Develop Reference

Can I send a Android HttpGet (not HttpPost) with 1 string param?

Im coding a RESTful API & Android client at the same time as I go and im currently working on pulling the users profile from the server. I feel like this should definitely be a get request being that im only pulling existing data and im not adding/editing anything to my database, but I do need a user_id param to be able to query for the appropriate profile. Can I send just one tiny little variable along with my HttpGet some how or am i supposed to use a HttpPost in this situation regardless?

Android uses Apache's HTTPClient. So, copying their tutorial code:
public void sendStringTo(String remoteUrl, String myString) {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(remoteUrl+"?string1="+myString);
HttpResponse response1 = httpclient.execute(httpGet);
// The underlying HTTP connection is still held by the response object
// to allow the response content to be streamed directly from the network socket.
// In order to ensure correct deallocation of system resources
// the user MUST either fully consume the response content or abort request
// execution by calling HttpGet#releaseConnection().
try {
System.out.println(response1.getStatusLine());
HttpEntity entity1 = response1.getEntity();
// do something useful with the response body
// and ensure it is fully consumed
EntityUtils.consume(entity1);
} finally {
httpGet.releaseConnection();
}
return;
}

GET can support adding variables/parameters. For example you could make a Url that looks like this:
http://yourwebsite.com/script.php?user_id=19898424

Http Put Request

I am using the HttpPut to communicate with server in Android, the response code I am getting is 500.After talking with the server guy he said prepare the string like below and send.
{"key":"value","key":"value"}
now I am completely confused that where should i add this string in my request.
Please help me out .

I recently had to figure out a way to get my android app to communicate with a WCF service and update a particular record. At first this was really giving me a hard time figuring it out, mainly due to me not knowing enough about HTTP protocols, but I was able to create a PUT by using the following:
URL url = new URL("http://(...your service...).svc/(...your table name...)(...ID of record trying to update...)");
//--This code works for updating a record from the feed--
HttpPut httpPut = new HttpPut(url.toString());
JSONStringer json = new JSONStringer()
.object()
.key("your tables column name...").value("...updated value...")
.endObject();
StringEntity entity = new StringEntity(json.toString());
entity.setContentType("application/json;charset=UTF-8");//text/plain;charset=UTF-8
entity.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE,"application/json;charset=UTF-8"));
httpPut.setEntity(entity);
// Send request to WCF service
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(httpPut);
HttpEntity entity1 = response.getEntity();
if(entity1 != null&&(response.getStatusLine().getStatusCode()==201||response.getStatusLine().getStatusCode()==200))
{
//--just so that you can view the response, this is optional--
int sc = response.getStatusLine().getStatusCode();
String sl = response.getStatusLine().getReasonPhrase();
}
else
{
int sc = response.getStatusLine().getStatusCode();
String sl = response.getStatusLine().getReasonPhrase();
}
With this being said there is an easier option by using a library that will generate the update methods for you to allow for you to update a record without having to manually write the code like I did above. The 2 libraries that seem to be common are odata4j and restlet. Although I haven't been able to find a clear easy tutorial for odata4j there is one for restlet that is really nice: http://weblogs.asp.net/uruit/archive/2011/09/13/accessing-odata-from-android-using-restlet.aspx?CommentPosted=true#commentmessage

Error 500 is Internal Server error. Not sure if this answers your question but I personally encountered it when trying to send a data URI for an animated gif in a PUT request formatted in JSON but the data URI was too long. You may be sending too much information at once.

Android uploading file as ByteArray to WCF REST services

I need to send a byte arrray file using WCF rest services. I have to send the data using HttpPost method in android. The code which i am using give the status as HTTP/1.1 400 Bad Request error.
private final static String URI = "http://192.168.1.15/QueryService/Import/Test";
final HttpPost request = new HttpPost(URI);
final HttpClient httpClient = new DefaultHttpClient();
final ByteArrayEntity entity = new ByteArrayEntity(fileToBytes(pathToOurFile));
entity.setContentType("application/octet-stream");
entity.setChunked(true);
request.setEntity(entity);
final HttpResponse hr = httpClient.execute(request);
final StatusLine status = hr.getStatusLine();
httpClient.getConnectionManager().shutdown();

It is difficult to tell what is wrong with your request. The standard way of resolving this kind of errors is:
Create a WCF client for your service. Verify that it works as expected.
Use Fiddler or another suitable tool to intercept the HTTP request your client is generating. Both the headers and the body are important.
Modify your Android request to generate the exact same request as the WCF client.

I was also facing same problem with WCF service. 400 Bad request means request parameter value which you are passing to method doesn't match with method's parameter. I have used Base64 string encoding to pass file as method parameter. May it'll help you.

How to use HttpClient (or other HTTP class) to retrieve JSON asynchronously

I've got the content from a HttpClient, but I'm not sure where to go next, in order to parse my JSON result. Also, how do I do this asynchronously so that I can display a wait dialog to the user with the option of cancelling the current request (not bothered about the UI example, how do I setup the HTTP class to be cancellable)?
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet("http://mysite/test.json");
try
{
HttpResponse response = client.execute(request);
// What if I want to cancel now??
HttpEntity entity = response.getEntity();
InputStream inputStream = entity.getContent();
}

Android has a class specifically for this sort of thing: AsyncTask.
See the answer to this question: How to create Http Connection using AsyncTask class?

I'm not a Android programmer but I imagine you need to start a thread.
http://download.oracle.com/javase/tutorial/essential/concurrency/

how to upload the datas to webserver from android mobile

how to upload the datas to webserver from android mobile.Please provide coding

I think this compiles:
HttpPut request = new HttpPut(<uri>);
request.setEntity(new ByteArrayEntity(<your data>));
HttpResponse response = HttpClient.execute(httpPut);
You might want to use the HttpPost instead of HttpPut and also specify the content type on the request.