I want to get the result of getServerResult() method but return "null". However, the Logcat inside the httpURLConnectionPost() method is normal which return "sucessful". Please answer me! why I got null outside the httpURLConnectionPost() method with getServerResult() method in this case?
private String serverResult;
public void httpURLConnectionPost(final String urlString){
new Thread(new Runnable() {
public void run() {
try {
URL url = new URL(urlString);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setUseCaches(false);
connection.connect();
String body = stringBuilder();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(connection.getOutputStream(), "UTF-8"));
writer.write(body);
writer.close();
int responseCode = connection.getResponseCode();
if(responseCode == HttpURLConnection.HTTP_OK){
InputStream inputStream = connection.getInputStream();
String line;
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
while ((line = bufferedReader.readLine()) != null) {
stringBuilderResult.append(line);
}
String result = stringBuilderResult.toString();
Log.d("MSG","result= "+result);
setServerResult(result);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();
}
public void setServerResult(String serverResult){
this.serverResult = serverResult;
}
public String getServerResult(){
return serverResult;
}
D/MSG: result = successful
using getServerResult() :
D/TAG: result = null
Where are you calling httpURLConnectionPost? Regardless you should be using an async task for this, functions that call HTTP requests are not going to return anything because the code is executing and finishing before the response is received.
You need to make sure the task is complete before trying to get any data. Usually you would use an async task and in the onPostExecute portion you would do something to let the app know that data is returned.
Related
I have a class, called FindMeARestaurantDAO, which contains methods that will make network calls to a server with AsyncTask inner classes in my Activity. I am having issues with my POST request Method, which is as follows:
#Override
public String findMeARestaurant(List<CheckboxDTO> filters) {
String inputLine;
String errors;
String result;
try
{
// For each CheckboxDTO, get the Id and add it to JSONArray
JSONArray checkboxJSONArray = new JSONArray();
for (CheckboxDTO checkbox : filters)
{
try
{
// Create JSONObject
JSONObject object = new JSONObject();
// Build the object
object.put("id", checkbox.getId());
// Add object to JSONArray
checkboxJSONArray.put(object);
}
catch (Exception e)
{
e.printStackTrace();
}
}
// Put JSONArray into wrapping JSONObject
JSONObject serverObject = new JSONObject();
try
{
// Create wrapping JSONObject
serverObject.put("filtersIds", checkboxJSONArray);
}
catch (Exception e)
{
e.printStackTrace();
}
// Create URL object to hold URL
URL findMeARestaurantURL = new URL(findMeARestaurantsURL);
// Create connection to server
HttpURLConnection connection = (HttpURLConnection) findMeARestaurantURL.openConnection();
// Set request method and timeouts
connection.setRequestMethod(FIND_RESTAURANT_REQUEST_METHOD);
connection.setRequestProperty("Content-Type", "application/json; utf-8");
connection.setRequestProperty("Accept", "application/json");
connection.setChunkedStreamingMode(0);
connection.setDoOutput(true);
connection.setReadTimeout(READ_TIMEOUT);
connection.setConnectTimeout(CONNECTION_TIMEOUT);
// Connect to server
connection.connect();
// Create Writer
Writer writer = new BufferedWriter(new OutputStreamWriter(connection.getOutputStream()));
writer.write(String.valueOf(serverObject));
// Close Writer
writer.close();
// Create InputStreamReader to read response from server
InputStreamReader streamReader = new InputStreamReader(connection.getInputStream(), "utf-8");
// Create BufferedReader to read through InputStream
BufferedReader reader = new BufferedReader(streamReader);
// Create StringBuilder to hold our result
StringBuilder stringBuilder = new StringBuilder();
// Check if the line read is null
while ((inputLine = reader.readLine()) != null){
stringBuilder.append(inputLine);
}
// Close out InputStream and BufferedReader
reader.close();
streamReader.close();
// Set result to stringBuilder
result = stringBuilder.toString();
connection.disconnect();
}
catch (IOException e)
{
e.printStackTrace();
return null;
}
return result;
}
The method is POST and it appears to send the JSON serverObject to the server when I run my application, but it fails on the InputStreamReader and returns a FileNotFoundException. The server was set up by a partner for this project and says this portion of the API should be working. Am I missing something for the POST request? Do I need to be doing something differently for reading the server's response? Any help would be greatly appreciated.
