Develop Reference

how to use URL to post data with HttpClient in android

I have to send/post some data to .svc Web Service that basically connect to remote database. I'm using JSONStringer to send the data but every time response status is false. My data is not sent. How to use HttpPost in Android . Can someone help me how to solve this .
Here is my webservice code
String namespace = "http://103.24.4.60/xxxxx/MobileService.svc";
public void ActivityUpload( final String strCurrentDateTime, final String strTitle, final String replaceDescChar, final String editedHashTag)
{
new AsyncTask<String, Void, String>()
{
#Override
protected String doInBackground(String... arg0)
{
String line = "";
try
{
Log.e("ActionDate "," = "+ strCurrentDateTime);
Log.e("ActivityId"," = "+strActivityId);
Log.e("UserId"," = "+str_UserId);
Log.e("ObjectId"," = "+strVessId);
Log.e("Name"," = "+strTitle);
Log.e("Remark"," = "+replaceDescChar);
Log.e("Status"," = "+"PENDING");
Log.e("Type"," = "+strType);
Log.e("starflag"," = "+0);
Log.e("HashTag"," = "+editedHashTag);
Log.e("Authentication_Token"," = "+str_Authentication_Token);
// make web service connection
HttpPost request = new HttpPost(namespace + "/Upd_Post_Activity");
request.setHeader("Accept", "application/json");
request.setHeader("Content-type", "application/json");
// Build JSON string
JSONStringer TestApp = new JSONStringer().object()
.key("ActionDate").value(strCurrentDateTime)
.key("ActivityId").value(strActivityId)
.key("UserId").value(str_UserId)
.key("ObjectId").value(strVessId)
.key("Name").value(strTitle)
.key("Remark").value(replaceDescChar)
.key("Status").value("PENDING")
.key("Type").value(strType)
.key("starflag").value("0")
.key("HashTag").value(editedHashTag)
.key("Authentication_Token").value(str_Authentication_Token).endObject();
StringEntity entity = new StringEntity(TestApp.toString());
Log.d("****Parameter Input****", "Testing:" + TestApp);
request.setEntity(entity);
// Send request to WCF service
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(request);
Log.d("WebInvoke", "Saving: " + response.getStatusLine().toString());
// Get the status of web service
BufferedReader rd = new BufferedReader(new InputStreamReader(
response.getEntity().getContent()));
// print status in log
while ((line = rd.readLine()) != null) {
Log.d("****Status Line***", "Webservice: " + line);
}
} catch (Exception e) {
e.printStackTrace();
}
return line;
}
}.execute();
}
Here is input Parameter.
****Parameter Input****﹕ Testing:{"ActionDate":"2016-01-21%2014:20:43%20PM","ActivityId":"120160119180421058","UserId":"125","ObjectId":"1","Name":"Title2","Remark":"Test%20two","Status":"PENDING","Type":"3","starflag":"0","HashTag":"990075","Authentication_Token":"6321D079-5B28-4F3F-AEE7-D59A1B9EFA59"}
Thanks in advanced.

realize android httpclients are in process of deprecation ( in favor of httpsurlconnection ) but, these httpclients are still used pretty widely. On gradle builds, regard the deprication, and with small dependency lib tweeks , httpclient may be used for some time still.
( still gonna use httpclient ? )
Put android aside for a min.
learn how to CURL with JSON body for tests that show you what you EXACT JSON in body and exact HEADERS you will need to get success http result to a post ... ref here
Once you have that you can then go about transferring your curl test's components over to android.httpclient.exec.POST using httpclient of your choice.
Set the same group of Headers you had over in curl tests in your android post. apache.httpclient sample
2.a. make sure that default list of headers from the clients 'request' constructor does NOT include by default some headers you DO NOT want... In order to assure of this ,you probably will need to turn on HEADER logging for your client.... java example logger . remove unnecessary headers included by the framework constructor of POST.
2.b android logger (WIRE, HEADERS) is diff from and may take some digging , depend on what client is in use.
with the same headers as curl tests, set the http.posts request.entity to either a string or a properly encoded array of bytes containing the same JSON body used in the curl tests.
3.A. depending on the JSON lib, create your message objects and then convert the objects to some friendly type for enclosure in an entity for the post ie use a 'writer' to convert objects to a serialized string with the JSON.
reqRole = new ObjectMapper().createObjectNode();
reqRole.put("__type", "Pointer");
reqRole.put("className", "_Role");
reqRole.put("objectId", roleId);
rootOb.put("requestedRole", reqRole);
rootOb.put("requestedBy",usersArr);
StringWriter writer = new StringWriter();
try {
new ObjectMapper().writeValue(writer, rootOb)
..
String http-post-str=writer.toString();
3.B. wrap the string with json in the POST request...
httpPost.setEntity(new StringEntityHC4(http-post-str));
exec the request and youll get the same results you got in curl because the headers are same or nearly same and the body is the same , encoded string of json. same input = same result

