Rectangle 27 157

JSON stands for JavaScript Object Notation. In JavaScript properties can be referenced both like this object1.name and like this object['name'];. The example from the article uses this bit of JSON.

The Parts A fan object with email as a key and foo@bar.com as a value

{
  fan:
    {
      email : 'foo@bar.com'
    }
}

So the object equivalent would be fan.email; or fan['email'];. Both would have the same value of 'foo@bar.com'.

The following is what our author used to make a HttpClient Request. I do not claim to be an expert at all this so if anyone has a better way to word some of the terminology feel free.

public static HttpResponse makeRequest(String path, Map params) throws Exception 
{
    //instantiates httpclient to make request
    DefaultHttpClient httpclient = new DefaultHttpClient();

    //url with the post data
    HttpPost httpost = new HttpPost(path);

    //convert parameters into JSON object
    JSONObject holder = getJsonObjectFromMap(params);

    //passes the results to a string builder/entity
    StringEntity se = new StringEntity(holder.toString());

    //sets the post request as the resulting string
    httpost.setEntity(se);
    //sets a request header so the page receving the request
    //will know what to do with it
    httpost.setHeader("Accept", "application/json");
    httpost.setHeader("Content-type", "application/json");

    //Handles what is returned from the page 
    ResponseHandler responseHandler = new BasicResponseHandler();
    return httpclient.execute(httpost, responseHandler);
}

If you are not familiar with the Map data structure please take a look at the Java Map reference. In short, a map is similar to a dictionary or a hash.

private static JSONObject getJsonObjectFromMap(Map params) throws JSONException {

    //all the passed parameters from the post request
    //iterator used to loop through all the parameters
    //passed in the post request
    Iterator iter = params.entrySet().iterator();

    //Stores JSON
    JSONObject holder = new JSONObject();

    //using the earlier example your first entry would get email
    //and the inner while would get the value which would be 'foo@bar.com' 
    //{ fan: { email : 'foo@bar.com' } }

    //While there is another entry
    while (iter.hasNext()) 
    {
        //gets an entry in the params
        Map.Entry pairs = (Map.Entry)iter.next();

        //creates a key for Map
        String key = (String)pairs.getKey();

        //Create a new map
        Map m = (Map)pairs.getValue();   

        //object for storing Json
        JSONObject data = new JSONObject();

        //gets the value
        Iterator iter2 = m.entrySet().iterator();
        while (iter2.hasNext()) 
        {
            Map.Entry pairs2 = (Map.Entry)iter2.next();
            data.put((String)pairs2.getKey(), (String)pairs2.getValue());
        }

        //puts email and 'foo@bar.com'  together in map
        holder.put(key, data);
    }
    return holder;
}

Please feel free to comment on any questions that arise about this post or if I have not made something clear or if I have not touched on something that your still confused about... etc whatever pops in your head really.

(I will take down if Justin Grammens does not approve. But if not then thanks Justin for being cool about it.)

I just happend to get a comment about how to use the code and realized that there was a mistake in the return type. The method signature was set to return a string but in this case it wasnt returning anything. I changed the signature to HttpResponse and will refer you to this link on Getting Response Body of HttpResponse the path variable is the url and I updated to fix a mistake in the code.

Thanks @Terrance. So in a different class he is creating a map that has different keys and values that will later be turned into JSONObjects. I tried implementing something similar, but I have no experience with maps either, I'll add the code for what I tried implementing to my original post. Your explanations for what was going on made since, and I was successful in getting it to work by creating JSONObjects with hardcoded names and values. Thanks!

Justin says he approves. He should have enough rep to come and and leave a comment himself by now.

I want to use this code . How do I go about this ? Please specify what is the path variable and what has to be returned so that on my java end I can fetch the data.

getJsonObjectFromMap()
Map

How to send POST request in JSON using HTTPClient in Android? - Stack ...

android json post httprequest
Rectangle 27 32

I recommend using this HttpURLConnectioninstead HttpGet. As HttpGet is already deprecated in Android API level 22.

HttpURLConnection httpcon;  
String url = null;
String data = null;
String result = null;
try {
  //Connect
  httpcon = (HttpURLConnection) ((new URL (url).openConnection()));
  httpcon.setDoOutput(true);
  httpcon.setRequestProperty("Content-Type", "application/json");
  httpcon.setRequestProperty("Accept", "application/json");
  httpcon.setRequestMethod("POST");
  httpcon.connect();

  //Write       
  OutputStream os = httpcon.getOutputStream();
  BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
  writer.write(data);
  writer.close();
  os.close();

  //Read        
  BufferedReader br = new BufferedReader(new InputStreamReader(httpcon.getInputStream(),"UTF-8"));

  String line = null; 
  StringBuilder sb = new StringBuilder();         

  while ((line = br.readLine()) != null) {  
    sb.append(line); 
  }         

  br.close();  
  result = sb.toString();

} catch (UnsupportedEncodingException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}

How to send POST request in JSON using HTTPClient in Android? - Stack ...

