I don't know why i get a null value when i call the GetPHPData() function. The "out" variable returns nothing (""). I make a Toast.makeTest and it returns empty string. Please help. This is my code:
public class PHPConnect extends Activity
{
String url = "http://122.2.8.226/MITBookstore/sqlconnect.php";
HttpURLConnection urlConnection = null;
String out = null;
public String GetPHPData()
{
try {
urlConnection = (HttpURLConnection) new URL(url).openConnection();
urlConnection.setConnectTimeout(5000);
urlConnection.setReadTimeout(10000);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try
{
BufferedReader in = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
out = readStream(in);
}
catch (Exception e)
{
Toast.makeText(getApplicationContext(),e.getMessage(),Toast.LENGTH_SHORT).show();
}
finally
{
urlConnection.disconnect();
return out;
}
}
private String readStream(BufferedReader is)
{
try
{
ByteArrayOutputStream bo = new ByteArrayOutputStream();
int i = is.read();
while(i != -1)
{
bo.write(i);
i = is.read();
}
return bo.toString();
} catch (IOException e)
{
return e.getMessage();
}
}
}
By the way, im running a wamp server and I port forwarded my router, on local host, the url works, but on remote connection, it won't return a string. You can try out the url, the result is: "This is the output:emil"
Can you please try below piece of code which is working for me, also add INTERNET permission in android manifest file. Still if it is not working then may be issue with server end then try to debug it.
URL url;
try {
url = new URL("myurl");
HttpURLConnection urlConnection = (HttpURLConnection) url
.openConnection();
InputStream in = urlConnection.getInputStream();
InputStreamReader isw = new InputStreamReader(in);
int data = isw.read();
while (data != -1) {
char current = (char) data;
data = isw.read();
System.out.print(current);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Related
Ive got
HttpURLConnection urlConnection = null;
String result = "";
try {
String host = "http://www.example.com/json.json";
URL url = new URL(host);
urlConnection = (HttpURLConnection) url.openConnection();
int code = urlConnection.getResponseCode();
if(code==200){
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
if (in != null) {
JSONParser jsonParser = new JSONParser();
JSONObject jsonObject = (JSONObject)jsonParser.parse(new InputStreamReader(in, "UTF-8"));
result=(String) jsonObject.get("name");
System.out.print(jsonObject);
}
in.close();
} else { result="9";}
return result;
} catch (MalformedURLException e) {
result="9";
} catch (IOException e) {
result="9";
}
catch (ParseException e) {
e.printStackTrace();
result="9";
}
finally {
urlConnection.disconnect();
}
return result;
When i input valid json data, all is OK, but if i got non json data, i got aplication crash with :
Caused by: java.lang.ClassCastException: java.lang.Long cannot be cast to org.json.simple.JSONObject
I think that
catch (ParseException e) {
e.printStackTrace();
result="9";
}
should handle this, but no.
So what i must do to avoid situation that aplication will crash when i do not get valid json?
The thrown exception is a ClassCastException. Maybe you can catch that exception also by adding another catch?
catch (ClassCastException e) {
e.printStackTrace();
result="9";
}
Try this to make a http request
class SendPostReqAsyncTask extends AsyncTask<String, Void, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(String... params) {
URL myUrl = null;
HttpURLConnection conn = null;
String response = "";
//String data = params[0];
try {
myUrl = new URL("http://www.example.com/json.json");
conn = (HttpURLConnection) myUrl.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
//one long string, first encode is the key to get the data on your web
//page, second encode is the value, keep concatenating key and value.
//theres another ways which easier then this long string in case you are
//posting a lot of info, look it up.
String postData = URLEncoder.encode("key", "UTF-8") + "=" +
URLEncoder.encode("value", "UTF-8");
OutputStream os = conn.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
bufferedWriter.write(postData);
bufferedWriter.flush();
bufferedWriter.close();
InputStream inputStream = conn.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
String line = "";
while ((line = bufferedReader.readLine()) != null) {
response += line;
}
bufferedReader.close();
inputStream.close();
conn.disconnect();
os.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
#Override
protected void onPostExecute(String s) {
try {
JSONObject jsonObject = new JSONObject(s);
} catch (JSONException e) {
//s may not be json
}
}
}
Before getting String from Json Object, check whether the Json object is not null and has that string. and then try to get it.
if (jsonObject!=null && jsonObject.has("name"))
{
result = jsonObject.get("name");
System.out.print(result);
}
I am passing the url https://www.reddit.com/r/wallpapers/top/.json into my method for getting the JSON array of a subreddit. However, it only returns the JSON array for the hot category rather than the top or new categories. I have checked the URL and code thoroughly and have tried other different formats of the URL to only get the same results. For some reason all JSON gets all return only the hot page or default subreddit URL. But when I visit the URL in my browser that I've linked, it displays the correct JSON array for the top category. (Android Studio)
Here's the beginning of my JSON task that returns the array:
private class JsonTask extends AsyncTask<String, String, String> {
protected void onPreExecute() {
super.onPreExecute();
}
protected String doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = null;
try {
stream = connection.getInputStream();
} catch (Exception e) {
Log.e("Subreddit Closed", urlString);
connection.disconnect();
return null; //if can't retrieve JSON file
}
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
}
return buffer.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
Update: This was an issue with Reddit's API, it is now working as expected. Take caution of URL formats as */hot/.json is equivalent to */.json
I'm trying to create an app for android and I'm trying to read my stats from my CloudFlare Dashboard.
The strange thing is that if my code reaches the line ins = con != null ? con.getInputStream() : null; It will say "FileNotFoundException".
The headers are set as they should. Here is the quote from the CF API Documentation:
The dashboard view provides both totals and timeseries data for the given zone and time period across the entire CloudFlare network.
GET /zones/:zone_identifier/analytics/dashboard
- https://api.cloudflare.com/#zone-analytics-dashboard
Some parameters are optional, I double checked my data already and it works fine in Postman.
I tried to use http but CF doesn't allow it.
My code:
class JsonRequest extends AsyncTask<String, String, String> {
private String readStream(InputStream is) {
try {
ByteArrayOutputStream bo = new ByteArrayOutputStream();
int i = is.read();
while (i != -1) {
bo.write(i);
i = is.read();
}
return bo.toString();
} catch (IOException e) {
return "";
}
}
protected String doInBackground(String... params) {
URL myurl = null;
try {
myurl = new URL(params[0]);
} catch (MalformedURLException e) {
e.printStackTrace();
}
HttpsURLConnection con = null;
try {
con = (HttpsURLConnection)myurl.openConnection();
con.setRequestProperty("X-Auth-Email", "email");
con.setRequestProperty("X-Auth-Key", "key");
con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
con.setRequestProperty("User-Agent","Mozilla/5.0 ( compatible ) ");
con.setRequestProperty("Accept","*/*");
con.setDoOutput(false);
} catch (IOException e) {
e.printStackTrace();
}
InputStream ins = null;
try {
ins = con != null ? con.getInputStream() : null; // FileNotFoundException
} catch (IOException e) {
e.printStackTrace();
}
InputStreamReader isr = new InputStreamReader(ins);
BufferedReader in = new BufferedReader(isr);
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
return readStream(ins);
}
}
I have a class audio sender which makes a connection to the nodejs server and uploads an audio file in POST method mode.
public class AudioSender implements Callable<JSONObject> {
String outputFile;
AudioSender(String fileLocation){
outputFile=fileLocation;
}
public JSONObject call(){
URL url = null;
HttpURLConnection urlConnection = null;
InputStream audioInputStream=null;
JSONObject response=null;
byte buffer[]=new byte[16];
try {
url = new URL("http://192.168.0.106:3000/upload");
} catch (MalformedURLException e) {
e.printStackTrace();
} finally {
try {
urlConnection = (HttpURLConnection) url.openConnection();
} catch (IOException e) {
e.printStackTrace();
} finally {
urlConnection.setDoOutput(true);
urlConnection.setChunkedStreamingMode(16);
urlConnection.setRequestProperty("Content-Type","multipart/form-data");
urlConnection.setRequestProperty("Connection", "Keep-Alive");
urlConnection.setRequestProperty("Cache-Control", "no-cache");
urlConnection.setRequestProperty(
"Content-Type", "multipart/form-data;boundary=*****");
try {
OutputStream out = new BufferedOutputStream(urlConnection.getOutputStream());
try {
audioInputStream = new BufferedInputStream(new FileInputStream(outputFile));
Log.d("hello","audioinputstream");
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
while(audioInputStream.read(buffer)!=-1) {
out.write(buffer);
Log.d("buffer",buffer.toString());
}
try {
audioInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
StringBuilder total = new StringBuilder();
while(in.read(buffer)!=-1)
total.append(buffer);
Log.d("response",total.toString());
try {
response = new JSONObject(total.toString());
}catch(JSONException e){
Log.e("Response Parse Error", "Could not parse malformed JSON");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
return response;
}
This is the upload that executes the AudioSender callable.
public void upload() {
JSONObject response=null;
AudioSender sender=new AudioSender(outputFile);
FutureTask<JSONObject> uploadTask=new FutureTask<JSONObject>(sender);
ExecutorService executorService= Executors.newFixedThreadPool(1);
executorService.execute(uploadTask);
Log.d("s","was here");
while(true){
if(uploadTask.isDone()){
try{
response=uploadTask.get();
}catch(InterruptedException|ExecutionException e){
e.printStackTrace();
Log.e("ee","ee",e.getCause());
}
}
}
}
I pretty much know this isn't node js's fault but here's the server code:
app.post('/upload',function(req,res){
console.log("someone called!");
req.on('data',function(chunk){
console.log('res');
console.log(chunk);
});
req.on('end',function(){
console.log("done!");
res.send({'name':'sg'});
});});
When I call upload(), the server console prints
someone called!
done!
I was debugging and found that indeed I am receiving the responded json object from the server. And I don't know if out.write(buffer) is doing the job, but debugging it shows that the buffer value is changing and is in par with my audio file's size.
Please do not suggest using ION or anything else.
I solved the problems by setting up the URLConnection as follows:
boundary = "===" + System.currentTimeMillis() + "===";
urlConnection.setUseCaches(false);
urlConnection.setDoOutput(true); // indicates POST method
urlConnection.setDoInput(true);
urlConnection.setRequestProperty("Content-Type","multipart/form-data; boundary=" + boundary);
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.