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Android HttpsURLConnection - simple POST request with parameters

I've been trying to get a simple android client server app working, and I've had nothing but trouble. I'm hoping someone can look at this code and see what I'm doing wrong, maybe I'm doing things in the wrong order, or forgetting something? Just adding the relevant parts
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.addRequestProperty("Content-Type", "application/json");
// set some made up parameters
String str = "{'login':'superman#super.com','password':'password'}";
byte[] outputInBytes = str.getBytes("UTF-8");
OutputStream os = conn.getOutputStream();
os.write( outputInBytes );
os.close();
// connection.setDoOutput(true); //should trigger POST - move above -> crash
conn.setRequestMethod("POST"); // explicitly set POST -move above so we can set params -> crash
conn.setDoInput(true);
The error I get is
'exception: java.net.ProtocolException: method does not support a
request body: GET'
If I just do a POST request without parameters it's fine, so I guess I should move the connection.setDoOutput(true); or conn.setRequestMethod("POST"); higher up, that should work right? When I do that I get the error:
exception: java.net.ProtocolException: Connection already established.
So, if I try to set to POST before adding parameters it doesn't work, if I try to do it after it doesn't work... what am I missing? Is there another way I should be doing this? Am I adding parameters incorrectly? I've been searching for a simple android networking example, and I can't find any, is there any example the official Android site? All I want to do is a very basic network operation, this is so frustrating!
EDIT: I need to use HttpsURLConnection for reasons not included in the above code- I need to authenticate, trust hosts, etc- so I'm really looking for a potential fix for the above code if possible.

Here is an example of how to post with a JSON Object:
JSONObject payload=new JSONObject();
try {
payload.put("password", params[1]);
payload.put("userName", params[0]);
} catch (JSONException e) {
e.printStackTrace();
}
String responseString="";
try
{
HttpPost httpPost = new HttpPost("www.theUrlYouQWant.com");
httpPost.setEntity(new StringEntity(payload.toString()));
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
HttpResponse response = new DefaultHttpClient().execute(httpPost);
responseString = EntityUtils.toString(response.getEntity());
}
catch (ClientProtocolException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
And example of how to get
String responseString = "";
//check if the username exists
StringBuilder builder = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet("www.theUrlYouQWant.com");
ArrayList<String> existingUserName = new ArrayList<String>();
try
{
HttpResponse response = client.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
}
else
{
Log.e(ParseException.class.toString(), "Failed to download file");
}
}
catch (ClientProtocolException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}

I followed this tutorial on making http calls:
http://www.androidhive.info/2012/01/android-json-parsing-tutorial/
Works fine with no problems.
Below is a class that I have modified from the sample:
public class ServiceHandler {
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
String TAG = ((Object) this).getClass().getSimpleName();
public ServiceHandler() {
}
/**
* Making service call
*
* #url - url to make request
* #method - http request method
*/
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/**
* Making service call
*
* #url - url to make request
* #method - http request method
* #params - http request params
*/
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
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 = 2000;
HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT)
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 2000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
Log.e("Request: ", "> " + url);
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
if (httpResponse != null) {
httpEntity = httpResponse.getEntity();
} else {
Log.e(TAG, "httpResponse is null");
}
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}
And this is how I use the class:
nameValuePairs = new ArrayList<NameValuePair>();
String param_value = "value";
String param_name = "name";
nameValuePairs.add(new BasicNameValuePair(param_name, param_value));
// Creating service handler class instance
sh = new ServiceHandler();
String json = sh.makeServiceCall(Utils.getUrl, ServiceHandler.GET, nameValuePairs);

