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How to stop a string from being cut off in Java

I have a java code to call a REST API which returns a JWT token as a response. I send a GET call to the API and it will return a JWT token as a response. The token is being returned fine. However, I've noticed somehow the token is being trimmed.
I tried everything online and nothing seems to be working for me. Below is my code :
try {
URL url = new URL(proxyService.getProperty("proxy.url") + "/" + sessionToken);
log.logText("Connection URL: " + url, logLevel);
String readLine = null;
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
int responseCode = conn.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
InputStream in = ((URLConnection)conn).getInputStream();
int length = 0;
StringBuffer response = new StringBuffer();
byte[] data1 = new byte[1024];
while (-1 != (length = in.read(data1))) {
response.append(new String(data1, 0, length));
}
log.logText("JSON String Result: " + response.toString(), logLevel);
}
conn.disconnect();
} catch(MalformedURLException e) {
e.printStackTrace();
} catch(IOException e) {
e.printStackTrace();
}
oauthToken = oauthToken.replaceAll("^\"|\"$", "");
log.logText("OAuth2 Token: " + oauthToken, logLevel);
return oauthToken;
Regards,
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As #markspace mentioned, please specify the data type for oauthToken (I believe it is of type String). Print the total String and then the length before replaceALL and after replaceALL. compare whats replace adds to the total length if yes then there is no issue of string getting trimmed.

You are not assigning response value to anything. I assume you should be assigning it to oauthToken variable.
Also please close the InputStream instance in finally clause, otherwise you will cause resource leakage.

I think you have to close InputStream first, to flush internal buffer.
public static String getOauthToken() throws IOException {
URL url = new URL(proxyService.getProperty("proxy.url") + "/" + sessionToken);
log.logText("Connection URL: " + url, logLevel);
String oauthToken = readInputString(url);
oauthToken = oauthToken.replaceAll("^\"|\"$", "");
log.logText("OAuth2 Token: " + oauthToken, logLevel);
return oauthToken;
}
private static String readInputString(URL url) throws IOException {
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
if (conn.getResponseCode() != HttpURLConnection.HTTP_OK)
throw new RuntimeException("Not expected response code");
try (InputStream in = conn.getInputStream()) {
StringBuffer buf = new StringBuffer();
byte[] b = new byte[1024];
while (true) {
int readBytes = in.read(b);
if (readBytes == -1)
break;
buf.append(new String(b, 0, readBytes));
}
log.logText("JSON String Result: " + buf, logLevel);
return buf.toString();
}
}

It looks like the actual application that I'm calling from is cutting off the response value. I shortened the length of the JWT token and it's not cutting it off. The application must have a limit for a maximum number of characters allowed in a string could be for performance reasons.

Android - Size in chars of an http response

I am not an pro developing android. I wanted to download a JSON object from my server, but only code I could find was this:
private String downloadUrl(String myurl) throws IOException {
InputStream is = null;
// Only display the first 500 characters of the retrieved
// web page content.
int len = 500;
try {
URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000 /* milliseconds */);
conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestMethod("GET");
conn.setDoInput(true);
// Starts the query
conn.connect();
int response = conn.getResponseCode();
Log.d("ServerConnection", "The response is: " + response);
is = conn.getInputStream();;
//is.
// Convert the InputStream into a string
String contentAsString = readIt(is, len);
return contentAsString;
// Makes sure that the InputStream is closed after the app is
// finished using it.
} catch (MalformedURLException e) {
//
return "error";
} catch (IOException e) {
//
return "error";
} finally {
if (is != null) {
is.close();
}
}
}
And it works fine, I cant understand. But it has a int len = 500, and my returned json is cropped to 500 chars. I tried changing to a great number, but it puts spaces at the end. How can I know the size in chars of the String contained by the InputSteam?
Thanks

You can check the Content-Length header value of your response:
Map<String, List<String>> headers = connection.getHeaderFields();
for (Entry<String, List<String>> header : headers.entrySet()) {
if(header.getKey().equals("Content-Legth")){
len=Integer.parseInt(header.getValue());
}
}
or you can your response in a buffered reader like this:
InputStream is = connection.getInputStream();
InputStreamReader reader = new InputStreamReader(is);
StringBuilder builder = new StringBuilder();
int c = 0;
while ((c = reader.read()) != -1) {
builder.append((char) c);
}

Yout can use Apache Commons IO IOUtils.toString to convert InputStream to String or use Gson to read object from input stream directly:
return gson.fromJson(new InputStreamReader(inputStream), YourType.class);

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.