Getting json response from servlet to Android

I have a servlet that has the following purpose:
Receive data via the URL (that is, using get). Then returns a message, based on this input, back to the caller. I am new to this stuff, but have come to learn that using json (actually, Gson) is suitable for this.
My question now is, how do I retrieve this json message? What URL do I target? The relevant lines in the servlet are:
String json = new Gson().toJson(thelist);
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");
response.getWriter().println(json);
This is how I try to retrieve the json:
try{
DefaultHttpClient defaultClient = new DefaultHttpClient();
HttpGet httpGetRequest = new HttpGet("http://AnIPno:8181/sample/response?first=5&second=92866");
HttpResponse httpResponse = defaultClient.execute(httpGetRequest);
BufferedReader reader = new BufferedReader(new InputStreamReader(httpResponse.getEntity().getContent(), "UTF-8"));
String json = reader.readLine();
JSONObject jsonObject = new JSONObject(json);
} catch(Exception e){
e.printStackTrace();
}
But apparently this does not work, as I have found jsonObject has a size of 0 (it should be an array with three elements).
Previously, I had a write() instead of println() in the servlet. I'm not sure if that matters in this case. But I'm assuming I've misunderstood something about how the json object is retrieved. Is it not enough to point it towards the URL of the servlet?

Reading an InputStream whether from a File on the file system or from an HTTP request is, in most cases, the same.
What you have is correct only if your servlet wrote a single line. If the Gson object toString() method returns multiple lines, you're going to have to read multiple lines from the InputStream. I like to use the Scanner class for reading from an InputStream.
try {
DefaultHttpClient defaultClient = new DefaultHttpClient();
HttpGet httpGetRequest = new HttpGet("http://localhost:8080/cc/jsonyeah");
HttpResponse httpResponse = defaultClient.execute(httpGetRequest);
Scanner scanner = new Scanner(httpResponse.getEntity().getContent(), "UTF-8");
while(scanner.hasNextLine()) { // scanner looks ahead for an end-of-line
json += scanner.nextLine() + "\n"; // read the full line, you can append a \n
}
// do your serialization
} catch(Exception e) {
e.printStackTrace();
}
So we've done the same thing we would've done if we were reading from a file. Now the json object contains the json you received from the servlet, as a String.
For the serialization, you have a few options.
A Gson object has an overloaded method fromJson() that can take a String or a Reader, among other things.
From where we are with the code above, you can do
MyClass instance = new Gson().fromJson(json, MyClass.class);
where MyClass is the type you are trying to create. You will have to use a TypeToken for generic classes (such as a list). TypeToken is an abstract class, so generate an anonymous class and call getType()
Type type = new com.google.gson.reflect.TypeToken<List<String>>(){}.getType();
List<MyClass> list = new Gson().fromJson(json, type);
Another option is to use the overloaded method that takes a Reader directly instead of reading line by line from the InputStream:
BufferedReader reader = new BufferedReader(new InputStreamReader(httpResponse.getEntity().getContent(), "UTF-8"));
MyClass instance = new Gson().fromJson(reader , MyClass.class);
You'll get to skip a step.
Don't forget to close your streams.

I have this function to readJsonData from a a request to a JSON String. You can use this function to retrieve the JSON, then use GSON to parse it to the object that you like. It works for my application. Hope it works for you too.
protected String readJson(HttpResponse resp)
throws IOException {
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(
resp.getEntity().getContent()));
StringBuffer buffer = new StringBuffer();
int read;
char[] chars = new char[1024];
while ((read = reader.read(chars)) != -1)
buffer.append(chars, 0, read);
} finally {
if (reader != null)
reader.close();
}
return buffer.toString();
}
So based on your code. I guess this should work:
String jsonData = readJson(httpResponse);
YourObject obj = new Gson().fromJson(jsonData, YourObject.class);
Before trying this, make sure your servlet prints out the JSON data that you want. I suggest using these Chrome Extensions: Postman - REST Client and JSON Formatter, to test your data from servlet. It's pretty helpful.