Getting "Invalid JSON primitive" error while trying to get data from WebService

I'm working on an android app and I want to get some data from a WebService. I'm using this code to get JSON data from the WebService.
TextView textv=(TextView) findViewById(R.id.textv);
try {
HttpClient client = new DefaultHttpClient();
String URL = "http://server/WebService.asmx/Get_ActiveFair";
HttpPost post = new HttpPost(URL);
post.setHeader("Content-Type", "application/json; charset=utf-8");
HttpResponse responsePost = client.execute(post);
HttpEntity resEntityPost = responsePost.getEntity();
if (resEntityPost != null)
{
String response=EntityUtils.toString(resEntityPost);
Log.e("XXX",response);
textv.setText(response);
}
} catch (Exception e) {
e.printStackTrace();
textv.setText(e.toString());
Log.e("error!!",e.toString());
}
It works correctly an I get the data like this:
{
"d": "{\"Id\":2,\"Name\":\"Fair Name \",\"IsActive\":true,\"Date_Start\":\"\\/Date(1383343200000)\\/\",\"Date_End\":\"\\/Date(1384034400000)\\/\",\"Url_Map\":null,\"Details\":\"Fair Details \",\"Address\":\"FairAdress \",\"VisitingInfo\":\"Fair Visiting Info\",\"Contact\":null,\"Transportation\":\" Fair Transportation Info \"}"
}
But when I want to use another method in the webservice which needs to get FairId I get the result:
{
"Message": "Invalid JSON primitive: FairId.",
"StackTrace": " at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializePrimitiveObject()\r\n at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializeInternal(Int32 depth)\r\n at System.Web.Script.Serialization.JavaScriptObjectDeserializer.BasicDeserialize(String input, Int32 depthLimit, JavaScriptSerializer serializer)\r\n at System.Web.Script.Serialization.JavaScriptSerializer.Deserialize[T](String input)\r\n at System.Web.Script.Services.RestHandler.ExecuteWebServiceCall(HttpContext context, WebServiceMethodData methodData)",
"ExceptionType": "System.ArgumentException"
}
And here is my code to run the Get_EventList method:
TextView textv=(TextView) findViewById(R.id.textv);
try {
HttpClient client = new DefaultHttpClient();
String URL = "http://server/WebService.asmx/Get_EventList";
HttpPost post = new HttpPost(URL);
List<NameValuePair> postParameters;
postParameters = new ArrayList<NameValuePair>();
postParameters.add(new BasicNameValuePair("FairId", "2"));
post.setEntity(new UrlEncodedFormEntity(postParameters));
post.setHeader("Content-Type", "application/json; charset=utf-8");
HttpResponse responsePost = client.execute(post);
HttpEntity resEntityPost = responsePost.getEntity();
if (resEntityPost != null)
{
String response=EntityUtils.toString(resEntityPost);
Log.e("XXX",response);
textv.setText(response);
}
} catch (Exception e) {
e.printStackTrace();
textv.setText(e.toString());
Log.e("hata!!",e.toString());
}
What can be the problem? How can I solve it?

I solve the problem by sending FairId to WebService with JSONObject. Here is my new code:
TextView textv=(TextView) findViewById(R.id.textv);
try {
HttpClient client = new DefaultHttpClient();
String URL = "http://server/WebService.asmx/Get_EventList";
HttpPost post = new HttpPost(URL);
JSONObject json = new JSONObject();
json.put("FairId", "2");
StringEntity se = new StringEntity( json.toString());
se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
post.setEntity(se);
HttpResponse responsePost = client.execute(post);
HttpEntity resEntityPost = responsePost.getEntity();
if (resEntityPost != null)
{
String response=EntityUtils.toString(resEntityPost);
Log.e("XXX",response);
textv.setText(response);
}
} catch (Exception e) {
e.printStackTrace();
textv.setText(e.toString());
Log.e("hata!!",e.toString());
}

got exception when calling webservice in android?

