How to Send Free SMS in java using SMS API? [With Source Code]

Watch the Designing part in Video:

       
  // import package
  import java.io.BufferedReader;
  import java.io.InputStreamReader;
  import java.io.OutputStreamWriter;
  import java.net.URL;
  import java.net.URLConnection;
  import java.net.URLEncoder;
  import java.net.HttpURLConnection;
  import javax.swing.JOptionPane;

               try {
   // Construct data
   String apiKey = "apikey=" + txtapi.getText();
   String message = "&message=" + txtmess.getText();
   String sender = "&sender=" + txtsender.getText();
   String numbers = "&numbers=" + txtnumber.getText();
   
   // Send data
   HttpURLConnection conn = (HttpURLConnection) new URL("https://api.txtlocal.com/send/?").openConnection();
   String data = apiKey + numbers + message + sender;
   conn.setDoOutput(true);
   conn.setRequestMethod("POST");
   conn.setRequestProperty("Content-Length", Integer.toString(data.length()));
   conn.getOutputStream().write(data.getBytes("UTF-8"));
   final BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
   final StringBuffer stringBuffer = new StringBuffer();
   String line;
   while ((line = rd.readLine()) != null) {
    //stringBuffer.append(line);
                                JOptionPane.showMessageDialog(null, "message"+line);
   }
   rd.close();
   
   //return stringBuffer.toString();
  } catch (Exception e) {
   //System.out.println("Error SMS "+e);
                        JOptionPane.showMessageDialog(null, e);
   //return "Error "+e;

       
 

Video: