Sending POST data in Android

I'm experienced with PHP, JavaScript and a lot of other scripting languages, but I don't have a lot of experience with Java or Android.

I'm looking for a way to send POST data to a PHP script and display the result.

Note (Oct 2020): AsyncTask used in the following answer has been deprecated in Android API level 30. Please refer to Official documentation or this blog post for a more updated example

Updated (June 2017) Answer which works on Android 6.0+. Thanks to @Rohit Suthar, @Tamis Bolvari and @sudhiskr for the comments.

    public class CallAPI extends AsyncTask<String, String, String> {
    
        public CallAPI(){
            //set context variables if required
        }
    
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }
    
         @Override
         protected String doInBackground(String... params) {
            String urlString = params[0]; // URL to call
            String data = params[1]; //data to post
            OutputStream out = null;

            try {
                URL url = new URL(urlString);
                HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
                out = new BufferedOutputStream(urlConnection.getOutputStream());

                BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out, "UTF-8"));
                writer.write(data);
                writer.flush();
                writer.close();
                out.close();

                urlConnection.connect();
            } catch (Exception e) {
                System.out.println(e.getMessage());
            }
        }
    }

References:

• https://developer.android.com/reference/java/net/HttpURLConnection.html
• https://stackoverflow.com/questions/9767952/how-to-add-parameters-to-httpurlconnection-using-post

Original Answer (May 2010)

Note: This solution is outdated. It only works on Android devices up to 5.1. Android 6.0 and above do not include the Apache http client used in this answer.

Http Client from Apache Commons is the way to go. It is already included in android. Here's a simple example of how to do HTTP Post using it.

public void postData() {
    // Create a new HttpClient and Post Header
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost("http://www.yoursite.com/script.php");

    try {
        // Add your data
        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
        nameValuePairs.add(new BasicNameValuePair("id", "12345"));
        nameValuePairs.add(new BasicNameValuePair("stringdata", "Hi"));
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

        // Execute HTTP Post Request
        HttpResponse response = httpclient.execute(httppost);
        
    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
    } catch (IOException e) {
        // TODO Auto-generated catch block
    }
} 

for Android = > 5

The org.apache.http classes and the AndroidHttpClient class have been deprecated in Android 5.1. These classes are no longer being maintained and you should migrate any app code using these APIs to the URLConnection classes as soon as possible.

https://developer.android.com/about/versions/android-5.1.html#http

Thought of sharing my code using HttpUrlConnection

public String  performPostCall(String requestURL,
        HashMap<String, String> postDataParams) {

    URL url;
    String response = "";
    try {
        url = new URL(requestURL);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setReadTimeout(15000);
        conn.setConnectTimeout(15000);
        conn.setRequestMethod("GET");
        conn.setDoInput(true);
        conn.setDoOutput(true);


        OutputStream os = conn.getOutputStream();
        BufferedWriter writer = new BufferedWriter(
                new OutputStreamWriter(os, "UTF-8"));
        writer.write(getPostDataString(postDataParams));

        writer.flush();
        writer.close();
        os.close();
        int responseCode=conn.getResponseCode();

        if (responseCode == HttpsURLConnection.HTTP_OK) {
            String line;
            BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
            while ((line=br.readLine()) != null) {
                response+=line;
            }
        }
        else {
            response="";    

        }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return response;
}

...

private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException{
        StringBuilder result = new StringBuilder();
        boolean first = true;
        for(Map.Entry<String, String> entry : params.entrySet()){
            if (first)
                first = false;
            else
                result.append("&");

            result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
            result.append("=");
            result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
        }

        return result.toString();
    }

---

also you can Post method :

conn.setRequestMethod("POST");

---

Update 21/02/2016

for post request with json , see this example :

public class Empty extends
        AsyncTask<Void, Void, Boolean> {

    String urlString = "http://www.yoursite.com/";

    private final String TAG = "post json example";
    private Context context;

    private int advertisementId;

    public Empty(Context contex, int advertisementId) {

        this.context = contex;
        this.advertisementId = advertisementId;
    }

    @Override
    protected void onPreExecute() {
        Log.e(TAG, "1 - RequestVoteTask is about to start...");