I got two to three execption when calling webservice from android apps. When i call the webservice from apps on 2.3.3(Emulator) version then i got exception like UnhostException , connectiontimeoutexception on 4.2.1(real device) version and working fine on 3.1 version, i don't know why this happen. I was trying to solve this exception from yesterday but solved yet, if any changes needed in the code then please suggest me.
In LoginActivity I call the method for making the http request
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("tag", login_tag));
params.add(new BasicNameValuePair("email", username));
params.add(new BasicNameValuePair("password", userpsw));
JsonParserWebs jsonDataFromSrvr = new JsonParserWebs();
String loginData = jsonDataFromSrvr.makeHttpReqToSrvr(loginUrl,"POST", params);
Following is the JsonParserWebs for calling webservice
public String makeHttpReqToSrvr(String url,String requestType,List<NameValuePair> params) {
Log.i(JsonParserWebs.class.getName(),"URL..."+url);
HttpEntity httpEntity=null;
//making http request
try {
if (requestType == "GET") {
//connection time out
HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 5000);
HttpConnectionParams.setSoTimeout(httpParameters, 10000);
HttpClient httpClient = new DefaultHttpClient(httpParameters);
String paramString =URLEncodedUtils.format(params, "utf-8");
HttpGet httpGet = new HttpGet(url+"?"+paramString);
HttpResponse httpResp = httpClient.execute(httpGet);
httpEntity = httpResp.getEntity();
}
if (requestType == "POST") {
//connection time out
// From stackoverflow, I addes following three line but still got ConnectTimeoutException
HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 5000);
HttpConnectionParams.setSoTimeout(httpParameters, 10000);
HttpClient httpClient = new DefaultHttpClient(httpParameters);
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResp = httpClient.execute(httpPost);
httpEntity = httpResp.getEntity();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
json = EntityUtils.toString(httpEntity);
Log.v("JSON", "data"+json);
} catch (Exception e) {
e.printStackTrace();
}
// try parse the string to a JSON object
return json;
}
Thanks in Advance

You need to use AsyncTask , otherwise it will crash!

1. use AsyncTask when ever you use time consuming process other wise you will get network exception
2. take internet permission in .mainfeast

Access URL with Java

I am writing an Android program that needs to access a URL with GET variables which will be logged into a database. All I need to do is open a URL so the web server will log the data! How should I go about this?
Thanks

// default HTTP Client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

Use this.
Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("URL HERE"));
startActivity(browserIntent);
Hope this helps.
EDIT:
Ok, use this. It calls the URL without opening a browser
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpGet httpGet = new HttpGet("URL HERE");
HttpResponse response = httpClient.execute(httpGet, localContext);

You can also use HttpUrlConnection. Sample code -
// Given a URL, establishes an HttpUrlConnection and retrieves
// the web page content as a InputStream, which it returns as
// a string.
private String downloadUrl(String myurl) throws IOException {
InputStream is = null;
// Only display the first 500 characters of the retrieved
// web page content.
int len = 500;
try {
URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000 /* milliseconds */);
conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestMethod("GET");
conn.setDoInput(true);
// Starts the query
conn.connect();
int response = conn.getResponseCode();
Log.d(DEBUG_TAG, "The response is: " + response);
is = conn.getInputStream();
// Convert the InputStream into a string
String contentAsString = readIt(is, len);
return contentAsString;
// Makes sure that the InputStream is closed after the app is
// finished using it.
} finally {
if (is != null) {
is.close();
}
}
}
// Reads an InputStream and converts it to a String.
public String readIt(InputStream stream, int len) throws IOException, UnsupportedEncodingException {
Reader reader = null;
reader = new InputStreamReader(stream, "UTF-8");
char[] buffer = new char[len];
reader.read(buffer);
return new String(buffer);
}
And obviously since it is a netowork call you cannot do it in main/UI thread. So you can do it in async task. More details and Source

Android - Http Get Request

I'm trying to Get Request with code below but the stringbuilder is always null. The url is correct...
http://pastebin.com/mASvGmkq
EDIT
public static StringBuilder sendHttpGet(String url) {
HttpClient http = new DefaultHttpClient();
StringBuilder buffer = null;
try {
HttpGet get = new HttpGet(url);
HttpResponse resp = http.execute(get);
buffer = inputStreamToString(resp.getEntity().getContent());
}
catch(Exception e) {
debug("ERRO EM GET HTTP URL:\n" + url + "\n" + e);
return null;
}
debug("GET HTTP URL OK:\n" + buffer);
return buffer;
}

I usually do it like this:
try {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
output = EntityUtils.toString(httpEntity);
}
where output is a String-object.