HTTP GET request in java returns meaningless data from App Engine

I'm requesting a json file from an App Engine URL
http://1-1-26a.wordbuzzweb.appspot.com/json/level-images.json
The file encoding is UTF-8 without a BOM. If I look at this file on my local disk it's size is 12414 bytes. If I get the file in Chrome is reads it perfectly well. If I then save it it's 12414 bytes. However, if I try and download the file with a GET request in java I only get 780 bytes returned and the returned data would appear to be meaningless.
I've tried several different types of get request, both of the methods below I have used elsewhere perfectly effectively. The response code on the GET requests is 200. Interestingly, if I do a POST with no content instead of a GET, then I get the valid response.
If I download the file from this URL on Google Drive instead, then the GET methods below work perfectly.
edit This code is now working, however, this is a recurring issue that comes and goes. If anyone has any ideas what might be causing it then please say so!
This doesn't work
public static String doGetSync(String urlToRead) throws IOException {
URL url = new URL(urlToRead);
InputStream is = url.openStream();
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
int nRead;
byte[] data = new byte[BUFFER_SIZE];
while ((nRead = is.read(data, 0, data.length)) != -1) {
buffer.write(data, 0, nRead);
}
buffer.flush();
byte[] bytes = buffer.toByteArray();
return new String(bytes, "UTF-8");
}
Neither does this
public static String doGetSync2(String urlToRead) throws IOException {
final String charset = "UTF-8";
// Create the connection
HttpURLConnection connection = (HttpURLConnection) new URL(urlToRead).openConnection();
// Check the error stream first, if this is null then there have been no issues with the request
InputStream inputStream = connection.getErrorStream();
if (inputStream == null)
inputStream = connection.getInputStream();
// Read everything from our stream
BufferedReader responseReader = new BufferedReader(new InputStreamReader(inputStream, charset));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = responseReader.readLine()) != null) {
response.append(inputLine);
}
responseReader.close();
return response.toString();
}
This code works
public static String doPostSync(final String url, final String content) throws IOException {
final String charset = "UTF-8";
// Create the connection
HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
// setDoOutput(true) implicitly set's the request type to POST
connection.setDoOutput(true);
connection.setRequestProperty("Accept-Charset", charset);
connection.setRequestProperty("Content-type", "application/json");
// Write to the connection
OutputStream output = connection.getOutputStream();
output.write(content.getBytes(charset));
output.close();
// Check the error stream first, if this is null then there have been no issues with the request
InputStream inputStream = connection.getErrorStream();
if (inputStream == null)
inputStream = connection.getInputStream();
// Read everything from our stream
BufferedReader responseReader = new BufferedReader(new InputStreamReader(inputStream, charset));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = responseReader.readLine()) != null) {
response.append(inputLine);
}
responseReader.close();
return response.toString();
}

Grabbing JSON works from one link, not from another

I'm doing a simple JSON grab from two links with the same code. I'm doing it two separate times, so the cause of my issue isn't because they're running into each other or something.
Here is my code:
#Override
protected String doInBackground(Object... params) {
try {
URL weatherUrl = new URL("my url goes here");
HttpURLConnection connection = (HttpURLConnection) weatherUrl
.openConnection();
connection.connect();
responseCode = connection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
InputStream inputStream = connection.getInputStream();
Reader reader = new InputStreamReader(inputStream);
int contentLength = connection.getContentLength();
char[] charArray = new char[contentLength];
reader.read(charArray);
String responseData = new String(charArray);
Log.v("test", responseData);
When I try this with:
http://www.google.com/calendar/feeds/developer-calendar#google.com/public/full?alt=json
I get an error of having an array lenth of -1
For this link:
http://api.openweathermap.org/data/2.5/weather?id=5815135
It returns fine and I get a log of all of the JSON. Does anyone have any idea why?
Note: I tried stepping through my code in debug mode, but I couldn't catch anything. I also downloaded a Google chrome extension for parsing json in the browser and both urls look completely valid. I'm out of ideas.

Log this: int contentLength = connection.getContentLength();
I don't see the google url returning a content-length header.
If you just want String output from a url, you can use Scanner and URL like so:
Scanner s = new Scanner(new URL("http://www.google.com").openStream(), "UTF-8").useDelimiter("\\A");
out = s.next();
s.close();
(don't forget try/finally block and exception handling)
The longer way (which allows for progress reporting and such):
String convertStreamToString(InputStream is) throws UnsupportedEncodingException {
BufferedReader reader = new BufferedReader(new
InputStreamReader(is, "UTF-8"));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null)
sb.append(line + "\n");
} catch (IOException e) {
// Handle exception
} finally {
try {
is.close();
} catch (IOException e) {
// Handle exception
}
}
return sb.toString();
}
}
and then call String response = convertStreamToString( inputStream );