I have searched everywhere but I couldn't find my answer, is there a way to make a simple HTTP request? I want to request a PHP page / script on one of my websites but I don't want to show the webpage.
If possible I even want to do it in the background (in a BroadcastReceiver)
UPDATE
This is a very old answer. I definitely won't recommend Apache's client anymore. Instead use either:
Retrofit
OkHttp
Volley
HttpUrlConnection
Original Answer
First of all, request a permission to access network, add following to your manifest:
<uses-permission android:name="android.permission.INTERNET" />
Then the easiest way is to use Apache http client bundled with Android:
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = httpclient.execute(new HttpGet(URL));
StatusLine statusLine = response.getStatusLine();
if(statusLine.getStatusCode() == HttpStatus.SC_OK){
ByteArrayOutputStream out = new ByteArrayOutputStream();
response.getEntity().writeTo(out);
String responseString = out.toString();
out.close();
//..more logic
} else{
//Closes the connection.
response.getEntity().getContent().close();
throw new IOException(statusLine.getReasonPhrase());
}
If you want it to run on separate thread I'd recommend extending AsyncTask:
class RequestTask extends AsyncTask<String, String, String>{
#Override
protected String doInBackground(String... uri) {
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response;
String responseString = null;
try {
response = httpclient.execute(new HttpGet(uri[0]));
StatusLine statusLine = response.getStatusLine();
if(statusLine.getStatusCode() == HttpStatus.SC_OK){
ByteArrayOutputStream out = new ByteArrayOutputStream();
response.getEntity().writeTo(out);
responseString = out.toString();
out.close();
} else{
//Closes the connection.
response.getEntity().getContent().close();
throw new IOException(statusLine.getReasonPhrase());
}
} catch (ClientProtocolException e) {
//TODO Handle problems..
} catch (IOException e) {
//TODO Handle problems..
}
return responseString;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
//Do anything with response..
}
}
You then can make a request by:
new RequestTask().execute("http://stackoverflow.com");
unless you have an explicit reason to choose the Apache HttpClient, you should prefer java.net.URLConnection. you can find plenty of examples of how to use it on the web.
we've also improved the Android documentation since your original post: http://developer.android.com/reference/java/net/HttpURLConnection.html
and we've talked about the trade-offs on the official blog: http://android-developers.blogspot.com/2011/09/androids-http-clients.html
Note: The Apache HTTP Client bundled with Android is now deprecated in favor of HttpURLConnection. Please see the Android Developers Blog for more details.
Add <uses-permission android:name="android.permission.INTERNET" /> to your manifest.
You would then retrieve a web page like so:
URL url = new URL("http://www.android.com/");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
try {
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
readStream(in);
}
finally {
urlConnection.disconnect();
}
I also suggest running it on a separate thread:
class RequestTask extends AsyncTask<String, String, String>{
#Override
protected String doInBackground(String... uri) {
String responseString = null;
try {
URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
if(conn.getResponseCode() == HttpsURLConnection.HTTP_OK){
// Do normal input or output stream reading
}
else {
response = "FAILED"; // See documentation for more info on response handling
}
} catch (ClientProtocolException e) {
//TODO Handle problems..
} catch (IOException e) {
//TODO Handle problems..
}
return responseString;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
//Do anything with response..
}
}
See the documentation for more information on response handling and POST requests.
The most simple way is using the Android lib called Volley
Volley offers the following benefits:
Automatic scheduling of network requests. Multiple concurrent network
connections. Transparent disk and memory response caching with
standard HTTP cache coherence. Support for request prioritization.
Cancellation request API. You can cancel a single request, or you can
set blocks or scopes of requests to cancel. Ease of customization, for
example, for retry and backoff. Strong ordering that makes it easy to
correctly populate your UI with data fetched asynchronously from the
network. Debugging and tracing tools.
You can send a http/https request as simple as this:
// Instantiate the RequestQueue.
RequestQueue queue = Volley.newRequestQueue(this);
String url ="http://www.yourapi.com";
JsonObjectRequest request = new JsonObjectRequest(url, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
if (null != response) {
try {
//handle your response
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
queue.add(request);
In this case, you needn't consider "running in the background" or "using cache" yourself as all of these has already been done by Volley.