    }

    @Override
    protected Boolean doInBackground(Void... params) {
        boolean status = false;

        String response = "";
        Log.e(TAG, "2 - pre Request to response...");

        try {
            response = performPostCall(urlString, new HashMap<String, String>() {

                        private static final long serialVersionUID = 1L;

                        {
                            put("Accept", "application/json");
                            put("Content-Type", "application/json");
                        }
                    });
            Log.e(TAG, "3 - give Response...");
            Log.e(TAG, "4 " + response.toString());
        } catch (Exception e) {
            // displayLoding(false);

            Log.e(TAG, "Error ...");
        }
        Log.e(TAG, "5 - after Response...");

        if (!response.equalsIgnoreCase("")) {
            try {
                Log.e(TAG, "6 - response !empty...");
                //
                JSONObject jRoot = new JSONObject(response);
                JSONObject d = jRoot.getJSONObject("d");

                int ResultType = d.getInt("ResultType");
                Log.e("ResultType", ResultType + "");

                if (ResultType == 1) {

                    status = true;

                }

            } catch (JSONException e) {
                // displayLoding(false);
                // e.printStackTrace();
                Log.e(TAG, "Error " + e.getMessage());
            } finally {

            }
        } else {
            Log.e(TAG, "6 - response is empty...");

            status = false;
        }

        return status;
    }

    @Override
    protected void onPostExecute(Boolean result) {
        //
        Log.e(TAG, "7 - onPostExecute ...");

        if (result) {
            Log.e(TAG, "8 - Update UI ...");

            // setUpdateUI(adv);
        } else {
            Log.e(TAG, "8 - Finish ...");

            // displayLoding(false);
            // finish();
        }

    }

    public String performPostCall(String requestURL,
                                  HashMap<String, String> postDataParams) {

        URL url;
        String response = "";
        try {
            url = new URL(requestURL);

            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(context.getResources().getInteger(
                    R.integer.maximum_timeout_to_server));
            conn.setConnectTimeout(context.getResources().getInteger(
                    R.integer.maximum_timeout_to_server));
            conn.setRequestMethod("POST");
            conn.setDoInput(true);
            conn.setDoOutput(true);

            conn.setRequestProperty("Content-Type", "application/json");

            Log.e(TAG, "11 - url : " + requestURL);

			/*
             * JSON
			 */

            JSONObject root = new JSONObject();
            //
            String token = Static.getPrefsToken(context);

            root.put("securityInfo", Static.getSecurityInfo(context));
            root.put("advertisementId", advertisementId);

            Log.e(TAG, "12 - root : " + root.toString());

            String str = root.toString();
            byte[] outputBytes = str.getBytes("UTF-8");
            OutputStream os = conn.getOutputStream();
            os.write(outputBytes);

            int responseCode = conn.getResponseCode();

            Log.e(TAG, "13 - responseCode : " + responseCode);

            if (responseCode == HttpsURLConnection.HTTP_OK) {
                Log.e(TAG, "14 - HTTP_OK");

                String line;
                BufferedReader br = new BufferedReader(new InputStreamReader(
                        conn.getInputStream()));
                while ((line = br.readLine()) != null) {
                    response += line;
                }
            } else {
                Log.e(TAG, "14 - False - HTTP_OK");
                response = "";
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        return response;
    }
}

---

UPDATE 24/08/2016

Use some best library , such as :

• Retrofit
• Volley

because :

• Avoid HttpUrlConnection and HttpClient

On lower API levels (mostly on Gingerbread and Froyo), HttpUrlConnection and HttpClient are far from being perfect

• And Avoid AsyncTask Too
• They are Much Faster
• They Caches Everything

Since the introduction of Honeycomb (API 11), it's been mandatory to perform network operations on a separate thread, different from the main thread

By this way we can send data with http post method and get result

     public class MyHttpPostProjectActivity extends Activity implements OnClickListener {

	private EditText usernameEditText;
	private EditText passwordEditText;
	private Button sendPostReqButton;
	private Button clearButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        usernameEditText = (EditText) findViewById(R.id.login_username_editText);
        passwordEditText = (EditText) findViewById(R.id.login_password_editText);

        sendPostReqButton = (Button) findViewById(R.id.login_sendPostReq_button);
        sendPostReqButton.setOnClickListener(this);

        clearButton = (Button) findViewById(R.id.login_clear_button);
        clearButton.setOnClickListener(this);        
    }

	@Override
	public void onClick(View v) {

		if(v.getId() == R.id.login_clear_button){
			usernameEditText.setText("");
			passwordEditText.setText("");
			passwordEditText.setCursorVisible(false);
			passwordEditText.setFocusable(false);
			usernameEditText.setCursorVisible(true);
			passwordEditText.setFocusable(true);
		}else if(v.getId() == R.id.login_sendPostReq_button){
			String givenUsername = usernameEditText.getEditableText().toString();
			String givenPassword = passwordEditText.getEditableText().toString();

			System.out.println("Given username :" + givenUsername + " Given password :" + givenPassword);

			sendPostRequest(givenUsername, givenPassword);
		}	
	}

	private void sendPostRequest(String givenUsername, String givenPassword) {

		class SendPostReqAsyncTask extends AsyncTask<String, Void, String>{

			@Override
			protected String doInBackground(String... params) {

				String paramUsername = params[0];
				String paramPassword = params[1];

				System.out.println("*** doInBackground ** paramUsername " + paramUsername + " paramPassword :" + paramPassword);

				HttpClient httpClient = new DefaultHttpClient();

				// In a POST request, we don't pass the values in the URL.
				//Therefore we use only the web page URL as the parameter of the HttpPost argument
				HttpPost httpPost = new HttpPost("http://www.nirmana.lk/hec/android/postLogin.php");

				// Because we are not passing values over the URL, we should have a mechanism to pass the values that can be
				//uniquely separate by the other end.
				//To achieve that we use BasicNameValuePair				
				//Things we need to pass with the POST request
				BasicNameValuePair usernameBasicNameValuePair = new BasicNameValuePair("paramUsername", paramUsername);
				BasicNameValuePair passwordBasicNameValuePAir = new BasicNameValuePair("paramPassword", paramPassword);

				// We add the content that we want to pass with the POST request to as name-value pairs
				//Now we put those sending details to an ArrayList with type safe of NameValuePair
				List<NameValuePair> nameValuePairList = new ArrayList<NameValuePair>();
				nameValuePairList.add(usernameBasicNameValuePair);
				nameValuePairList.add(passwordBasicNameValuePAir);

				try {
					// UrlEncodedFormEntity is an entity composed of a list of url-encoded pairs. 
					//This is typically useful while sending an HTTP POST request. 
					UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairList);

					// setEntity() hands the entity (here it is urlEncodedFormEntity) to the request.
					httpPost.setEntity(urlEncodedFormEntity);

					try {
						// HttpResponse is an interface just like HttpPost.
						//Therefore we can't initialize them
						HttpResponse httpResponse = httpClient.execute(httpPost);

						// According to the JAVA API, InputStream constructor do nothing. 
						//So we can't initialize InputStream although it is not an interface
						InputStream inputStream = httpResponse.getEntity().getContent();

						InputStreamReader inputStreamReader = new InputStreamReader(inputStream);

						BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

						StringBuilder stringBuilder = new StringBuilder();

						String bufferedStrChunk = null;

						while((bufferedStrChunk = bufferedReader.readLine()) != null){
							stringBuilder.append(bufferedStrChunk);
						}

						return stringBuilder.toString();

					} catch (ClientProtocolException cpe) {
						System.out.println("First Exception caz of HttpResponese :" + cpe);
						cpe.printStackTrace();
					} catch (IOException ioe) {
						System.out.println("Second Exception caz of HttpResponse :" + ioe);
						ioe.printStackTrace();
					}

				} catch (UnsupportedEncodingException uee) {
					System.out.println("An Exception given because of UrlEncodedFormEntity argument :" + uee);
					uee.printStackTrace();
				}

				return null;
			}

			@Override
			protected void onPostExecute(String result) {
				super.onPostExecute(result);

				if(result.equals("working")){
					Toast.makeText(getApplicationContext(), "HTTP POST is working...", Toast.LENGTH_LONG).show();
				}else{
					Toast.makeText(getApplicationContext(), "Invalid POST req...", Toast.LENGTH_LONG).show();
				}
			}			
		}

		SendPostReqAsyncTask sendPostReqAsyncTask = new SendPostReqAsyncTask();
		sendPostReqAsyncTask.execute(givenUsername, givenPassword);		
	}
}

This is an example of how to POST multi-part data WITHOUT using external Apache libraries:

byte[] buffer = getBuffer();

if(buffer.length > 0) {
   String lineEnd = "\r\n"; 
   String twoHyphens = "--"; 
   String boundary =  "RQdzAAihJq7Xp1kjraqf"; 

   ByteArrayOutputStream baos = new ByteArrayOutputStream();
   DataOutputStream dos = new DataOutputStream(baos);

   // Send parameter #1
   dos.writeBytes(twoHyphens + boundary + lineEnd); 
   dos.writeBytes("Content-Disposition: form-data; name=\"param1\"" + lineEnd);
   dos.writeBytes("Content-Type: text/plain; charset=US-ASCII" + lineEnd);
   dos.writeBytes("Content-Transfer-Encoding: 8bit" + lineEnd);
   dos.writeBytes(lineEnd);
   dos.writeBytes(myStringData + lineEnd);

   // Send parameter #2
   //dos.writeBytes(twoHyphens + boundary + lineEnd); 
   //dos.writeBytes("Content-Disposition: form-data; name=\"param2\"" + lineEnd + lineEnd);
   //dos.writeBytes("foo2" + lineEnd);

   // Send a binary file
   dos.writeBytes(twoHyphens + boundary + lineEnd); 
   dos.writeBytes("Content-Disposition: form-data; name=\"param3\";filename=\"test_file.dat\"" + lineEnd); 
   dos.writeBytes("Content-Type: application/octet-stream" + lineEnd);
   dos.writeBytes("Content-Transfer-Encoding: binary" + lineEnd);
   dos.writeBytes(lineEnd); 
   dos.write(buffer);
   dos.writeBytes(lineEnd); 
   dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd); 
   dos.flush(); 
   dos.close();
				  
   ByteArrayInputStream content = new ByteArrayInputStream(baos.toByteArray());
   BasicHttpEntity entity = new BasicHttpEntity();
   entity.setContent(content);
         
   HttpPost httpPost = new HttpPost(myURL);
   httpPost.addHeader("Connection", "Keep-Alive");
   httpPost.addHeader("Content-Type", "multipart/form-data; boundary="+boundary);
          
   //MultipartEntity entity = new MultipartEntity();
   //entity.addPart("param3", new ByteArrayBody(buffer, "test_file.dat"));
   //entity.addPart("param1", new StringBody(myStringData));
          
   httpPost.setEntity(entity);
          
   /*
   String httpData = "";
   ByteArrayOutputStream baos1 = new ByteArrayOutputStream();
   entity.writeTo(baos1);
   httpData = baos1.toString("UTF-8");
   */

   /*
   Header[] hdrs = httpPost.getAllHeaders();
   for(Header hdr: hdrs) {
     httpData += hdr.getName() + " | " + hdr.getValue() + " |_| ";
   }
   */
          
   //Log.e(TAG, "httpPost data: " + httpData);
   response = httpClient.execute(httpPost);
}

to @primpop answer I would add how to convert the response in a String:

HttpResponse response = client.execute(request);
HttpEntity entity = response.getEntity();
if (entity != null) {
    InputStream instream = entity.getContent();

    String result = RestClient.convertStreamToString(instream);
    Log.i("Read from server", result);
}

Here is an example of convertStramToString.

You can use the following to send an HTTP-POST request to a URL and receive the response. I always use this:

try {
    AsyncHttpClient client = new AsyncHttpClient();
    // Http Request Params Object
    RequestParams params = new RequestParams();
    String u = "B2mGaME";
    String au = "gamewrapperB2M";
    // String mob = "880xxxxxxxxxx";
    params.put("usr", u.toString());
    params.put("aut", au.toString());
    params.put("uph", MobileNo.toString());
    //  params.put("uph", mob.toString());
    client.post("http://196.6.13.01:88/ws/game_wrapper_reg_check.php", params, new AsyncHttpResponseHandler() {
        @Override
        public void onSuccess(String response) {
            playStatus = response;
            //////Get your Response/////
            Log.i(getClass().getSimpleName(), "Response SP Status. " + playStatus);
        }
        @Override
        public void onFailure(Throwable throwable) {
            super.onFailure(throwable);
        }
    });
} catch (Exception e) {
    e.printStackTrace();
}

You Also need to Add bellow Jar file in libs folder

android-async-http-1.3.1.jar

Finally, I have edit your build.gradle:

dependencies {
    compile files('libs/<android-async-http-1.3.1.jar>')
}

In the last Rebuild your project.

Better use Apache Commons HttpClient, that is also included in android already. Have a look at Android Developer: Apache HTTP Client Package Summary for general api info.

Use the open source okHttp library from Square. okHttp works from Android 2.3 and up and has an Apache 2.0 license on GitHub.

Sending POST data is as simple as adding the following in an AsyncTask:

OkHttpClient client = new OkHttpClient();
RequestBody formBody = new FormBody.Builder()
                      .add("email", emailString) // A sample POST field
                      .add("comment", commentString) // Another sample POST field
                      .build();
Request request = new Request.Builder()
                 .url("https://yourdomain.org/callback.php") // The URL to send the data to
                 .post(formBody)
                 .build();

okHttp also has a namespace on maven, so adding it to your Android Studio project is simple. Just add compile 'com.squareup.okhttp3:okhttp:3.11.0' to your app's build.gradle.

Complete Code

Add the following to your activity:

public class CallAPI extends AsyncTask<String, String, String> {

    String emailString;
    String commentString;

    public CallAPI(String email, String commnt){
           emailString = email;
           commentString = commnt;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(String... params) {
        OkHttpClient client = new OkHttpClient();
        RequestBody formBody = new FormBody.Builder()
                      .add("email", emailString) // A sample POST field
                      .add("comment", commentString) // Another sample POST field
                      .build();
        Request request = new Request.Builder()
                 .url("https://yourdomain.org/callback.php") // The URL to send the data to
                 .post(formBody)
                 .build();
        return "";
    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
    }
}

And call it using:

new CallAPI(emailString, commentString).execute();

You can use URLConnection with setDoOutput(true), getOutputStream() (for sending data), and getInputStream() (for receiving). Sun has an example for exactly this.

For me works next :

 private sendData() {
     JSONObject jsonObject = new JSONObject();
     jsonObject.accumulate("key1", value1);
     jsonObject.accumulate("key2", value2);

     boolean success = sendPost(SERVER_URL + "/v1/auth", jsonObject);
 }

 private boolean sendPost(String url, JSONObject parameters) {
        boolean requestResult = false;
        InputStream inputStream = null;
        String result = "";
        try {

            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);

            String json = "";

            json = parameters.toString();

            StringEntity se = new StringEntity(json);
            httpPost.setEntity(se);

            httpPost.setHeader("Accept", "application/json");
            httpPost.setHeader("Content-type", "application/json");

            HttpResponse httpResponse = httpclient.execute(httpPost);

            inputStream = httpResponse.getEntity().getContent();

            if (inputStream != null) {
                result = convertInputStreamToString(inputStream);
                requestResult = true;
            } else {
                result = "Did not work!";
                requestResult = false;
            }
            System.out.println(result);
        } catch (Exception e) {
            Log.d("InputStream", e.getLocalizedMessage());
            requestResult = false;
        }
        return requestResult;
    }

If you just want to append data to the Url You can do so by using HttpUrlConnection since HttpClient is now deprecated. A better way would be to use a library like-

Volley Retrofit

We can post data to the php script and fetch result and display it by using this code performed Through AsyncTask class.

    private class LongOperation  extends AsyncTask<String, Void, Void> {

    // Required initialization


    private String Content;
    private String Error = null;
    private ProgressDialog Dialog = new ProgressDialog(Login.this);
    String data ="";
    int sizeData = 0;



    protected void onPreExecute() {
        // NOTE: You can call UI Element here.

        //Start Progress Dialog (Message)

        Dialog.setMessage("Please wait..");
        Dialog.show();
        Dialog.setCancelable(false);
        Dialog.setCanceledOnTouchOutside(false);

        try{
            // Set Request parameter
            data +="&" + URLEncoder.encode("username", "UTF-8") + "="+edittext.getText();
          
          

        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    // Call after onPreExecute method
    protected Void doInBackground(String... urls) {

        /************ Make Post Call To Web Server ***********/
        BufferedReader reader=null;

        // Send data
        try
        {

            // Defined URL  where to send data
            URL url = new URL(urls[0]);

            // Send POST data request

            URLConnection conn = url.openConnection();
            
            conn.setConnectTimeout(5000);//define connection timeout 
            conn.setReadTimeout(5000);//define read timeout
            conn.setDoOutput(true);
            OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
            wr.write( data );
            wr.flush();

            // Get the server response

            reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            StringBuilder sb = new StringBuilder();
            String line = null;



            // Read Server Response
            while((line = reader.readLine()) != null)
            {
                // Append server response in string
                sb.append(line + " ");
            }

            // Append Server Response To Content String
            Content = sb.toString();

           
        }
        catch(Exception ex)
        {
            Error = ex.getMessage();
        }
        finally
        {
            try
            {

                reader.close();
            }

            catch(Exception ex) {}
        }

       
        return null;
    }

    protected void onPostExecute(Void unused) {
        // NOTE: You can call UI Element here.

        // Close progress dialog
        Dialog.dismiss();
        
        if (Error != null) {

                Toast.makeText(getApplicationContext(),"Error encountered",Toast.LENGTH_LONG).show();

            

        }
        else {




            try {

                JSONObject jsonRootObject = new JSONObject(Content);


                JSONObject json2 =jsonRootObject.getJSONObject("jsonkey");//pass jsonkey here


                String id =json2.optString("id").toString();//parse json to string through parameters

               
     //the result is stored in string id. you can display it now
               
               
            } catch (JSONException e) {e.printStackTrace();}


        }

    }

}

But using libraries such as volley or retrofit is much better option because Asynctask class and HttpurlConnection is slower compared to libraries. Also the library will fetch everything and is faster as well.

I found this helpful example with this video tutorial.

>Connector Class:

package com.tutorials.hp.mysqlinsert;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel.
 */
public class Connector {
    /*
 1.SHALL HELP US ESTABLISH A CONNECTION TO THE NETWORK
 2. WE ARE MAKING A POST REQUEST
  */
    public static HttpURLConnection connect(String urlAddress) {
        try
        {
            URL url=new URL(urlAddress);
            HttpURLConnection con= (HttpURLConnection) url.openConnection();
            //SET PROPERTIES
            con.setRequestMethod("POST");
            con.setConnectTimeout(20000);
            con.setReadTimeout(20000);
            con.setDoInput(true);
            con.setDoOutput(true);
            //RETURN
            return con;
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
 }

---

> DataPackager Class:

package com.tutorials.hp.mysqlinsert;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.Iterator;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel.
 * 1.BASICALLY PACKS DATA WE WANNA SEND
 */
public class DataPackager {
    String name,position,team;
    /*
    SECTION 1.RECEIVE ALL DATA WE WANNA SEND
     */
    public DataPackager(String name, String position, String team) {
        this.name = name;
        this.position = position;
        this.team = team;
    }
    /*
   SECTION 2
   1.PACK THEM INTO A JSON OBJECT
   2. READ ALL THIS DATA AND ENCODE IT INTO A FROMAT THAT CAN BE SENT VIA NETWORK
    */
    public String packData()
    {
        JSONObject jo=new JSONObject();
        StringBuffer packedData=new StringBuffer();
        try
        {
            jo.put("Name",name);
            jo.put("Position",position);
            jo.put("Team",team);
            Boolean firstValue=true;
            Iterator it=jo.keys();
            do {
                String key=it.next().toString();
                String value=jo.get(key).toString();
                if(firstValue)
                {
                    firstValue=false;
                }else
                {
                    packedData.append("&");
                }
                packedData.append(URLEncoder.encode(key,"UTF-8"));
                packedData.append("=");
                packedData.append(URLEncoder.encode(value,"UTF-8"));
            }while (it.hasNext());
            return packedData.toString();
        } catch (JSONException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
        }
}

---

> Sender Class:

package com.tutorials.hp.mysqlinsert;
import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.widget.EditText;
import android.widget.Toast;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel and Camposha.com.
 * 1.SEND DATA FROM EDITTEXT OVER THE NETWORK
 * 2.DO IT IN BACKGROUND THREAD
 * 3.READ RESPONSE FROM A SERVER
 */
public class Sender extends AsyncTask<Void,Void,String> {
    Context c;
    String urlAddress;
    EditText nameTxt,posTxt,teamTxt;
    String name,pos,team;
    ProgressDialog pd;
    /*
            1.OUR CONSTRUCTOR
    2.RECEIVE CONTEXT,URL ADDRESS AND EDITTEXTS FROM OUR MAINACTIVITY
    */
    public Sender(Context c, String urlAddress,EditText...editTexts) {
        this.c = c;
        this.urlAddress = urlAddress;
        //INPUT EDITTEXTS
        this.nameTxt=editTexts[0];
        this.posTxt=editTexts[1];
        this.teamTxt=editTexts[2];
        //GET TEXTS FROM EDITEXTS
        name=nameTxt.getText().toString();
        pos=posTxt.getText().toString();
        team=teamTxt.getText().toString();
    }
    /*
   1.SHOW PROGRESS DIALOG WHILE DOWNLOADING DATA
    */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pd=new ProgressDialog(c);
        pd.setTitle("Send");
        pd.setMessage("Sending..Please wait");
        pd.show();
    }
    /*
    1.WHERE WE SEND DATA TO NETWORK
    2.RETURNS FOR US A STRING
     */
    @Override
    protected String doInBackground(Void... params) {
        return this.send();
    }
    /*
  1. CALLED WHEN JOB IS OVER
  2. WE DISMISS OUR PD
  3.RECEIVE A STRING FROM DOINBACKGROUND
   */
    @Override
    protected void onPostExecute(String response) {
        super.onPostExecute(response);
        pd.dismiss();
        if(response != null)
        {
            //SUCCESS
            Toast.makeText(c,response,Toast.LENGTH_LONG).show();
            nameTxt.setText("");
            posTxt.setText("");
            teamTxt.setText("");
        }else
        {
            //NO SUCCESS
            Toast.makeText(c,"Unsuccessful "+response,Toast.LENGTH_LONG).show();
        }
    }
/*
SEND DATA OVER THE NETWORK
RECEIVE AND RETURN A RESPONSE
 */
    private String send()
    {
        //CONNECT
        HttpURLConnection con=Connector.connect(urlAddress);
        if(con==null)
        {
            return null;
        }
        try
        {
            OutputStream os=con.getOutputStream();
            //WRITE
            BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(os,"UTF-8"));
            bw.write(new DataPackager(name,pos,team).packData());
            bw.flush();
            //RELEASE RES
            bw.close();
            os.close();
            //HAS IT BEEN SUCCESSFUL?
            int responseCode=con.getResponseCode();
            if(responseCode==con.HTTP_OK)
            {
                //GET EXACT RESPONSE
                BufferedReader br=new BufferedReader(new InputStreamReader(con.getInputStream()));
                StringBuffer response=new StringBuffer();
                String line;
                //READ LINE BY LINE
                while ((line=br.readLine()) != null)
                {
                    response.append(line);
                }
                //RELEASE RES
                br.close();
                return response.toString();
            }else
            {
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
}

---

> MainActivity:

package com.tutorials.hp.mysqlinsert;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
/*
1.OUR LAUNCHER ACTIVITY
2.INITIALIZE SOME UI STUFF
3.WE START SENDER ON BUTTON CLICK
 */
public class MainActivity extends AppCompatActivity {
    String urlAddress="http://10.0.2.2/android/poster.php";
    EditText nameTxt,posTxt,teamTxt;
    Button saveBtn;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        //INITIALIZE UI FIELDS
        nameTxt= (EditText) findViewById(R.id.nameEditTxt);
        posTxt= (EditText) findViewById(R.id.posEditTxt);
        teamTxt= (EditText) findViewById(R.id.teamEditTxt);
        saveBtn= (Button) findViewById(R.id.saveBtn);
        saveBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //START ASYNC TASK
                Sender s=new Sender(MainActivity.this,urlAddress,nameTxt,posTxt,teamTxt);
                s.execute();
            }
        });
    }
}

> ContentMain.xml:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.tutorials.hp.mysqlinsert.MainActivity"
    tools:showIn="@layout/activity_main">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!" />
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="?attr/actionBarSize"
        android:orientation="vertical"
        android:paddingLeft="15dp"
        android:paddingRight="15dp"
        android:paddingTop="50dp">
        <android.support.design.widget.TextInputLayout
            android:id="@+id/nameLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/nameEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:singleLine="true"
                android:hint= "Name" />
        </android.support.design.widget.TextInputLayout>
        <android.support.design.widget.TextInputLayout
            android:id="@+id/teamLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/teamEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Description" />
        </android.support.design.widget.TextInputLayout>
        <android.support.design.widget.TextInputLayout
            android:id="@+id/posLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/posEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Position" />
            <!--android:inputType="textPassword"-->
        </android.support.design.widget.TextInputLayout>
        <Button android:id="@+id/saveBtn"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Save"
            android:clickable="true"
            android:background="@color/colorAccent"
            android:layout_marginTop="40dp"
            android:textColor="@android:color/white"/>
    </LinearLayout>
</RelativeLayout>

Method to post data as HTTP request,

public static InputStream callPostService(String Url,
		List<NameValuePair> data) {
	HttpClient httpclient = new DefaultHttpClient();
	HttpPost httppost = new HttpPost(Url);
	try {
		httppost.setEntity(new UrlEncodedFormEntity(data));
		HttpResponse response = httpclient.execute(httppost);
		HttpEntity entity = response.getEntity();
		return entity.getContent();
	} catch (ClientProtocolException e) {
		e.printStackTrace();
	} catch (IOException e) {
		e.printStackTrace();
	}
	return null;
}

You can POST an HttpRequest using WebServer class and track the response in its listener interface.

WebServer server=new WebServer(getApplicationContext());
		
server.setOnServerStatusListner(new WebServer.OnServerStatusListner() {
	@Override
	public void onServerResponded(String responce) {
		
	}

	@Override
	public void onServerRevoked() {

	}
});

Now create a DataRack to bind your data

List<DataRack> racks=new ArrayList<DataRack>();
racks.add(new DataRack("name","Simon"));
racks.add(new DataRack("age","40"));
racks.add(new DataRack("location","Canada"));

Now simply send the POST request with that rack

server.connectWithPOST(MainActivity.this,"http://sangeethnandakumar.esy.es/PROJECTS/PUBLIC_SERVICE/posttest.php",racks);

You need to include my library for this. Documentations here

In newer versions of Android you have to put all web I/O requests into a new thread. AsyncTask works best for small requests.

The below method works with latest Android Libraries and using okhttp.

    OkHttpClient client = new OkHttpClient();
    RequestBody formBody = new FormBody.Builder()
            .add("key1", "value1")
            .add("key2", "value2")  //optional
            .add("key3", "value3")  //optional
            .add("key4", "value4")  //optional
            .build();


    Request request = new Request.Builder()
    .url("http://.....")   //URL
    .post(formBody)
    .build();


    client.newCall(request).enqueue(new Callback() {
        @Override
        public void onFailure(@NonNull Call call, @NonNull IOException e) {
            e.getStackTrace();
        }

        @Override
       public void onResponse(@NonNull Call call, @NonNull Response response) throws IOException {
            if(response.isSuccessful()){
                ResponseBody responseBody = response.body();
                Log.e("TAG_", responseBody.string());
       }
    }