The solution to this issue was in how I sent the data to the server in a POST request. I had to send my filters' Ids to the server by adding them to my URL before establishing the connection. My modified method iterates through each CheckboxDTO and catches the Id, then adds it to an array, which is then added to the URL:
#Override
public String findMeARestaurant(List<CheckboxDTO> filters) {
String inputLine;
String result;
try
{
// For each CheckboxDTO, get the Id and add it to String Array
int checkboxArray[] = new int[filters.size()];
int i = 0;
for (CheckboxDTO checkbox : filters)
{
try
{
int id = checkbox.getId();
checkboxArray[i] = id;
i++;
}
catch (Exception e)
{
e.printStackTrace();
}
}
// Add filters to end of URL for POST Request
findMeARestaurantsURL += "?filterIds=";
for (i = 0; i < checkboxArray.length; i++)
{
if (i+1 != checkboxArray.length)
{
findMeARestaurantsURL += checkboxArray[i] + ",";
}
else
{
findMeARestaurantsURL += checkboxArray[i];
}
}
// Create URL object to hold URL
URL findMeARestaurantURL = new URL(findMeARestaurantsURL);
// Create connection to server
HttpURLConnection connection = (HttpURLConnection) findMeARestaurantURL.openConnection();
// Set request method and timeouts
connection.setRequestMethod(FIND_RESTAURANT_REQUEST_METHOD);
connection.setRequestProperty("Content-Type", "application/json; utf-8");
connection.setRequestProperty("Accept", "application/json");
connection.setChunkedStreamingMode(0);
connection.setDoOutput(true);
connection.setReadTimeout(READ_TIMEOUT);
connection.setConnectTimeout(CONNECTION_TIMEOUT);
// Connect to server
connection.connect();
// Create InputStreamReader to read response from server
InputStreamReader streamReader = new InputStreamReader(connection.getInputStream(), "utf-8");
// Create BufferedReader to read through InputStream
BufferedReader reader = new BufferedReader(streamReader);
// Create StringBuilder to hold our result
StringBuilder stringBuilder = new StringBuilder();
// Check if the line read is null
while ((inputLine = reader.readLine()) != null){
stringBuilder.append(inputLine);
}
// Close out InputStream and BufferedReader
reader.close();
streamReader.close();
// Set result to stringBuilder
result = stringBuilder.toString();
connection.disconnect();
}
catch (IOException e)
{
e.printStackTrace();
return null;
}
return result;
}
The server uses the Spring framework, and according to my partner, did not use a JSONObject.
When I Debug my code get Response code 200 which means success. Then also I'm getting null response.
Following is my AsyncTask Class:
private class AsyncAddfriend extends AsyncTask<String, String, String> {
HttpURLConnection conn;
URL url = null;
#Override
protected String doInBackground(String... params) {
try {
url = new URL("http://ishook.com/users/friends/send_friend_request_json/");
} catch (MalformedURLException e) {
e.printStackTrace();
}
try {
conn = (HttpURLConnection)url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
Uri.Builder builder = new Uri.Builder()
.appendQueryParameter("sessionId", params[0])
.appendQueryParameter("UserId", params[1])
.appendQueryParameter("friendId", params[2]);
String query = builder.build().getEncodedQuery();
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(query);
writer.flush();
writer.close();
os.close();
conn.connect();
} catch (IOException e) {
e.printStackTrace();
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Pass data to onPostExecute method
return(result.toString());
}else{
return("unsuccessful");
}
} catch (IOException e) {
e.printStackTrace();
return "exception";
} finally {
conn.disconnect();
}
}}
I have Tested My API in postman its Working with response code 200 and giving Response in json format but in my code its not working .
Hope you will understand my problem.
Thank you very much for your time and assistance in this matter.
The problem is probably from this line:
String query = builder.build().getEncodedQuery();
You need to use:
String query = builder.build().toString();
This is because getEncodedQuery() is only returning the query, from the documentation:
String getEncodedQuery ()
Gets the encoded query component from this URI. The query comes after the query separator ('?') and before the fragment separator ('#'). This method would return "q=android" for "http://www.google.com/search?q=android".
UPDATED
You're building the query after opening the connection, hence you having the error.
You need to build the url with the query first:
Uri uri = Uri.parse("http://ishook.com/users/friends/send_friend_request_json/")
.buildUpon()
.appendQueryParameter("sessionId", params[0])
.appendQueryParameter("UserId", params[1])
.appendQueryParameter("friendId", params[2]);
.build();
URL url = new URL(builtUri.toString());
conn = (HttpURLConnection)url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
conn.connect();
Note: I haven't test the code. So, don't expected it working automagically.
