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 wrote a little programm, that reads an XML-File via http-get.
Loacally it's running fine.
But on the server it keeps breaking without any exception, except a nullpointer because of the empty result
I'm using the apache http lib.
Here is the class, i added the numbers, to track the exact point, where it stops working.
public void get(String url, String user, String pass, File outfile) throws IOException
{
log.info("1");
CredentialsProvider credsProvider = new BasicCredentialsProvider();
credsProvider.setCredentials(new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT, AuthScope.ANY_REALM, "basic"),
new UsernamePasswordCredentials(user, pass));
log.info("2");
CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(credsProvider).build();
HttpResponse response = null;
log.info("6");
InputStream content = null;
FileOutputStream outputStream = null;
try
{
HttpGet httpGet = new HttpGet(url);
log.info("3");
httpGet.addHeader("Content-Type", "text/xml");
log.info("4");
httpGet.addHeader("Accept", "text/xml");
log.info("5");
log.info("6");
log.info("7");
outputStream = new FileOutputStream(outfile);
log.info("8");
response = httpClient.execute(httpGet);
log.info("9");
log.info("response: {}", response);
log.info("10");
content = response.getEntity().getContent();
log.info("11");
log.info("content: {}", content);
log.info("12");
IOUtils.copy(content, outputStream);
log.info("13");
}
catch (Exception e)
{
log.error("", e);
}
finally
{
try
{
log.info("14");
log.info(String.valueOf(content));
content.close();
outputStream.close();
}
catch (IOException e)
{
log.error("Error while closing Streams", e);
}
}
}
Here are the log snipets; I tried to mask every sensible data and i hope i didn't miss anything
Local log snipet
Remote log snipet
As you can see, the numbers stop after 8 and start in the finally block again with 14. the rest is missing and I have no idea, why.
The used URL is reachable via browser or comandline.
The problem is a bit tricky: you are running into some sort of Error here. Probably NoClassDefFoundError or something alike.
But as you are catching for Exception this piece of code simply doesn't "see" the real problem.
So to debug the problem: either check the server log files or change your code to catch Throwable instead of Exception.
My biggest issue is that I do not have the certificate (public and private key pair). The certificate is installed in the weblogic trust store and is the default certificate presented when making a request to the web application I am just not sure how I can make the call without the certificate loaded on the file system.
I tried using Apache HTTP client and Javax Http Client hoping that when I would make the call it would also send the certificate.
private void testCall(String path) {
URI uri = null;
try {
uri = new URIBuilder().setScheme("https").setHost("secure.url.com")
.setPath("/"+path)
.build();
} catch (URISyntaxException e) {
status = "Error Occured Building URL";
}
HttpGet httpget = new HttpGet(uri);
builtUrl = httpget.getURI().toString();
printContent(httpget);
}
private void printContent(HttpGet getRequest){
try {
CloseableHttpClient httpClient = HttpClients.createDefault();
HttpResponse response = httpClient.execute(getRequest);
status = response.getStatusLine().toString();
HttpEntity entity = response.getEntity();
contentRes = EntityUtils.toString(entity );
} catch (ClientProtocolException e) {
status = "Error Occured during Client Protocol" + e.toString();
} catch (ParseException e) {
status = "Error Occured during Parse Protocol" + e.toString();
} catch (IOException e) {
status = "Error Occured during Client Protocol" + e.toString();
}
}
I'm using HttpClient 4.3 with a PoolingHttpClientConnectionManager and two threads which each connect to a REST API. Both are permanently sending requests. It works well for some minutes, but then, the requests begin to timeout. While browsing, even Chrome cannot establish connections to websites. This is my code for sending a request:
String sendGETApache(HttpGet httpGet) {
try {
CloseableHttpResponse response = httpClient.execute(httpGet); //, httpContext);
HttpEntity entity = null;
try {
entity = response.getEntity();
if(entity != null) {
String s = EntityUtils.toString(entity);
return s;
}
} catch (Exception e) {
e.printStackTrace();
httpGet.abort();
} finally {
EntityUtils.consume(entity);
response.close();
}
} catch (Exception e) {
httpGet.abort();
e.printStackTrace();
} finally {
httpGet.releaseConnection();
}
return "";
}
The HttpClient is an unique object, shared between both threads.
