Im learning sql for my school project and i have a problem

Logcat:

ViewPostIme pointer 0
ViewPostIme pointer 1
password :password63826  username:tesr1234
Communications link failure //The Problem
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

code:

        password = findViewById(R.id.Password);
        username = findViewById(R.id.Username);
        button = findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            String user1, pass1;

            user1 = username.getText().toString();
            pass1 = password.getText().toString();
                System.out.println("password :"+pass1+"  username:"+user1);


                String url = "jdbc:mysql://localhost:3306/KonradServer";

                String user = "root";
                String pass = "Konrad99";

                try {
                    // Verbindung aufbauen
                    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
                    StrictMode.setThreadPolicy(policy);
                    Connection con = DriverManager.getConnection(url, user, pass);
                    System.out.println("Verbindung erfolgreich hergestellt");
                } catch (SQLException e) {
                    System.out.println(e.getMessage());
                }

            }//onclick
        });//onclick

I do it on local server just downloaded MySQL Server and Workshop.

SQL connector:

 implementation(libs.mysql.connector.java)

Press Button
save Edittext input in Strings
Test Database connection