android json post httprequest
Rectangle 27 41

Here is an alternative solution to @Terrance's answer. You can easly outsource the conversion. The Gson library does wonderful work converting various data structures into JSON and the other way around.

public static void execute() {
    Map<String, String> comment = new HashMap<String, String>();
    comment.put("subject", "Using the GSON library");
    comment.put("message", "Using libraries is convenient.");
    String json = new GsonBuilder().create().toJson(comment, Map.class);
    makeRequest("http://192.168.0.1:3000/post/77/comments", json);
}

public static HttpResponse makeRequest(String uri, String json) {
    try {
        HttpPost httpPost = new HttpPost(uri);
        httpPost.setEntity(new StringEntity(json));
        httpPost.setHeader("Accept", "application/json");
        httpPost.setHeader("Content-type", "application/json");
        return new DefaultHttpClient().execute(httpPost);
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

Similar can be done by using Jackson instead of Gson. I also recommend taking a look at Retrofit which hides a lot of this boilerplate code for you. For more experienced developers I recommend trying out RxAndroid.

my app is sending data via HttpPut method.when server got request, it reply as json data. I don't know how get data from json. please tell me. CODE.

@kongkea Please have a look into the GSON library. It is capable of parsing the JSON file into Java objects.

@JJD So far what you suggest is to send data to the remote server and its a nice explanation, but want to know how to parse the JSON object using HTTP protocol. Can u elaborate your answer with JSON parsing also. It will be very helpfull for everyone who is new in this.

@AndroidDev Please open a new question since this question is about sending data from the client to the server. Feel free to drop a link here.

@JJD you are calling abstract method execute() and it is failed of course

How to send POST request in JSON using HTTPClient in Android? - Stack ...

android json post httprequest
Rectangle 27 78

Sending a simple form

Sending a POST request is easy in vanilla Java. Starting with a URL, we need t convert it to a URLConnection using url.openConnection();. After that, we need to cast it to a HttpURLConnection, so we can access its setRequestMethod() method to set our method. We finally say that we are going to send data over the connection.

URL url = new URL("https://www.example.com/login");
URLConnection con = url.openConnection();
HttpURLConnection http = (HttpURLConnection)con;
http.setRequestMethod("POST"); // PUT is another valid option
http.setDoOutput(true);

A normal POST coming from a http form has a well defined format. We need to convert our input to this format:

Map<String,String> arguments = new HashMap<>();
arguments.put("username", "root");
arguments.put("password", "sjh76HSn!"); // This is a fake password obviously
StringJoiner sj = new StringJoiner("&");
for(Map.Entry<String,String> entry : arguments.entrySet())
    sj.add(URLEncoder.encode(entry.getKey(), "UTF-8") + "=" 
         + URLEncoder.encode(entry.getValue(), "UTF-8"));
byte[] out = sj.toString().getBytes(StandardCharsets.UTF_8);
int length = out.length;

We can then attach our form contents to the http request with proper headers and send it.

http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
    os.write(out);
}
// Do something with http.getInputStream()

We can also send json using java, this is also easy:

byte[] out = "{\"username\":\"root\",\"password\":\"password\"}" .getBytes(StandardCharsets.UTF_8);
int length = out.length;

http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
    os.write(out);
}
// Do something with http.getInputStream()

Sending files can be considered more challenging to handle as the format is more complex. We are also going to add support for sending the files as a string, since we don't want to buffer the file fully into the memory.

private void sendFile(OutputStream out, String name, InputStream in, String fileName) {
    String o = "Content-Disposition: form-data; name=\"" + URLEncoder.encode(name,"UTF-8") 
             + "\"; filename=\"" + URLEncoder.encode(filename,"UTF-8") + "\"\r\n\r\n";
    out.write(o.getBytes(StandardCharsets.UTF_8));
    byte[] buffer = new byte[2048];
    for (int n = 0; n >= 0; n = in.read(buffer))
        out.write(buffer, 0, n);
    out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}

private void sendField(OutputStream out, String name, String field) {
    String o = "Content-Disposition: form-data; name=\"" 
             + URLEncoder.encode(name,"UTF-8") + "\"\r\n\r\n";
    out.write(o.getBytes(StandardCharsets.UTF_8));
    out.write(URLEncoder.encode(field,"UTF-8").getBytes(StandardCharsets.UTF_8));
    out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}

We can then use these methods to create a multipart post request as follows:

String boundary = UUID.randomUUID().toString();
byte[] boundaryBytes = 
           ("--" + boundary + "\r\n").getBytes(StandardCharsets.UTF_8);
byte[] finishBoundaryBytes = 
           ("--" + boundary + "--").getBytes(StandardCharsets.UTF_8);
http.setRequestProperty("Content-Type", 
           "multipart/form-data; charset=UTF-8; boundary=" + boundary);

// Enable streaming mode with default settings
http.setChunkedStreamingMode(0); 

// Send our fields:
try(OutputStream out = http.getOutputStream()) {
    // Send our header (thx Algoman)
    out.write(boundaryBytes);

    // Send our first field
    sendField(out, "username", "root");

    // Send a seperator
    out.write(boundaryBytes);

    // Send our second field
    sendField(out, "password", "toor");

    // Send another seperator
    out.write(boundaryBytes);

    // Send our file
    try(InputStream file = new FileInputStream("test.txt")) {
        sendFile(out, "identification", file, "text.txt");
    }

    // Finish the request
    out.write(finishBoundaryBytes);
}


// Do something with http.getInputStream()

Nice answer Ferrybig. I like the spirit of giving so many angles on it.

