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Unable to read 404 error response body from azure

I am trying to read the response body for an error response(404,400,500) using java application and basic http client. When testing in my local , I am able to get the proper json response. But when I deployed to azure I am getting the error response body in HTML tags.
Error response I got when deployed to azure and testing from there:
400 Error400 error while attempting to access resource
#AddLoggerInAppInsights
public Map exchangeNativeHttpRequest(String url, String jsonPayLoad, String correlationId) {
Map<String,Object> responseMap = null;
try {
URL httpUrl = new URL(url);
HttpURLConnection conn = (HttpURLConnection) httpUrl.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setRequestProperty("Accept", "application/json");
conn.setRequestProperty(CLIENT_ID_KEY, System.getenv(CLIENT_ID_VALUE));
conn.setRequestProperty(CLIENT_SECRET_KEY, System.getenv(CLIENT_SECRET_VALUE));
conn.setRequestProperty(CORRELATION_ID, correlationId);
OutputStream os = conn.getOutputStream();
os.write(jsonPayLoad.getBytes());
os.flush();
HttpStatus httpStatus = HttpStatus.valueOf(conn.getResponseCode());
BufferedReader br = null;
if (conn.getResponseCode() == org.apache.http.HttpStatus.SC_OK) {
br = new BufferedReader(new InputStreamReader(
(conn.getInputStream())));
}else if (conn.getResponseCode() == org.apache.http.HttpStatus.SC_BAD_REQUEST){
br = new BufferedReader(new InputStreamReader(
(conn.getErrorStream())));
}else {
throw new RuntimeException("Failed : HTTP error code : "
+ conn.getResponseCode());
}
String output;
StringBuilder sb = new StringBuilder();
while ((output = br.readLine()) != null) {
sb.append(output);
}
telemetryClient.trackEvent(correlationId+":" +"Response for Create Breakdown IBMI API from HTTP_CONNECTION: "+sb.toString());
responseMap = new HashMap<>();
responseMap.put("statusCode",httpStatus);
responseMap.put("response", sb.toString());
conn.disconnect();
} catch (MalformedURLException e) {
telemetryClient.trackException(e);
} catch (IOException e) {
telemetryClient.trackException(e);
}
telemetryClient.trackEvent(correlationId+":" +"Returned Response of Create Breakdown IBMI API from HTTP_CLIENT: "+responseMap.toString());
return responseMap;
}

Could somebody explain me how consume web services(REST JSON) made in php from java desktop?

I got this example code but the response is an "Exception in NetClientGet:- java.net.SocketException: Permission denied: connect"
I'm using jdk 1.8.
This is my example code:
try {
URL url = new URL("http://localhost/ServiciosWebLT/peoples");//your url i.e fetch data from .
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
conn.setDoOutput(true);
if (conn.getResponseCode() != 200) {
throw new RuntimeException("Failed : HTTP Error code : "
+ conn.getResponseCode());
}
InputStreamReader in = new InputStreamReader(conn.getInputStream());
BufferedReader br = new BufferedReader(in);
String output;
while ((output = br.readLine()) != null) {
System.out.println(output);
}
conn.disconnect();
} catch (Exception e) {
System.out.println("Exception in NetClientGet:- " + e);
}
thanks in advance.

Want to make perl code for oauth2 work in Java "curl -H 'Authorization: Bearer:<TOKEN> https://canvas.instructure.com/api/v1";

I am getting an error that I am unauthorized.. RESPONSE CODE 401
The token I am using works in perl..
This is what I have tried till now:
public static void main(String[] args) throws Exception {
try {
String auth = returnAuth(); //getting token from a file.
//System.out.println(auth);
String url1= "https://canvas.instructure.com/api/v1";
URL url = new URL(url1+"/courses");
HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
connection.setRequestMethod("GET");
//connection.setRequestProperty("Authorization", "Bearer " + auth);
connection.setRequestProperty("Authorization", "Bearer "+auth);
System.out.println("\nSending 'GET' request to URL : " + url);
System.out.println("Response code:" + connection.getResponseCode());
System.out.println("Response message:" + connection.getResponseMessage());
// Read the response:
BufferedReader reader = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
String line;
StringBuffer response = new StringBuffer();
while ((line = reader.readLine()) != null) {
response.append(line);
}
reader.close();
System.out.println(response.toString());
}
catch (MalformedURLException e1) {
e1.printStackTrace();
} catch (IOException e2) {
e2.printStackTrace();
}
}

public static void main(String[] args) throws Exception {
try {
String auth = returnAuth(); //getting token from a file.
String url1= "https://canvas.instructure.com/api/v1/courses";
URL url = new URL(url1);
HttpsURLConnection connection =(HttpsURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setRequestProperty("Authorization", "Bearer "+auth);
System.out.println("\nSending 'GET' request to URL : " + url);
System.out.println("Response code:" + connection.getResponseCode());
System.out.println("Response message:" + connection.getResponseMessage());
// Read the response:
BufferedReader reader = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
reader.close();
}
catch (MalformedURLException e1) {
e1.printStackTrace();
} catch (IOException e2) {
e2.printStackTrace();
}
}

You have it commented out but every Oauth server I've dealt with would be "Bearer <token>" - one space and no colon.

