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httpclient.execute(httpPost) error

In my android application I try to send a json object to a distant server, when I run it I get an error in httpclient.execute(httpPost)
This is a part of my code.
public static String GET(String url , JSONObject js){
try {
HttpPost httpPost = new HttpPost(url);
httpPost.addHeader("Authorization", "Basic **********");
httpPost.setEntity(new StringEntity(js.toString()));
HttpClient httpclient = new DefaultHttpClient();
httpclient.execute(httpPost);
} catch (Exception e) {
Log.i("Console", "Error");
}
Any help please.

I guess your Problem is, that you try to run your Network Request from your Main Thread.
I would discourage you to use the Apache HTTP Client at all.
It became deprecated for Marshmallow, see here
Maybe try OkHttp. It offers you the possibility to run a request asynchronously.

Sending something to a server - Updating android code

I would like to send a file to a server. Currently the code I use includes deprecated classes. How can I update the code to be uptodate?
protected String doInBackground(String... params) {
File file = new File(Environment.getExternalStorageDirectory().getAbsolutePath(), params[0]);
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(server);
InputStreamEntity reqEntity = new InputStreamEntity(new FileInputStream(file), -1);
reqEntity.setContentType("binary/octet-stream");
reqEntity.setChunked(true); // Send in multiple parts if needed
httppost.setEntity(reqEntity);
HttpResponse response = httpclient.execute(httppost);
//Do something with response...
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

I suggest you to use this library : retrofit
http://square.github.io/retrofit/
I use it on my project right now and it helps me a lot with my http requests.
Moreover the documentation is really good.

Android Java SQL Connect

So i'm a web developer by trade but am making an app at the moment.
I've got a program on my PC which sends data from my PC to a database on my webhost.
What I'm after now, is to create an app that is able to download that data with a series of queries.
Are there any good resources around that would help me to develop some Java code, to connect to a server through my tablet when I'm out and about and download the information from my webhost when on a different wifi network?
Thanks chaps, any help is appreciated.

The way I handle it is that I just create a web page based on what I want to do. For example if I want to verify a login on an app I create a page that takes in a username and password.
On the device I just post the username and password values by using a HTTP post transaction.
Example:
public boolean LoginUser()
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("your URL comes here...");
try
{
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
DataCrypt crypt = new DataCrypt();
try
{
this.Cryptemail = crypt.bytesToHex(crypt.encrypt(this.Email));;
this.Cryptpass = crypt.bytesToHex(crypt.encrypt(this.Password));
}
catch (Exception e)
{
DebugLog.log(e.getMessage());
}
nameValuePairs.add(new BasicNameValuePair("Password", this.Cryptpass));
nameValuePairs.add(new BasicNameValuePair("Mail", this.Cryptemail));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
BasicHttpResponse response = (BasicHttpResponse) httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
String response = EntityUtils.toString(entity);
return true;
}
catch (Exception e)
{
DebugLog.log(e.getMessage());
return false;
}
return false;
}
EDIT: So you can just make a page that takes in some parameters that you want to base your query on and return the result in some way (for example by XML).
Hope this helps you out! :)

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

I want to send the JSON text {} to a web service and read the response. How can I do this from android? What are the steps such as creating request object, setting content headers, etc.
My code is here
public void postData(String result,JSONObject obj) {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpParams myParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(myParams, 10000);
HttpConnectionParams.setSoTimeout(myParams, 10000);
String json=obj.toString();
try {
HttpPost httppost = new HttpPost(result.toString());
StringEntity se = new StringEntity(obj.toString());
se.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
httppost.setEntity(se);
HttpResponse response = httpclient.execute(httppost);
String temp = EntityUtils.toString(response.getEntity());
Log.i("tag", temp);
} catch (ClientProtocolException e) {
} catch (IOException e) {
}
}
what mistake i have done plz correct me because it shows me an bad request error
but when i do post in poster it shows me status as Successfull 200 ok

I do this with
httppost.setHeader("Content-type", "application/json");
Also, the new HttpPost() takes the web service URL as argument.

In the try catch loop, I did this:
HttpPost post = new HttpPost(
"https://www.placeyoururlhere.com");
post.setHeader(HTTP.CONTENT_TYPE,"application/json" );
List<NameValuePair> nameValuePairs = new
ArrayList<NameValuePair>(1);
nameValuePairs.add(new BasicNameValuePair("json", json));
post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpClient client = new DefaultHttpClient();
HttpResponse resp = client.execute(post);
HttpEntity entity = resp.getEntity();
response = EntityUtils.toString(entity);
You can add your nameValurPairs according to how many fields you have.
Typically the JSON might become really huge, which I will then suggest gzipping it then sending, but if your JSON is fairly small and always the same size the above should work for you.

If it is a web service and not RestAPI call then, you can get the WSDL file from the server and use a SOAP Stub generator to do all the work of creating the Request objects and the networking code for you, for example WSClient++
If you wish to do it by yourself then things get a little tricky. Android doesn't come with SOAP library.
However, you can download 3rd party library here: http://code.google.com/p/ksoap2-android/
If you need help using it, you might find this thread helpful: How to call a .NET Webservice from Android using KSOAP2?
If its a REST-API Call like POST or GET to be more specific then its is very simple
Just pass a JSON Formatted String object in you function and use org.json package to parse the response string for you.
Hope this helps.

etag comparision code example

I'm trying to simulate a process like "cache validation" in my application.
I will download a new version of my webapplication on the device (android-based), but I only want to download a new version of the files, based in a etag comparision.
Does anyone a example of how use the Etag mechanism in Android?

You can access the ETag field from a HttpURLConnection object such as like this:
HttpURLConnection conn = (HttpURLConnection)new URL(url).openConnection();
String etag = conn.getHeaderField("ETag");
Of course, you will need to make sure that the server you are testing this against supports ETags.

Maybe class "HttpRequest" from this library (kevinsawicki) will help you.
For example:
File latest = new File("/data/cache.json");
HttpRequest request = HttpRequest.get("http://google.com");
//Copy response to file
request.body(latest);
//Store eTag of response
String eTag = request.eTag();
//Later you can check if changes exist
boolean unchanged = HttpRequest.get("http://google.com")
.ifNoneMatch(eTag)
.notModified();

HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
try {
HttpResponse response = httpClient.execute(httpPost);
Log.d("Http Response:", response.getFirstHeader("etag").toString());
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

You can refer to the specific implement of ShallowEtagHeaderFilter performing etag generation and validation in Spring.