This post is useful, but quite flawed. It took me 2 days to get it working. So to get it working you have to replace StandartCharsets.UTF8 with StandardCharsets.UTF_8 . boundaryBytes and finishBoundaryBytes need to get two additional hyphens which are NOT transmitted in the Content-Type, so boundaryBytes = ("--" + boundary + "\r\n").get... You also need to transmit the boundaryBytes once BEFORE the first field or the first field will be ignored!

out.write(finishBoundaryBytes);
http.connect();

Sending HTTP POST Request In Java - Stack Overflow

java http post
Rectangle 27 13

httppost.setHeader("Content-type", "application/json");

Also, the new HttpPost() takes the web service URL as argument.

How to send a JSON object over HttpClient Request with Android? - Stac...

android json post request
Rectangle 27 13

The Bad Request is the server saying that it doesn't like something in your POST.

The only obvious problem that I can see is that you're not telling the server that you're sending it JSON, so you may need to set a Content-Type header to indicate that the body is application/json:

postMethod.setHeader( "Content-Type", "application/json" );

If you don't have direct access to the server logs, then you need to liaise with the owner of the server to try and debug things. It could be that the format of your JSON is slightly wrong, there's a required field missing, or some other such problem.

If you can't get access use to the owner of the server, the you could try using a packet sniffer, such as WireShark, to capture packets both from your app, and from a successful POST and compare the two to try and work out what is different. This can be a little bit like finding a needle in a haystack though, particularly for large bodies.

If you can't get an example of a successful POST, then you're pretty well stuffed, as you have no point of reference.

sending json object to HTTP server in android - Stack Overflow

android json
Rectangle 27 13

SString otherParametersUrServiceNeed =  "Company=acompany&Lng=test&MainPeriod=test&UserID=123&CourseDate=8:10:10";
String request = "http://android.schoolportal.gr/Service.svc/SaveValues";

URL url = new URL(request); 
HttpURLConnection connection = (HttpURLConnection) url.openConnection();   
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setInstanceFollowRedirects(false); 
connection.setRequestMethod("POST"); 
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
connection.setRequestProperty("charset", "utf-8");
connection.setRequestProperty("Content-Length", "" + Integer.toString(otherParametersUrServiceNeed.getBytes().length));
connection.setUseCaches (false);

DataOutputStream wr = new DataOutputStream(connection.getOutputStream ());
wr.writeBytes(otherParametersUrServiceNeed);

   JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

wr.writeBytes(jsonParam.toString());

wr.flush();
wr.close();

well i did that but i still get a bad request as a server response.Now let me ask if i did everything corect :When i set the otherparameter should i put param1 or the name of my parameters?also,my json object is the first parameter so first i write this one and after that i write the otherparameters is that right?

On server side the param sequence does not matter.It seems you are puting json in payload ... in this otherParametersUrServiceNeed = "param1=a&param2=b&param3=c"; put the name of parameters that you server need this is just example ..You should first identify the parameters that you server need in request the add these params and there values in String otherParametersUrService as my example demonstrates.

If it is not confidential you can tell me what addition params your server need ..so that i can put them in above example .

Well it's not,it is okay if i give you the method signature??:long InsertStudentAbsences(SRV_Students_Absence objStudentAbsences, string Company, string Lng, string MainPeriod, string UserID, string CourseDate);

java - Sending a JSON HTTP POST request from Android - Stack Overflow

java android json wcf httpurlconnection
Rectangle 27 13

SString otherParametersUrServiceNeed =  "Company=acompany&Lng=test&MainPeriod=test&UserID=123&CourseDate=8:10:10";
String request = "http://android.schoolportal.gr/Service.svc/SaveValues";

URL url = new URL(request); 
HttpURLConnection connection = (HttpURLConnection) url.openConnection();   
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setInstanceFollowRedirects(false); 
connection.setRequestMethod("POST"); 
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
connection.setRequestProperty("charset", "utf-8");
connection.setRequestProperty("Content-Length", "" + Integer.toString(otherParametersUrServiceNeed.getBytes().length));
connection.setUseCaches (false);

DataOutputStream wr = new DataOutputStream(connection.getOutputStream ());
wr.writeBytes(otherParametersUrServiceNeed);

   JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

wr.writeBytes(jsonParam.toString());

wr.flush();
wr.close();

well i did that but i still get a bad request as a server response.Now let me ask if i did everything corect :When i set the otherparameter should i put param1 or the name of my parameters?also,my json object is the first parameter so first i write this one and after that i write the otherparameters is that right?