You set the parameters AFTER you called!
Change your code to first set the authentication, then open the connection.
String url1= "https://canvas.instructure.com/api/v1";
URL url = new URL(url1+"/courses");
connection.setRequestProperty("Authorization", "Bearer "+auth);
connection.setRequestMethod("GET");
//now you can open the connection...
HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();

RESTClient using HTTP Get Request

I am trying to write a JSON Client which uses HTTP GET method,and I am getting an response of 500.The code I have tried is below,Is there any wrong with the same?The request parameter I am trying to set is entityName=Nila and parentEntity=500000001 as parameters.
URL url = new URL("http://192.168.210.74:9763/services/testEntityService?entityName=Nila&parentEntity=500000001");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
if (conn.getResponseCode() != 200) {
throw new RuntimeException("Failed : HTTP error code : "
+ conn.getResponseCode());
}
BufferedReader br = new BufferedReader(new InputStreamReader(
(conn.getInputStream())));
String output;
System.out.println("Output from Server .... \n");
while ((output = br.readLine()) != null) {
System.out.println(output);
}
conn.disconnect();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

Its an internal server error yes the problem is on server side.

Android POST Request 400 Response code throws Exception

When i send a POST Request to a Server, if the response is 200 i get the JSON body. However for unsuccessful requests the servers send a 400 response code but my android code throws a FileNotFoundException. Is there any difference between reading a 400 response and a 200 response ?
StringBuffer responseBuilder = new StringBuffer();
String line = null;
HttpURLConnection conn = null;
OutputStream out = null;
BufferedReader rd = null;
System.setProperty("http.keepAlive", "false");
try
{
conn = (HttpURLConnection) new URL(requestURL).openConnection();
conn.setRequestMethod("POST");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setUseCaches(false);
conn.setAllowUserInteraction(false);
conn.setConnectTimeout(NetworkConstants.CONNECTION_TIMEOUT);
conn.setReadTimeout(NetworkConstants.SOCKET_TIMEOUT);
out = conn.getOutputStream();
Writer writer = new OutputStreamWriter(out, "UTF-8");
String s = formatParams();
Log.d("-------------------------------------------------->", s);
writer.write(s);
writer.flush();
writer.close();
}
catch (Exception e)
{
}
finally
{
if (out != null)
{
try
{
out.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
try
{
rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = rd.readLine()) != null)
{
responseBuilder.append(line);
if (!rd.ready())
{
break;
}
}
}
catch (Exception e)
{
e.printStackTrace();
}
finally
{
if (conn != null)
{
conn.disconnect();
}
}
String response = responseBuilder.toString();
Log.d("###########################", response);
return response;
Kind Regards,

Use getErrorStream() for this. From the docs:
If the HTTP response indicates that an error occurred, getInputStream() will throw an IOException. Use getErrorStream() to read the error response. The headers can be read in the normal way using getHeaderFields().
Sample code:
httpURLConnection.connect();
int responseCode = httpURLConnection.getResponseCode();
if (responseCode >= 400 && responseCode <= 499) {
Log.e(TAG, "HTTPx Response: " + responseCode + " - " + httpURLConnection.getResponseMessage());
in = new BufferedInputStream(httpURLConnection.getErrorStream());
}
else {
in = new BufferedInputStream(httpURLConnection.getInputStream());
}
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line = "";
while ((line = reader.readLine()) != null) {
urlResponse.append(line);
}

If the response code isn't 200 or 2xx, use getErrorStream() instead of getInputStream() to parse the json and show the message provided by your backend.

I know it's been a long time since the question was asked but for the benefit of other people who are still having this kind of problem please note that another possible cause of the problem is using "connection.getContent()" to get InputStream. like so:
InputStream is = (InputStream) connection.getContent();
this can create a problematic situation where response code larger than 399 will not be processed at all.
so the recommendation is to work directly with getInputStream() and getErrorStream() as shown in previous comments and as in the following example:
HttpURLConnection connection = null;
BufferedReader bufferedReader = null;
try {
String urlString = "http://www.someurl.com";
URL url = new URL(urlString);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream is;
int responseCode = connection.getResponseCode();
if (responseCode < HttpURLConnection.HTTP_BAD_REQUEST) {
is = connection.getInputStream();
} else {
is = connection.getErrorStream();
}
StringBuilder response = new StringBuilder();
bufferedReader = new BufferedReader(new InputStreamReader(is));
String tempLine;
while ((tempLine = bufferedReader.readLine()) != null) {
response.append(tempLine);
}
String serverResponse = response.toString();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (connection != null) {
connection.disconnect();
}
}