line);
}
System.out.println(result.toString());
But when i am trying to put the result into StringBuilder the NÃO Special character à is getting escaped
How to bring it with out losing the char set value ?

I believe you want to use URLEncoder.encode(String, String) to encode your parameter like
try {
String value = URLEncoder.encode("NÃO", "utf-8");
String url = "://www.mydomain.com/?param1=" + value + "&param2="
+ value;
System.out.println(url);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
Output is
://www.mydomain.com/?param1=N%C3%83O&param2=N%C3%83O

Web content is different using Java than in browser

I have strange problem with BufferedReader reading from web.
This URL content is different in browsers than in pasted Java code.
In content fetched using Java first elements result is empty in browser it is not.
My code:
public static void main(String[] args) {
try {
String url = "https://api.freebase.com/api/service/mqlread?queries={\"q1\":{\"query\":[{\"name\":\"Pulp Fiction\",\"*\":null,\"type\":\"/film/film\"}]},\"q3\":{\"query\":[{\"name\":\"Portal\",\"*\":null,\"type\":\"/cvg/computer_videogame\"}]}}";
URL u = new URL(url);
System.out.println(u.toString());
URLConnection urlConn = u.openConnection();
InputStreamReader is = new InputStreamReader(urlConn.getInputStream());
BufferedReader br = new BufferedReader(is);
String line = null;
String data = "";
while ((line = br.readLine()) != null) {
data += line + "\n";
}
br.close();
System.out.println(data);
} catch (Exception ex) {
System.err.println(ex);
}
}
EDIT: Ahh. Figured it out. No space characters in URLs. Just replace them with %20.