I'm actually srugling with my application using HttpUrlConnection, I tried the simplest code found on the internet and still got a FatalShutDown in the logcat and I don't understand the problem.
Here is the code :
try {
URL url = new URL("http://www.android.com/");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader r = new BufferedReader(new InputStreamReader(in));
StringBuilder total = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
total.append(line).append('\n');
}
response_textview.setText(total.toString());
urlConnection.disconnect();
}
catch (MalformedURLException e){
response_textview.setText(e.getMessage());
}
catch (IOException e){
response_textview.setText(e.getMessage());
}
And I got this in the logcat :
Thanks
Wrap your code with Asynktask doInBackground() method.
You need to make request in new thread. Probably, your code (it is only try catch) is running on main thread. This operation is denied. Try to use e.g. Thread.class to make request in new thread.
You shouldn't perform network operation on main thread. Use AsyncTask.
1. Create AsyncTask object and move your code into doInBackground method as mentioned below:
AsyncTask task = new AsyncTask<Void,String,String>(){
#Override
protected String doInBackground(Void... params) {
// perform your network operation here and return response
try {
URL url = new URL("http://www.android.com/");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader r = new BufferedReader(new InputStreamReader(in));
StringBuilder total = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
total.append(line).append('\n');
}
urlConnection.disconnect();
}
catch (MalformedURLException e){
return e.getMessage();
}
catch (IOException e){
return e.getMessage();
}
return total.toString();
}
protected void onPostExecute(String response){
// response returned by doInBackGround() will be received
// by onPostExecute(String response)
response_textview.setText(response);
}
};
2. Execute task
task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
I'm trying to use HttpURLConnection for connecting to server from Android app which I'm developing. For now, I'm testing the connection code not in an app but as a plain java program with main class. I guess this doesn't make any difference as far as HttpUrlConnection.
Please examine the code snippet. Another issue is even errorStream is throwing null. This I feel is because of malformed URL.
private static String urlConnectionTry() {
URL url; HttpURLConnection connection = null;
try {
String urlParameters = "email=" + URLEncoder.encode("email", "UTF-8") +
"&pwd=" + URLEncoder.encode("password", "UTF-8");
//Create connection
url = new URL("http://example.com/login");
connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
connection.setRequestProperty("uuid", getUuid());
connection.setDoInput(true);
connection.setDoOutput(true);
connection.setInstanceFollowRedirects(true);
//Send request
DataOutputStream wr = new DataOutputStream (
connection.getOutputStream ());
wr.writeBytes (urlParameters);
wr.flush ();
wr.close ();
//Get Response
InputStream is = connection.getErrorStream();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
String line;
StringBuffer response = new StringBuffer();
while((line = rd.readLine()) != null) {
response.append(line);
response.append('\r');
}
rd.close();
return response.toString();
} catch (Exception e) {
e.printStackTrace();
return null;
} finally {
if(connection != null) {
connection.disconnect();
}
}
}
private static String getUuid() {
try {
Document doc=Jsoup.connect("http://example.com/getUuid").get();
Elements metaElems = doc.select("meta");
for (Element metaElem : metaElems) {
if(metaElem.attr("name").equals("uuid")) {
return metaElem.attr("content");
}
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
You're probably receiving 401 because the credentials that was sent to the server is not authorized- it's probably not registered or the password is incorrect.
As for the null error stream, take a look at this SO answer.
If the connection was not connected, or if the server did not have an error while connecting or if the server had an error but no error data was sent, this method will return null.
It is probably better if you check first the response code using HttpUrlConnection#getResponseCode(). Decide on whether you'll be checking the contents of the error stream based on the response code you get.
I currently have a project where different parameters are requested from an online CGI file, and each request is supposed to be processed in different threads. When I run my code by itself it works great, however it doesn't seem to connect when I put it in a thread.
My code is below:
public void run() {
connect();
}
public synchronized void connect(){
StringBuffer response = new StringBuffer("");
try {
String data = "year=" + year + "&top=" + numNames + "number=";
// Send data
URL url = new URL("http://www.ssa.gov/cgi-bin/popularnames.cgi");
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(data);
wr.flush();
// Get the response
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String line;
while ((line = rd.readLine()) != null) {
response.append(line);
}
wr.close();
rd.close();
} catch (Exception e) {
System.out.println(e);
}
System.out.println(response);
}
}
Remove the synchronized call on connect. That should solve your problem
public synchronized void connect(){