Use Volley as suggested above. Add following into build.gradle (Module: app)
implementation 'com.android.volley:volley:1.1.1'
Add following into AndroidManifest.xml:
<uses-permission android:name="android.permission.INTERNET" />
And add following to you Activity code:
public void httpCall(String url) {
RequestQueue queue = Volley.newRequestQueue(this);
StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
// enjoy your response
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
// enjoy your error status
}
});
queue.add(stringRequest);
}
It replaces http client and it is very simple.
private String getToServer(String service) throws IOException {
HttpGet httpget = new HttpGet(service);
ResponseHandler<String> responseHandler = new BasicResponseHandler();
return new DefaultHttpClient().execute(httpget, responseHandler);
}
Regards
With a thread:
private class LoadingThread extends Thread {
Handler handler;
LoadingThread(Handler h) {
handler = h;
}
#Override
public void run() {
Message m = handler.obtainMessage();
try {
BufferedReader in =
new BufferedReader(new InputStreamReader(url.openStream()));
String page = "";
String inLine;
while ((inLine = in.readLine()) != null) {
page += inLine;
}
in.close();
Bundle b = new Bundle();
b.putString("result", page);
m.setData(b);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
handler.sendMessage(m);
}
}
As none of the answers described a way to perform requests with OkHttp, which is very popular http client nowadays for Android and Java in general, I am going to provide a simple example:
//get an instance of the client
OkHttpClient client = new OkHttpClient();
//add parameters
HttpUrl.Builder urlBuilder = HttpUrl.parse("https://www.example.com").newBuilder();
urlBuilder.addQueryParameter("query", "stack-overflow");
String url = urlBuilder.build().toString();
//build the request
Request request = new Request.Builder().url(url).build();
//execute
Response response = client.newCall(request).execute();
The clear advantage of this library is that it abstracts us from some low level details, providing more friendly and secure ways to interact with them. The syntax is also simplified and permits to write nice code.
I made this for a webservice to requerst on URL, using a Gson lib:
Client:
public EstabelecimentoList getListaEstabelecimentoPorPromocao(){
EstabelecimentoList estabelecimentoList = new EstabelecimentoList();
try{
URL url = new URL("http://" + Conexao.getSERVIDOR()+ "/cardapio.online/rest/recursos/busca_estabelecimento_promocao_android");
HttpURLConnection con = (HttpURLConnection) url.openConnection();
if (con.getResponseCode() != 200) {
throw new RuntimeException("HTTP error code : "+ con.getResponseCode());
}
BufferedReader br = new BufferedReader(new InputStreamReader((con.getInputStream())));
estabelecimentoList = new Gson().fromJson(br, EstabelecimentoList.class);
con.disconnect();
} catch (IOException e) {
e.printStackTrace();
}
return estabelecimentoList;
}
Look at this awesome new library which is available via gradle :)
build.gradle: compile 'com.apptakk.http_request:http-request:0.1.2'
Usage:
new HttpRequestTask(
new HttpRequest("http://httpbin.org/post", HttpRequest.POST, "{ \"some\": \"data\" }"),
new HttpRequest.Handler() {
#Override
public void response(HttpResponse response) {
if (response.code == 200) {
Log.d(this.getClass().toString(), "Request successful!");
} else {
Log.e(this.getClass().toString(), "Request unsuccessful: " + response);
}
}
}).execute();
https://github.com/erf/http-request
This is the new code for HTTP Get/POST request in android. HTTPClient is depricated and may not be available as it was in my case.
Firstly add the two dependencies in build.gradle:
compile 'org.apache.httpcomponents:httpcore:4.4.1'
compile 'org.apache.httpcomponents:httpclient:4.5'
Then write this code in ASyncTask in doBackground method.
URL url = new URL("http://localhost:8080/web/get?key=value");
HttpURLConnection urlConnection = (HttpURLConnection)url.openConnection();
urlConnection.setRequestMethod("GET");
int statusCode = urlConnection.getResponseCode();
if (statusCode == 200) {
InputStream it = new BufferedInputStream(urlConnection.getInputStream());
InputStreamReader read = new InputStreamReader(it);
BufferedReader buff = new BufferedReader(read);
StringBuilder dta = new StringBuilder();
String chunks ;
while((chunks = buff.readLine()) != null)
{
dta.append(chunks);
}
}
else
{
//Handle else
}
For me, the easiest way is using library called Retrofit2
We just need to create an Interface that contain our request method, parameters, and also we can make custom header for each request :
public interface MyService {
#GET("users/{user}/repos")
Call<List<Repo>> listRepos(#Path("user") String user);
#GET("user")
Call<UserDetails> getUserDetails(#Header("Authorization") String credentials);
#POST("users/new")
Call<User> createUser(#Body User user);
#FormUrlEncoded
#POST("user/edit")
Call<User> updateUser(#Field("first_name") String first,
#Field("last_name") String last);
#Multipart
#PUT("user/photo")
Call<User> updateUser(#Part("photo") RequestBody photo,
#Part("description") RequestBody description);
#Headers({
"Accept: application/vnd.github.v3.full+json",
"User-Agent: Retrofit-Sample-App"
})
#GET("users/{username}")
Call<User> getUser(#Path("username") String username);
}
And the best is, we can do it asynchronously easily using enqueue method
In my app, I need to send all sorts of POST requests to a server. some of those requests have responses and others don't.
