public class CheckLogin extends AsyncTask<String,String,String>
{
    String z = "";
    Boolean isSuccess = false;

    @Override
    protected void onPreExecute()
    {
//            progressBar.setVisibility(View.VISIBLE);
    }

    @Override
    protected void onPostExecute(String r)
    {
//            progressBar.setVisibility(View.GONE);
        Toast.makeText(LoginActivity.this, r, Toast.LENGTH_SHORT).show();
        if(isSuccess)
        {
            Toast.makeText(LoginActivity.this , "Login Successfull" , Toast.LENGTH_LONG).show();
            //finish();
        }
    }

    @Override
    protected String doInBackground(String... params)
    {
        java.sql.Connection con;
        String usernam = params[0];
        String passwordd = params[1];
        if(usernam.trim().equals("")|| passwordd.trim().equals(""))
            z = "Please enter Username and Password";
        else
        {
            try
            {
                con = connectionclass();

                if (con == null)
                {
                    z = "Check Your Internet Access!";
                }
                else
                {
                    // Change below query according to your own database.
                    String query = "select * from owner where mail = '" + usernam.toString() + "' and password = '"+ passwordd.toString() +"'  ";
                    Statement stmt = con.createStatement();
                    ResultSet rs = stmt.executeQuery(query);
                    if(rs.next())
                    {
                        z = "Login successful";
                        isSuccess=true;
                        con.close();
                    }
                    else
                    {
                        z = "Invalid Credentials!";
                        isSuccess = false;
                    }
                }
            }
            catch (Exception ex)
            {
                isSuccess = false;
                z = ex.getMessage();
            }
        }
        return z;
    }
}


@SuppressLint("NewApi")
public java.sql.Connection connectionclass()
{
    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
    StrictMode.setThreadPolicy(policy);
    java.sql.Connection connection = null;
    String ConnectionURL = null;
    try
    {
          Class.forName("com.mysql.jdbc.Driver");

          connection = DriverManager.getConnection(url, un, pas);

    }
    catch (SQLException se)
    {
        Log.e("error here 1 : ", se.getMessage());
    }
    catch (ClassNotFoundException e)
    {
        Log.e("error here 2 : ", e.getMessage());
    }
    catch (Exception e)
    {
        Log.e("error here 3 : ", e.getMessage());
    }
    return connection;
}

jdbc:mysql://185.176.43.41:3306/DB_name