code: package ui;
  
  import java.io.IOException;
  import java.io.ObjectOutputStream;
  import java.net.InetSocketAddress;
  import java.net.Socket;
  
  import static ui.MainActivity.SQLDatabase;
  import static ui.MainActivity.TIMEOUT;
  import static ui.MainActivity.portNumber;
  
  public class test_connection implements Runnable
  {
      boolean connected = false;
      public void run()
      {
          try
          {
              Socket ClientSocket = new Socket();
              ClientSocket.connect(new InetSocketAddress(SQLDatabase, portNumber), TIMEOUT);
              ObjectOutputStream toServer = new ObjectOutputStream(ClientSocket.getOutputStream());
              toServer.writeObject("Hello");
              toServer.flush();
              connected = true;
          }
          catch (IOException e)
          {
              connected = false;
          }
      }
  }
  