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
I have got this code on my application, that I copied and pasted from stackoverflow. All it does is do a http request to a website, and return its content (and it works perfect).
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);
ShowMsg(thisone,result);
}
}
When I use it to get the content of a website, like this way:
new RequestTask().execute("http://www.stackoverflow.com");
It was perfectly well. It shows the entire code of the website, and everything nice. But when I try to get the content of a website I have running on my apache server, it shows nothing:
new RequestTask().execute("http://127.0.0.1");
Why is this happening?
Localhost from android is .... the android phone. You need to put in the name or ip of your apache server.
So if you are running a local emulator, you should put in the IP of your machine.
I am using the following guide demonstrated by Konstantin Burov on a Stackoverflow post (Make an HTTP request with android):
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);
out.close();
String responseString = out.toString();
//..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);
out.close();
responseString = out.toString();
} 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");
My question is how do I now post the actual results in a string? All i'm getting is the address when I do new RequestTask().execute(url).toString();
Your response is delivered as an argument to onPostExecute(String).
You're supposed to handle the response in this method. Be aware that onPostExecute(String) is run on the UI thread, so you cannot do lengthy operations as part of this method.
When you call new RequestTask().execute(url).toString(); you're simply invoking the toString() method of your AsyncTask (check the return value of execute(): it simply returns this, i.e. the AsyncTask that you're calling execute() on).
I'm going to write an app that have more than 50 request for every user.should i get the access token for every user that Authenticated?
and how to do it with java?i get the APIs with but how to get the access token?
class GetRequestAsyncTask extends AsyncTask<String, String, String> {
#Override
protected String doInBackground(String... uri) {
DefaultHttpClient http_client = new DefaultHttpClient();
HttpResponse response;
String respondString;
try {
response = http_client.execute(new HttpGet(uri[0]));
StatusLine statusLine = response.getStatusLine();
if (statusLine.getStatusCode() == HttpStatus.SC_OK) {
ByteArrayOutputStream out = new ByteArrayOutputStream();
response.getEntity().writeTo(out);
respondString = out.toString();
out.close();
Log.w("FLAG!", "Data downloaded:"+respondString);
return respondString;
} else {
response.getEntity().getContent().close();
throw new IOException(statusLine.getReasonPhrase());
}
} catch (ClientProtocolException e) {
Log.e("ClientProtocolException GetTask", e.toString());
return "";
} catch (IOException e) {
Log.e("IOException GetTask", e.toString());
return "";
}
}
Who are the users of this?
If you ask your users to log into their Instagram account, and authorize your app, then you can make 5000 requests per hour per user:
http://instagram.com/developer/limits/
If you just use your key, you are limited to 5000 requests per hour, no matter how many users you have.
I am having difficulty trying to get the body of the HTTP response from the string. So according to my code, I should have response from the PHP page in the string called "responseString" however because this is in an ASynchTask, I can not access that string anywhere else, so how can I receive the string?
For example, I would like to shoot this string into a text view for testing purposes, how can I do that? Am I reading the code incorrectly? Is the response I am getting not being put into that string?
Here is my code:
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);
out.close();
responseString = out.toString();
} 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);
}
}
I am using the following to execute:
new RequestTask().execute("http://www.mywebsite.com/android/registercheck.php?first=" + first2 + "&last=" + last2 + "&dispname=" + display2 + "&email=" + email2 + "&password=" + password2 );
after executing the doInBackground the onPostExecute will launch directly, and there you can update the UI so since you are returning responseString, then in onPostExecute put it in a TextView
The return of doInBackgound is the arugment of onPostExecute so the String result is your responseString.
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
tv.setText(result);
}
I think your problem don't solved yet.so,
for Log or Toast use following code:
class RequestTask extends AsyncTask<String, String, String>{
String responseString = "";
#Override
protected String doInBackground(String... uri) {
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response;
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);
out.close();
responseString = out.toString();
} 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);
Log.d("Result is", responseString );
Toast.makeText(YourClass.this , responseString , Toast.LENGTH_SHORT).show();
}
}