this is the code I'm using to send the requests:
private static final String TAG = "Server";
private static final String PATH = "http://10.0.0.2:8001/data_connection";
private static HttpResponse response = null;
private static StringEntity se = null;
private static HttpClient client;
private static HttpPost post = null;
public static String actionKey = null;
public static JSONObject sendRequest(JSONObject req) {
try {
client = new DefaultHttpClient();
actionKey = req.getString("actionKey");
se = new StringEntity(req.toString());
se.setContentEncoding(new BasicHeader(HTTP.CONTENT_ENCODING, "application/json"));
se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
post = new HttpPost(PATH);
post.setEntity(se);
Log.d(TAG, "http request is being sent");
response = client.execute(post);
Log.d(TAG, "http request was sent");
if (response != null) {
InputStream in = response.getEntity().getContent();
String a = convertFromInputStream(in);
in.close();
return new JSONObject(a);
}
} catch (UnsupportedEncodingException e) {
Log.d(TAG, "encoding request to String entity faild!");
e.printStackTrace();
} catch (ClientProtocolException e) {
Log.d(TAG, "executing the http POST didn't work");
e.printStackTrace();
} catch (IOException e) {
Log.d(TAG, "executing the http POST didn't work");
e.printStackTrace();
} catch (JSONException e) {
Log.d(TAG, "no ActionKey");
e.printStackTrace();
}
return null;
}
private static String convertFromInputStream(InputStream in)
throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(in));
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line);
}
return (sb.toString());
}
This is the code for the AsyncTask class that sends the request:
class ServerRequest extends AsyncTask<JSONObject, Void, JSONObject> {
#Override
protected JSONObject doInBackground(JSONObject... params) {
JSONObject req = params[0];
JSONObject response = Server.sendRequest(req);
return response;
}
#Override
protected void onPostExecute(JSONObject result) {
// HANDLE RESULT
super.onPostExecute(result);
}
}
my problem starts when the server doesn't return a response. the AsyncTask thread stays open even after the work is done because the HTTPClient never closes the connection.
Is there a way to not wait for a response? this is something that will definitely add a lot of overhead to the server since all the Android apps trying to connect to it will keep the connection alive, and will probably cause many problems on the app itself.
Basically, what I'm looking for is a method that will allow me to send to POST message and kill the connection right after the sending of the request since there is no response coming my way.
Just, Set ConnectionTimeOut with HttpClient Object, (Code is for your understanding in your case it may be different)
int TIMEOUT_MILLISEC = 30000;
HttpParams httpParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC);
HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC);
HttpClient httpclient = new DefaultHttpClient(httpParams);
HttpPost httppost = new HttpPost(url);
httppost.addHeader("Content-Type", "application/json");
Now, It will terminate the Connection after TimeoOut you defined. But be sure this will throw TimeOutException so You have to handle this exception in your HttpRequest.. (Use Try -catch)
EDIT: Or you can use HttpRequestExecutor class.
From class HttpRequestExecutor of package org.apache.http.protocol
protected boolean canResponseHaveBody (HttpRequest request, HttpResponse response)
Decide whether a response comes with an entity. The implementation in this class is based on RFC 2616. Unknown methods and response codes are supposed to indicate responses with an entity.
Derived executors can override this method to handle methods and response codes not specified in RFC 2616.
I need to make about 15 calls to diferent web services (php) at the application startup.
I'm using the following code for the post
public static String post(String url, List<BasicNameValuePair>
postvalues, HttpClient httpclient) {
try {
if (httpclient == null) {
httpclient = new DefaultHttpClient();
}
HttpPost httppost = new HttpPost(url);
if ((postvalues == null)) {
postvalues = new ArrayList<BasicNameValuePair>();
}
httppost.setEntity(new UrlEncodedFormEntity(postvalues, "UTF-8"));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
return requestToString(response);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
private static String requestToString(HttpResponse response) {
String result = "";
try {
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 + "\n");
}
in.close();
result = str.toString();
} catch (Exception ex) {
result = "Error";
}
return result;
}
The problem is that some of the petitions must be requested in a given order and each request takes about 1-2 second so the "Loading splash" takes about 10 seconds.
So my question is:Since all the connections are to the same server, how can I improve this delay? Is there some way of open a connection and send all the petitions through that "tunnel" reducing the delay?
NOTE: I tested the code and the requests take the same time reusing the httpclient using a new one in each connection
Thanks
What you have in mind is a HTTP persistent connection which reuses the TCP connection.
About this topic there is already a good question & answer here on Stackoverflow:
Persistent HttpURLConnections on Android
I want my android app to get data from an online database. Here are the two scenarios:
When I create my db with xampp and I am using the httpost function with my local machines' ip as argument I see as output what I expect to see (the database at logcat).
My question is: if I run the application from my phone, will it connect to my local machine server or not?