On server side the param sequence does not matter.It seems you are puting json in payload ... in this otherParametersUrServiceNeed = "param1=a&param2=b&param3=c"; put the name of parameters that you server need this is just example ..You should first identify the parameters that you server need in request the add these params and there values in String otherParametersUrService as my example demonstrates.

If it is not confidential you can tell me what addition params your server need ..so that i can put them in above example .

Well it's not,it is okay if i give you the method signature??:long InsertStudentAbsences(SRV_Students_Absence objStudentAbsences, string Company, string Lng, string MainPeriod, string UserID, string CourseDate);

java - Sending a JSON HTTP POST request from Android - Stack Overflow

java android json wcf httpurlconnection
Rectangle 27 3

public String makePOSTRequest(String url, List<NameValuePair> nameValuePairs) {
    String response = "";

    try {
        HttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);
        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        response = EntityUtils.toString(httpEntity);
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    Log.d(LOGTAG, "POST Response >>> " + response);
    return response;

}
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("json",jsonObject.toString()));

String response = makePOSTRequest(String url, nameValuePairs );
$jsonInput = $_POST['json'];
json_decode($jsonInput);

Thanks, works like a charm! :) Can you explain what's going on and what I did wrong?

php - sending JSON to server using POST in android app - Stack Overflo...

php android json curl
Rectangle 27 10

Sorry folks, just turned out that the error was on the Rest service. I have change it to receive a String instead of the Reader object and now it works as expected, the Rest code on the server side now is:

@POST
@Path("/cadastrar/{userEmail}")
@Consumes(MediaType.APPLICATION_JSON)
public String cadastraPeso(@PathParam("userEmail") String email, String jsonString)
{
        String json = jsonString;
        if(json != null)
        {
            log.debug("String json recebida do device ==>> " + json);
        }   
        return "OK - o e-mail processado foi ==>> " + email;
}

And the JSon string is correctly receive in server side.

So de Android code above it's working as expected.

Hi Arthur, I have to tell you I am still a bit lost using stack overflow. As a starter it looks too much information for me, I mean, all the mecanics on this points, comments, posts, as a first impression looks a bit confuse these forums, but I have found great information using it so I hope to get used quick.

I'm glad you find this site useful, but please accept your own answer as an accepted answer by clicking the icon below the down arrow. It will be highlighted as green when your mouse is over it.

@Shervin It looks like I have to wait a couple of days to be able to do that. Ill do it than.

How do I send JSon as BODY In a POST request to server from an Android...

android json rest post seam
Rectangle 27 5

Too much code for this task, checkout this library https://github.com/kodart/Httpzoid Is uses GSON internally and provides API that works with objects. All JSON details are hidden.

Http http = HttpFactory.create(context);
http.get("http://example.com/users")
    .handler(new ResponseHandler<User[]>() {
        @Override
        public void success(User[] users, HttpResponse response) {
        }
    }).execute();

great solution, unfortunately this plugin lacks gradle support :/

How to send POST request in JSON using HTTPClient in Android? - Stack ...

android json post httprequest
Rectangle 27 54

URL url;
URLConnection urlConn;
DataOutputStream printout;
DataInputStream  input;
url = new URL (getCodeBase().toString() + "env.tcgi");
urlConn = url.openConnection();
urlConn.setDoInput (true);
urlConn.setDoOutput (true);
urlConn.setUseCaches (false);
urlConn.setRequestProperty("Content-Type","application/json");   
urlConn.setRequestProperty("Host", "android.schoolportal.gr");
urlConn.connect();  
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

The part which you missed is in the the following... i.e., as follows..

// Send POST output.
printout = new DataOutputStream(urlConn.getOutputStream ());
printout.writeBytes(URLEncoder.encode(jsonParam.toString(),"UTF-8"));
printout.flush ();
printout.close ();

The rest of the thing you can do it.

The method write(int) in the type DataOutputStream is not applicable for the arguments (String)

Instead of write(int); I used String str = jsonString.toString(); byte[] data=str.getBytes("UTF-8"); printout.write(data); printout.flush (); printout.close (); It is working.

It's an old answer, but it worked great for me to move away from the deprecated DefaultHttpClient. I also moved from the deprecated NameValuePair to a JSON Object. BTW,I had to change the "write" to "writeBytes".

I was getting the error explained above, wrong parameter types for printout.write(), so I used printout.writeUTF(URLEncoder.encode(params.toString(), "UTF-8"));

java - Sending a JSON HTTP POST request from Android - Stack Overflow

java android json wcf httpurlconnection
Rectangle 27 3

There are couple of ways to establish HHTP connection and fetch data from a RESTFULL web service. The most recent one is GSON. But before you proceed to GSON you must have some idea of the most traditional way of creating an HTTP Client and perform data communication with a remote server. I have mentioned both the methods to send POST & GET requests using HTTPClient.

/**
 * This method is used to process GET requests to the server.
 * 
 * @param url 
 * @return String
 * @throws IOException
 */
public static String connect(String url) throws IOException {

    HttpGet httpget = new HttpGet(url);
    HttpResponse response;
    HttpParams httpParameters = new BasicHttpParams();
    // Set the timeout in milliseconds until a connection is established.
    // The default value is zero, that means the timeout is not used. 
    int timeoutConnection = 60*1000;
    HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
    // Set the default socket timeout (SO_TIMEOUT) 
    // in milliseconds which is the timeout for waiting for data.
    int timeoutSocket = 60*1000;

    HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
    HttpClient httpclient = new DefaultHttpClient(httpParameters);
    try {

        response = httpclient.execute(httpget);

        HttpEntity entity = response.getEntity();
        if (entity != null) {
            InputStream instream = entity.getContent();
            result = convertStreamToString(instream);
            //instream.close();
        }
    } 
    catch (ClientProtocolException e) {
        Utilities.showDLog("connect","ClientProtocolException:-"+e);
    } catch (IOException e) {
        Utilities.showDLog("connect","IOException:-"+e); 
    }
    return result;
}


 /**
 * This method is used to send POST requests to the server.
 * 
 * @param URL
 * @param paramenter
 * @return result of server response
 */
static public String postHTPPRequest(String URL, String paramenter) {       

    HttpParams httpParameters = new BasicHttpParams();
    // Set the timeout in milliseconds until a connection is established.
    // The default value is zero, that means the timeout is not used. 
    int timeoutConnection = 60*1000;
    HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
    // Set the default socket timeout (SO_TIMEOUT) 
    // in milliseconds which is the timeout for waiting for data.
    int timeoutSocket = 60*1000;

    HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
    HttpClient httpclient = new DefaultHttpClient(httpParameters);
    HttpPost httppost = new HttpPost(URL);
    httppost.setHeader("Content-Type", "application/json");
    try {
        if (paramenter != null) {
            StringEntity tmp = null;
            tmp = new StringEntity(paramenter, "UTF-8");
            httppost.setEntity(tmp);
        }
        HttpResponse httpResponse = null;
        httpResponse = httpclient.execute(httppost);
        HttpEntity entity = httpResponse.getEntity();
        if (entity != null) {
            InputStream input = null;
            input = entity.getContent();
            String res = convertStreamToString(input);
            return res;
        }
    } 
     catch (Exception e) {
        System.out.print(e.toString());
    }
    return null;
}

How to send POST request in JSON using HTTPClient in Android? - Stack ...

android json post httprequest
Rectangle 27 12

You can use this code for connect and request using http and json

try {

        URL url = new URL("https://www.googleapis.com/youtube/v3/playlistItems?part=snippet"
                + "&key=AIzaSyAhONZJpMCBqCfQjFUj21cR2klf6JWbVSo"
                + "&access_token=" + access_token);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setDoOutput(true);
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type", "application/json");

        String input = "{ \"snippet\": {\"playlistId\": \"WL\",\"resourceId\": {\"videoId\": \""+videoId+"\",\"kind\": \"youtube#video\"},\"position\": 0}}";

        OutputStream os = conn.getOutputStream();
        os.write(input.getBytes());
        os.flush();

        if (conn.getResponseCode() != HttpURLConnection.HTTP_CREATED) {
            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();

     }

if you see an error add this but this is not a good job.

if (Build.VERSION.SDK_INT >= 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }

POST request send json data java HttpUrlConnection - Stack Overflow

java json post curl httpurlconnection
Rectangle 27 94

<?php
// Your ID and token
$blogID = '8070105920543249955';
$authToken = 'OAuth 2.0 token here';

// The data to send to the API
$postData = array(
    'kind' => 'blogger#post',
    'blog' => array('id' => $blogID),
    'title' => 'A new post',
    'content' => 'With <b>exciting</b> content...'
);

// Create the context for the request
$context = stream_context_create(array(
    'http' => array(
        // http://www.php.net/manual/en/context.http.php
        'method' => 'POST',
        'header' => "Authorization: {$authToken}\r\n".
            "Content-Type: application/json\r\n",
        'content' => json_encode($postData)
    )
));

// Send the request
$response = file_get_contents('https://www.googleapis.com/blogger/v3/blogs/'.$blogID.'/posts/', FALSE, $context);

// Check for errors
if($response === FALSE){
    die('Error');
}

// Decode the response
$responseData = json_decode($response, TRUE);

// Print the date from the response
echo $responseData['published'];

Great tutorial! Even the json part is included :-)

// Send the request $response = file_get_contents('https://www.googleapis.com/blogger/v3/blogs/'.$blogID.'/posts/', FALSE, $context);

@Matt: Does the cURL example (first one) work? Your webhost/PHP installation could be blocking file_get_contents. Is there anymore to the error besides that?

