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Getting Network is unreachable on IPV6 Network

I am getting "Network is Unreachable" from below Java Http request for any url.
Below code is working fine with IPV4 network.
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setDoOutput(true);
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())));
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();
}
Please help me on this issue.

If you are specifying the IPv6 URL using the IP address, you need to enclose it in square brackets since the :: in the address are special characters in a URL.
See RFC 2732.

Can't send data with the use of POST request from Java to PHP

I am trying to send data from Java code to PHP code with the use of a POST request. For some reason on the PHP side I get nothing at all, but my code "works" (no exception occurs). What can be the problem? Thanks in advance!
My data looks something like this:
"data=" + sb.toString()
And the code can be found here below:
public static void sendRequest(String encryptedString) {
HttpURLConnection connection = null;
BufferedReader br = null;
DataOutputStream dos = null;
try {
connection = (HttpURLConnection) new URL("http://localhost/something/function").openConnection();
connection.setDoOutput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setFixedLengthStreamingMode(encryptedString.length());
dos = new DataOutputStream(connection.getOutputStream());
dos.writeBytes(encryptedString);
dos.flush();
br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
System.out.println("Can't create connection...");
e.printStackTrace();
} finally {
try {
if(dos != null) dos.close();
if(connection != null) connection.disconnect();
if(br != null) br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
PS: The picture:

The problem was that I encrypted the whole data=randomnumber thing with SHA-1. The data= part should not be encrypted and needs to be added later.

How to get the response data from cloud to string

I want to get the response to a string variable from the data from the cloud.
ClientResource cr = new ClientResource("http://localhost:8888/users");
cr.setRequestEntityBuffering(true);
try {
try {
cr.get(MediaType.APPLICATION_JSON).write(System.out);
} catch (IOException e) {
e.printStackTrace();
}
} catch (ResourceException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
I have response as JSON in the console and I want to convert it to string , Is the GSON library would be helpful? I haven't used it yet .What modifications should I need to do in my codes? Can anybody help me here.

In fact, Restlet receives the response payload as String and you can directly have access to this, as described below:
ClientResource cr = new ClientResource("http://localhost:8888/users");
cr.setRequestEntityBuffering(true);
Representation representation = cr.get(MediaType.APPLICATION_JSON);
String jsonContentAsString = representation.getText();
Hope it helps you,
Thierry

Below is a working example:
try {
URL url = new URL("http://localhost:8888/users");
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("Raw 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();
}
}

FileNotFoundException on HttpsURLConnection with POST and unmutable doOutput variable

I'm trying to POST some data to an https url, in my android application, in order to get a json format response.
I'm facing two problems:
is = conn.getInputStream();
throws
java.io.FileNotFoundException
I don't get if i do something wrong with HttpsURLConnection.
The second problem arose when i debug the code (used eclipse); I set a breakpoint after
conn.setDoOutput(true);
and, when inspecting conn values, I see that the variable doOutput remain set to false and type GET.
My method for https POST is the following, where POSTData is a class extending ArrayList<NameValuePair>
private static String httpsPOST(String urlString, POSTData postData, List<HttpCookie> cookies) {
String result = null;
HttpsURLConnection conn = null;
OutputStream os = null;
InputStream is = null;
try {
URL url = new URL(urlString);
conn = (HttpsURLConnection) url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setUseCaches (false);
conn.setDoInput(true);
conn.setDoOutput(true);
if(cookies != null)
conn.setRequestProperty("Cookie",
TextUtils.join(";", cookies));
os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(postData.getPostData());
writer.flush();
writer.close();
is = conn.getInputStream();
BufferedReader r = new BufferedReader(
new InputStreamReader(is));
StringBuilder total = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
total.append(line);
}
result = total.toString();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (os != null) {
try {
os.close();
} catch (IOException e) {
}
}
if (is != null) {
try {
is.close();
} catch (IOException e) {
}
}
if (conn != null) {
conn.disconnect();
}
}
return result;
}
A little update: apparently eclipse debug lied to me, running and debugging on netbeans shows a POST connection. Error seems to be related to parameters i'm passing to the url.

FileNotFoundException means that the URL you posted to doesn't exist, or couldn't be mapped to a servlet. It is the result of an HTTP 404 status code.
Don't worry about what you see in the debugger if it doesn't agree with how the program behaves. If doOutput really wasn't enabled, you would get an exception obtaining the output stream.

Java, FileNotfound Exception, While reading conn.getInputStream()

Please tell me some one, How to resolve this problem,
Sometime I am getting Filenotfound Exception and Some time this code working fine.
Below is my code,
public String sendSMS(String data, String url1) {
URL url;
String status = "Somthing wrong ";
try {
url = new URL(url1);
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
conn.setRequestProperty("User-Agent","Mozilla/5.0 ( compatible ) ");
conn.setRequestProperty("Accept","*/*");
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(data);
wr.flush();
// Get the response
try {
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String s;
while ((s = rd.readLine()) != null) {
status = s;
}
rd.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
wr.close();
} catch (MalformedURLException e) {
status = "MalformedURLException Exception in sendSMS";
e.printStackTrace();
} catch (IOException e) {
status = "IO Exception in sendSMS";
e.printStackTrace();
}
return status;
}

Rewrite like this and let me know how you go... (note closing of reading and writing streams, also the cleanup of streams if an exception is thrown).
public String sendSMS(String data, String url1) {
URL url;
OutputStreamWriter wr = null;
BufferedReader rd = null;
String status = "Somthing wrong ";
try {
url = new URL(url1);
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
conn.setRequestProperty("User-Agent","Mozilla/5.0 ( compatible ) ");
conn.setRequestProperty("Accept","*/*");
wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(data);
wr.flush();
wr.close();
rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String s;
while ((s = rd.readLine()) != null) {
status = s;
}
rd.close();
} catch (Exception e) {
if (wr != null) try { wr.close(); } catch (Exception x) {/*cleanup*/}
if (rd != null) try { rd.close(); } catch (Exception x) {/*cleanup*/}
e.printStackTrace();
}
return status;
}

This issue seems to be known, but for different reasons so its not clear why this happend.
Some threads would recommend closing the OutputStreamWriter as flushing it is not enough, therefor i would try to clos it directly after fushing as you are not using it in the code between the flush and close.
Other threads show that using a different connections like HttpURLConnection are avoiding this problem from occuring (Take a look here)
Another article suggests to use the URLEncoder class’ static method encode. This method takes a string and encodes it to a string that is ok to put in a URL.
Some similar questions:
URL is accessable with browser but still FileNotFoundException with URLConnection
URLConnection FileNotFoundException for non-standard HTTP port sources
URLConnection throwing FileNotFoundException
Wish you good luck.

It returns FileNotFoundException when the server response to HTTP request is code 404.
Check your URL.