I also have a site (lets say mysite.com) and in order not to buy another server I am placing the php file and the database on that server. But then my android app connects (or so I think) to the server, but it prints out at logcat the whole html site. I am thinking that this is because the server requires a username and a password and I do not know if I provided them or not?
So, what do you suggest to do? I want my database being sent to my app (so as to use it later).
My code is shown below (I have in comments the only that changes between 2 scenarios)
public class MainActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setImageClickListener();
}
private void setImageClickListener() {
ImageView map_image=(ImageView)findViewById(R.id.map_icon);
map_image.setOnTouchListener(new ImageView.OnTouchListener() {
//OnTouchListener listener = new OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
if(!(event.getAction() == MotionEvent.ACTION_DOWN))
return false; //If the touch event was not putting the finger down on the screen, return false(Actions may be move, up, and so on)
final float x = event.getX();
final float y = event.getY();
//System.out.println("Coordinates of button pressed are: X is %d"+x+" and Y is %d"+ y);
if(x>335 && x<395 && y>225 && y< 235)
DoFirst();
return true;
}
});
}
#SuppressWarnings("null")
private void DoFirst() {
Log.d("SnowReportApp","Do first thing");
setContentView(R.layout.layout_1);
String result = "";
InputStream is = null;
StringBuilder sb=null;
//the year data to send
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();//() before
nameValuePairs.add(new BasicNameValuePair("year","1980"));
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("192.168.1.67/test.php"); // only this changes to my server url : mysite.com/httpdocs/test.php
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
//parse JSON data
try{
//JSONObject json_data_1 = new JSONObject(result);
JSONArray jArray = new JSONArray(result);
for(int i=0;i<jArray.length();i++){
JSONObject json_data = jArray.getJSONObject(i);
Log.i("log_tag","id: "+json_data.getInt("id")+
", name: "+json_data.getString("name")+
", sex: "+json_data.getInt("sex")+
", birthyear: "+json_data.getInt("birthyear")
);
}
}catch(JSONException e){
Log.e("log_tag", "Error parsing data "+e.toString());
}
}
My php file located on either c:\xampp\htdocs or on mysite server is this:
<?php
mysql_connect("127.0.0.1","root","");
mysql_select_db("peopledata");
$q=mysql_query("SELECT * FROM people WHERE birthyear>'".$_REQUEST['year']."'");
while($e=mysql_fetch_assoc($q))
$output[]=$e;
print(json_encode($output));
mysql_close();?>
My question is: if I run the application from my phone, will it
connect to my local machine server or not?
The answer is probably not. It really all depends on:
Whether you're using Wifi or Carrier data (3G, etc)
Whether your DB ports are open (PC firewall)
If Carrier data, is your PC reachable from the Internet (static IP)
You're better off using mysite.com for your DB and whatever backend you need.
As for your other questions, I cannot answer them as they're quite vague. Consider researching your problem some more and perhaps come back with a targeted set of questions.
I have get a correct login using HttpRequest to work. It prints the correct html form of the logn page in my toast (just for testing). Now I want to set a cookie from that request. How is this possible?
If it necessary I can provide some code.
I already know about the CookieManager class, but how can I successfully do it?
Thanks in advance!
My code:
public String getPostRequest(String url, String user, String pass) {
HttpClient postClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse response;
try {
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("login", user));
nameValuePairs.add(new BasicNameValuePair("pass", pass));
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs, HTTP.UTF_8));
response = postClient.execute(httpPost);
if(response.getStatusLine().getStatusCode() == 200) {
HttpEntity entity = response.getEntity();
if (entity != null) {
InputStream instream = entity.getContent();
String result = convertStreamToString(instream);
instream.close();
return result;
}
}
} catch (Exception e) {}
Toast.makeText(getApplicationContext(),
"Connection failed",
Toast.LENGTH_SHORT).show();
return null;
}
private String convertStreamToString(InputStream is) {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
Well, this is pretty much it. convertStreamToString() function converts the InputStream into a String (plain HTML code), which I "toast" out to just test it (so it work), so the code is working though. Now to set the cookie. :-)
This is what I've reached for now:
// inside my if (entity != null) statement
List<Cookie> cookies = postClient.getCookieStore().getCookies();
String result = cookies.get(1).toString();
return result;
When I have logged in, the CookieList id 1 contains a value, otherwise the value is standard. So for now I know the difference in value, but how can I continue?
I think Android ships with Apache HttpClient 4.0.
You can check Chapter 3. HTTP state management topic from HttpClient Tutorial.
You can also refer similar questions on SO:
Android project using httpclient --> http.client (apache), post/get method
How do I manage cookies with HttpClient in Android and/or Java?
Also Check this example for usage: http://svn.apache.org/repos/asf/httpcomponents/httpclient/branches/4.0.x/httpclient/src/examples/org/apache/http/examples/client/ClientFormLogin.java