I noticed that authorization header must constructed like this: Authorization: OAuth {$authToken}.

php - POST request with JSON body - Stack Overflow

php json post
Rectangle 27 52

URL url;
URLConnection urlConn;
DataOutputStream printout;
DataInputStream  input;
url = new URL (getCodeBase().toString() + "env.tcgi");
urlConn = url.openConnection();
urlConn.setDoInput (true);
urlConn.setDoOutput (true);
urlConn.setUseCaches (false);
urlConn.setRequestProperty("Content-Type","application/json");   
urlConn.setRequestProperty("Host", "android.schoolportal.gr");
urlConn.connect();  
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

The part which you missed is in the the following... i.e., as follows..

// Send POST output.
printout = new DataOutputStream(urlConn.getOutputStream ());
printout.writeBytes(URLEncoder.encode(jsonParam.toString(),"UTF-8"));
printout.flush ();
printout.close ();

The rest of the thing you can do it.

The method write(int) in the type DataOutputStream is not applicable for the arguments (String)

Instead of write(int); I used String str = jsonString.toString(); byte[] data=str.getBytes("UTF-8"); printout.write(data); printout.flush (); printout.close (); It is working.

It's an old answer, but it worked great for me to move away from the deprecated DefaultHttpClient. I also moved from the deprecated NameValuePair to a JSON Object. BTW,I had to change the "write" to "writeBytes".

I was getting the error explained above, wrong parameter types for printout.write(), so I used printout.writeUTF(URLEncoder.encode(params.toString(), "UTF-8"));

java - Sending a JSON HTTP POST request from Android - Stack Overflow

java android json wcf httpurlconnection
Rectangle 27 33

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class HttpLogin extends Activity {
    /** Called when the activity is first created. */
    private Button login;
    private EditText username, password;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        login = (Button) findViewById(R.id.login);
        username = (EditText) findViewById(R.id.username);
        password = (EditText) findViewById(R.id.password);

        login.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                String   mUsername = username.getText().toString();
                String  mPassword = password.getText().toString();

                tryLogin(mUsername, mPassword);
            }
        });
    }

    protected void tryLogin(String mUsername, String mPassword)
    {           
        HttpURLConnection connection;
       OutputStreamWriter request = null;

            URL url = null;   
            String response = null;         
            String parameters = "username="+mUsername+"&password="+mPassword;   

            try
            {
                url = new URL("your login URL");
                connection = (HttpURLConnection) url.openConnection();
                connection.setDoOutput(true);
                connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
                connection.setRequestMethod("POST");    

                request = new OutputStreamWriter(connection.getOutputStream());
                request.write(parameters);
                request.flush();
                request.close();            
                String line = "";               
                InputStreamReader isr = new InputStreamReader(connection.getInputStream());
                BufferedReader reader = new BufferedReader(isr);
                StringBuilder sb = new StringBuilder();
                while ((line = reader.readLine()) != null)
                {
                    sb.append(line + "\n");
                }
                // Response from server after login process will be stored in response variable.                
                response = sb.toString();
                // You can perform UI operations here
                Toast.makeText(this,"Message from Server: \n"+ response, 0).show();             
                isr.close();
                reader.close();

            }
            catch(IOException e)
            {
                // Error
            }
    }
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
  >
<EditText android:hint="Username" android:id="@+id/username" android:layout_width="fill_parent" android:layout_height="wrap_content"></EditText>
<EditText android:hint="Password" android:id="@+id/password" android:layout_width="fill_parent" android:layout_height="wrap_content" android:inputType="textPassword"></EditText>
<Button android:text="Sign In" android:id="@+id/login" android:layout_width="fill_parent" android:layout_height="wrap_content"></Button>
</LinearLayout>

but how will i get value from the textbox and so on? how can i do the new screen show??

String parameters = "username="+txtUserName.getText().toString()+"&password"=txtPassword.getText().toString(); Here txtUserName and txtPassword are the EditText fields

thks vikas...where will i get the response?? and where should i place a screen changing code??

Sending passwords in plain text over the network is a very bad idea.

@ Octavian Damiean: Off course it's a bad idea. But remember it's not a primary intention of this question, simply it is showing how to do a http post.

How to do a HTTP Post in Android? - Stack Overflow

android http http-post
Rectangle 27 12

You can use this code for connect and request using http and json

try {

        URL url = new URL("https://www.googleapis.com/youtube/v3/playlistItems?part=snippet"
                + "&key=AIzaSyAhONZJpMCBqCfQjFUj21cR2klf6JWbVSo"
                + "&access_token=" + access_token);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setDoOutput(true);
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type", "application/json");

        String input = "{ \"snippet\": {\"playlistId\": \"WL\",\"resourceId\": {\"videoId\": \""+videoId+"\",\"kind\": \"youtube#video\"},\"position\": 0}}";

        OutputStream os = conn.getOutputStream();
        os.write(input.getBytes());
        os.flush();

        if (conn.getResponseCode() != HttpURLConnection.HTTP_CREATED) {
            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();

     }

if you see an error add this but this is not a good job.

if (Build.VERSION.SDK_INT >= 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }

POST request send json data java HttpUrlConnection - Stack Overflow

java json post curl httpurlconnection
Rectangle 27 43

By this way we can send data with http post method and get result

public class MyHttpPostProjectActivity extends Activity implements OnClickListener {

    private EditText usernameEditText;
    private EditText passwordEditText;
    private Button sendPostReqButton;
    private Button clearButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        usernameEditText = (EditText) findViewById(R.id.login_username_editText);
        passwordEditText = (EditText) findViewById(R.id.login_password_editText);

        sendPostReqButton = (Button) findViewById(R.id.login_sendPostReq_button);
        sendPostReqButton.setOnClickListener(this);

        clearButton = (Button) findViewById(R.id.login_clear_button);
        clearButton.setOnClickListener(this);        
    }

    @Override
    public void onClick(View v) {

        if(v.getId() == R.id.login_clear_button){
            usernameEditText.setText("");
            passwordEditText.setText("");
            passwordEditText.setCursorVisible(false);
            passwordEditText.setFocusable(false);
            usernameEditText.setCursorVisible(true);
            passwordEditText.setFocusable(true);
        }else if(v.getId() == R.id.login_sendPostReq_button){
            String givenUsername = usernameEditText.getEditableText().toString();
            String givenPassword = passwordEditText.getEditableText().toString();

            System.out.println("Given username :" + givenUsername + " Given password :" + givenPassword);

            sendPostRequest(givenUsername, givenPassword);
        }   
    }

    private void sendPostRequest(String givenUsername, String givenPassword) {

        class SendPostReqAsyncTask extends AsyncTask<String, Void, String>{

            @Override
            protected String doInBackground(String... params) {

                String paramUsername = params[0];
                String paramPassword = params[1];

                System.out.println("*** doInBackground ** paramUsername " + paramUsername + " paramPassword :" + paramPassword);

                HttpClient httpClient = new DefaultHttpClient();

                // In a POST request, we don't pass the values in the URL.
                //Therefore we use only the web page URL as the parameter of the HttpPost argument
                HttpPost httpPost = new HttpPost("http://www.nirmana.lk/hec/android/postLogin.php");

                // Because we are not passing values over the URL, we should have a mechanism to pass the values that can be
                //uniquely separate by the other end.
                //To achieve that we use BasicNameValuePair             
                //Things we need to pass with the POST request
                BasicNameValuePair usernameBasicNameValuePair = new BasicNameValuePair("paramUsername", paramUsername);
                BasicNameValuePair passwordBasicNameValuePAir = new BasicNameValuePair("paramPassword", paramPassword);

                // We add the content that we want to pass with the POST request to as name-value pairs
                //Now we put those sending details to an ArrayList with type safe of NameValuePair
                List<NameValuePair> nameValuePairList = new ArrayList<NameValuePair>();
                nameValuePairList.add(usernameBasicNameValuePair);
                nameValuePairList.add(passwordBasicNameValuePAir);

                try {
                    // UrlEncodedFormEntity is an entity composed of a list of url-encoded pairs. 
                    //This is typically useful while sending an HTTP POST request. 
                    UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairList);

                    // setEntity() hands the entity (here it is urlEncodedFormEntity) to the request.
                    httpPost.setEntity(urlEncodedFormEntity);

                    try {
                        // HttpResponse is an interface just like HttpPost.
                        //Therefore we can't initialize them
                        HttpResponse httpResponse = httpClient.execute(httpPost);

                        // According to the JAVA API, InputStream constructor do nothing. 
                        //So we can't initialize InputStream although it is not an interface
                        InputStream inputStream = httpResponse.getEntity().getContent();

                        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);

                        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

                        StringBuilder stringBuilder = new StringBuilder();

                        String bufferedStrChunk = null;

                        while((bufferedStrChunk = bufferedReader.readLine()) != null){
                            stringBuilder.append(bufferedStrChunk);
                        }

                        return stringBuilder.toString();

                    } catch (ClientProtocolException cpe) {
                        System.out.println("First Exception caz of HttpResponese :" + cpe);
                        cpe.printStackTrace();
                    } catch (IOException ioe) {
                        System.out.println("Second Exception caz of HttpResponse :" + ioe);
                        ioe.printStackTrace();
                    }

                } catch (UnsupportedEncodingException uee) {
                    System.out.println("An Exception given because of UrlEncodedFormEntity argument :" + uee);
                    uee.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(String result) {
                super.onPostExecute(result);

                if(result.equals("working")){
                    Toast.makeText(getApplicationContext(), "HTTP POST is working...", Toast.LENGTH_LONG).show();
                }else{
                    Toast.makeText(getApplicationContext(), "Invalid POST req...", Toast.LENGTH_LONG).show();
                }
            }           
        }