I tried already limiting DefaultMaxPerRoute and MaxTotal to 1 and 2, I even used really big values, no result.
I even implemented an extra thread which calls closeExpiredConnections() and closeIdleConnections() repeatedly, also no improvement.
Do you have any idea what I could do? I think somewhere resources are leaking, but I don't knwo where...
Thank you
I need a simple code example of sending http post request with post parameters that I get from form inputs.
I have found Apache HTTPClient, it has very reach API and lots of sophisticated examples, but I couldn't find a simple example of sending http post request with input parameters and getting text response.
Update: I'm interested in Apache HTTPClient v.4.x, as 3.x is deprecated.
Here's the sample code for Http POST, using Apache HTTPClient API.
import java.io.InputStream;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.PostMethod;
public class PostExample {
public static void main(String[] args){
String url = "http://www.google.com";
InputStream in = null;
try {
HttpClient client = new HttpClient();
PostMethod method = new PostMethod(url);
//Add any parameter if u want to send it with Post req.
method.addParameter("p", "apple");
int statusCode = client.executeMethod(method);
if (statusCode != -1) {
in = method.getResponseBodyAsStream();
}
System.out.println(in);
} catch (Exception e) {
e.printStackTrace();
}
}
}
I pulled this code from an Android project by Andrew Gertig that I have used in my application. It allows you to do an HTTPost. If I had time, I would create an POJO example, but hopefully, you can dissect the code and find what you need.
Arshak
https://github.com/AndrewGertig/RubyDroid/blob/master/src/com/gertig/rubydroid/AddEventView.java
private void postEvents()
{
DefaultHttpClient client = new DefaultHttpClient();
/** FOR LOCAL DEV HttpPost post = new HttpPost("http://192.168.0.186:3000/events"); //works with and without "/create" on the end */
HttpPost post = new HttpPost("http://cold-leaf-59.heroku.com/myevents");
JSONObject holder = new JSONObject();
JSONObject eventObj = new JSONObject();
Double budgetVal = 99.9;
budgetVal = Double.parseDouble(eventBudgetView.getText().toString());
try {
eventObj.put("budget", budgetVal);
eventObj.put("name", eventNameView.getText().toString());
holder.put("myevent", eventObj);
Log.e("Event JSON", "Event JSON = "+ holder.toString());
StringEntity se = new StringEntity(holder.toString());
post.setEntity(se);
post.setHeader("Content-Type","application/json");
} catch (UnsupportedEncodingException e) {
Log.e("Error",""+e);
e.printStackTrace();
} catch (JSONException js) {
js.printStackTrace();
}
HttpResponse response = null;
try {
response = client.execute(post);
} catch (ClientProtocolException e) {
e.printStackTrace();
Log.e("ClientProtocol",""+e);
} catch (IOException e) {
e.printStackTrace();
Log.e("IO",""+e);
}
HttpEntity entity = response.getEntity();
if (entity != null) {
try {
entity.consumeContent();
} catch (IOException e) {
Log.e("IO E",""+e);
e.printStackTrace();
}
}
Toast.makeText(this, "Your post was successfully uploaded", Toast.LENGTH_LONG).show();
}
HTTP POST request example using Apache HttpClient v.4.x
HttpClient httpClient = HttpClients.createDefault();
HttpPost httpPost = new HttpPost(url);
MultipartEntityBuilder builder = MultipartEntityBuilder.create();
builder.addTextBody("param1", param1Value, ContentType.TEXT_PLAIN);
builder.addTextBody("param2", param2Value, ContentType.TEXT_PLAIN);
HttpEntity multipart = builder.build();
httpPost.setEntity(multipart);
HttpResponse response = httpClient.execute(httpMethod);
http://httpunit.sourceforge.net/doc/cookbook.html
use PostMethodWebRequest and setParameter method
shows a very simple exapmle where you do post from Html page, servlet processes it and sends a text response..
http://java.sun.com/developer/onlineTraining/Programming/BasicJava1/servlet.html