Android - How to realize REST GET function for REST API in skydrive

Does anyone know how to use Skydrive REST API in Android?
(documented here http://msdn.microsoft.com/de-de/library/live/hh243648.aspx)
All Data that are needed for access are already stored!
private String AccessToken;
private String AuthenticationToken;
private String RefreshToken;
private String ExpiresIn;
private String Scope;
Is it right to use
HttpClient client = new DefaultHttpClient();
Does anyone have a full example?
Any ideas or suggestion would be helpful. Thank you.

You can do something like this.
InputStream result = null;
HttpClient httpClient = new DefaultHttpClient();
HttpGet get = new HttpGet("https://apis.live.net/v5.0/me/albums?access_token=" + AccessToken); // For example
HttpResponse response = httpClient.execute(get);
if (response != null && response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
BufferedHttpEntity bufferedHttpEntity = new BufferedHttpEntity(response.getEntity());
result = bufferedHttpEntity.getContent();
} else {
// insert error handling
}
Depending on what request you are making you may need to use HttpPut, HttpPost, HttpDelete, etc. instead of HttpGet.
GET - Returns the representation of a resource.
POST - Adds a new resource to a collection.
PUT - Updated to the location that was specified as the target URL, or add a resource there, add a resource if one does not exist.
DELETE - Deletes a resource.
If the request requires a body, you can add it with setEntity() which takes an HttpEntity object.

Http Post Request in Android won't return appropriate data?

Okay, so I was trying to send Http Post Requests to this one site, and I sniffed the sent request with wireshark thus getting the text data from the post request of this site. I used this in a stock Java application, and it worked perfectly fine. I could use the post method regularly with no problem whatsoever, and it would return the appropriate website. Then I tried doing this with Android. Instead of returning the actual html data after executing the post request, it returns the regular page html data untouched. It DOES send a post request (sniff with wireshark again), it just doesn't seem to get the appropriate response. I took the exact same method used from another one of my projects, which worked perfectly fine in that project, and pasted it into my new project. I added the INTERNET user permission in Android, so there's nothing wrong with that. The only visible difference is that I used NameValuePairs in the other one (the one that worked) and in this one I'm directly putting the string into a StringEntity without encoding (using UTF-8 encoding screws up the String though). I used this exact same line of text in regular Java like I said, and it worked fine with no encoding. So what could be the problem? This is the code:
public static String sendNamePostRequest(String urlString) {
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(urlString);
StringBuffer sb = new StringBuffer();
try {
post.setEntity(new StringEntity(
"__EVENTTARGET=&__EVENTARGUMENT=&__VIEWSTATE=%2FwEPDwULLTE3NDM5MzMwMzRkZA%3D%3D&__EVENTVALIDATION=%2FwEWBAL%2B%2B4CfBgK52%2BLYCQK1gpH7BAL0w%2FPHAQ%3D%3D&_nameTextBox=John&_zoekButton=Zoek&numberOfLettersField=3"));
HttpResponse response = client.execute(post);
HttpEntity entity = response.getEntity();
BufferedReader br = new BufferedReader(new InputStreamReader(
entity.getContent()));
String in = "";
while ((in = br.readLine()) != null) {
sb.append(in + "\n");
}
br.close();
} catch (Exception e) {
e.printStackTrace();
}
return sb.toString();
}
Can you see what's wrong here?

Gain URL from google image search in android

I am trying to be able to view the source code of a webpage after being given a URL in order to parse the text for a certain string which represents and image url.
I found this post which is pretty much what I am after trying to do but can't get it working:
Post
This is my code below.
public String fetchImage() throws ClientProtocolException, IOException {
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet("www.google.co.uk/images?q=songbird+oasis");
HttpResponse response = client.execute(request);
String html = "";
InputStream in = response.getEntity().getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
StringBuilder str = new StringBuilder();
String line = null;
while((line = reader.readLine()) != null)
{
str.append(line);
}
in.close();
html = str.toString();
return html;
}
but for some reason it just does not work. It forces me to use a try catch statement in calling the method. Once this works I think it will simple from here using regex to find the string "href="/imgres?imgurl=........jpg" to find the url of a jpg image to then be shown in an image view.
Please tell me if i'm going at this all wrong.

First, Google has a search API, which will be a better solution than the scraping you are going through, since the API will be reliable, and your solution will not be.
Second, use the BasicResponseHandler pattern for string responses, as it is much simpler.
Third, saying something "just does not work" is a pretty useless description for a support site like this one. If it crashes, as kgiannakakis pointed out, you will have an exception. Use adb logcat, DDMS, or the DDMS perspective in Eclipse to examine the stack trace and find out what the exception is. That will give you some clues for how to solve whatever problem you have.