        SendPostReqAsyncTask sendPostReqAsyncTask = new SendPostReqAsyncTask();
        sendPostReqAsyncTask.execute(givenUsername, givenPassword);     
    }
}

you are a lifesaver, ty

java - Sending POST data in Android - Stack Overflow

java php android client-server httpconnection
Rectangle 27 43

By this way we can send data with http post method and get result

public class MyHttpPostProjectActivity extends Activity implements OnClickListener {

    private EditText usernameEditText;
    private EditText passwordEditText;
    private Button sendPostReqButton;
    private Button clearButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        usernameEditText = (EditText) findViewById(R.id.login_username_editText);
        passwordEditText = (EditText) findViewById(R.id.login_password_editText);

        sendPostReqButton = (Button) findViewById(R.id.login_sendPostReq_button);
        sendPostReqButton.setOnClickListener(this);

        clearButton = (Button) findViewById(R.id.login_clear_button);
        clearButton.setOnClickListener(this);        
    }

    @Override
    public void onClick(View v) {

        if(v.getId() == R.id.login_clear_button){
            usernameEditText.setText("");
            passwordEditText.setText("");
            passwordEditText.setCursorVisible(false);
            passwordEditText.setFocusable(false);
            usernameEditText.setCursorVisible(true);
            passwordEditText.setFocusable(true);
        }else if(v.getId() == R.id.login_sendPostReq_button){
            String givenUsername = usernameEditText.getEditableText().toString();
            String givenPassword = passwordEditText.getEditableText().toString();

            System.out.println("Given username :" + givenUsername + " Given password :" + givenPassword);

            sendPostRequest(givenUsername, givenPassword);
        }   
    }

    private void sendPostRequest(String givenUsername, String givenPassword) {

        class SendPostReqAsyncTask extends AsyncTask<String, Void, String>{

            @Override
            protected String doInBackground(String... params) {

                String paramUsername = params[0];
                String paramPassword = params[1];

                System.out.println("*** doInBackground ** paramUsername " + paramUsername + " paramPassword :" + paramPassword);

                HttpClient httpClient = new DefaultHttpClient();

                // In a POST request, we don't pass the values in the URL.
                //Therefore we use only the web page URL as the parameter of the HttpPost argument
                HttpPost httpPost = new HttpPost("http://www.nirmana.lk/hec/android/postLogin.php");

                // Because we are not passing values over the URL, we should have a mechanism to pass the values that can be
                //uniquely separate by the other end.
                //To achieve that we use BasicNameValuePair             
                //Things we need to pass with the POST request
                BasicNameValuePair usernameBasicNameValuePair = new BasicNameValuePair("paramUsername", paramUsername);
                BasicNameValuePair passwordBasicNameValuePAir = new BasicNameValuePair("paramPassword", paramPassword);

                // We add the content that we want to pass with the POST request to as name-value pairs
                //Now we put those sending details to an ArrayList with type safe of NameValuePair
                List<NameValuePair> nameValuePairList = new ArrayList<NameValuePair>();
                nameValuePairList.add(usernameBasicNameValuePair);
                nameValuePairList.add(passwordBasicNameValuePAir);

                try {
                    // UrlEncodedFormEntity is an entity composed of a list of url-encoded pairs. 
                    //This is typically useful while sending an HTTP POST request. 
                    UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairList);

                    // setEntity() hands the entity (here it is urlEncodedFormEntity) to the request.
                    httpPost.setEntity(urlEncodedFormEntity);

                    try {
                        // HttpResponse is an interface just like HttpPost.
                        //Therefore we can't initialize them
                        HttpResponse httpResponse = httpClient.execute(httpPost);

                        // According to the JAVA API, InputStream constructor do nothing. 
                        //So we can't initialize InputStream although it is not an interface
                        InputStream inputStream = httpResponse.getEntity().getContent();

                        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);

                        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

                        StringBuilder stringBuilder = new StringBuilder();

                        String bufferedStrChunk = null;

                        while((bufferedStrChunk = bufferedReader.readLine()) != null){
                            stringBuilder.append(bufferedStrChunk);
                        }

                        return stringBuilder.toString();

                    } catch (ClientProtocolException cpe) {
                        System.out.println("First Exception caz of HttpResponese :" + cpe);
                        cpe.printStackTrace();
                    } catch (IOException ioe) {
                        System.out.println("Second Exception caz of HttpResponse :" + ioe);
                        ioe.printStackTrace();
                    }

                } catch (UnsupportedEncodingException uee) {
                    System.out.println("An Exception given because of UrlEncodedFormEntity argument :" + uee);
                    uee.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(String result) {
                super.onPostExecute(result);

                if(result.equals("working")){
                    Toast.makeText(getApplicationContext(), "HTTP POST is working...", Toast.LENGTH_LONG).show();
                }else{
                    Toast.makeText(getApplicationContext(), "Invalid POST req...", Toast.LENGTH_LONG).show();
                }
            }           
        }

        SendPostReqAsyncTask sendPostReqAsyncTask = new SendPostReqAsyncTask();
        sendPostReqAsyncTask.execute(givenUsername, givenPassword);     
    }
}

java - Sending POST data in Android - Stack Overflow

java php android client-server httpconnection