Make "Enter" trigger an action

Question

I have a login screen to a system and I want that when the user has a selected button, when pressing "Enter" on the keyboard, the button triggers its action. Ex.:

• if the confirm button is selected and enter is activated log in
• if the cancel button is selected and enter is activated close the screen

Follow the code of the ready screen:

public class loginPopup implements ActionListener
{
    private JFrame ourFrame = new JFrame("Login");

    JTextField user_text = new JTextField();
    JPasswordField pass_text = new JPasswordField();
    JDateChooser calendario = new JDateChooser();

    JButton yesButton = new JButton("Confirmar");
    JButton noButton = new JButton("Cancelar");

    public loginPopup()
    {
        ourFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        ourFrame.setBounds(600, 300, 400, 250);

        Container container = ourFrame.getContentPane();
        container.setLayout(null);

        JLabel logo = new JLabel("INSIRA SEUS DADOS DO SISTEMA");
        logo.setBounds(105, 5, 250, 30);

        JLabel user_label = new JLabel("Usuário:");
        user_label.setBounds(20, 40, 250, 30);

        JLabel pass_label = new JLabel("Senha:");
        pass_label.setBounds(20, 80, 250, 30);


        user_text.setBounds(70, 45, 250, 20);       
        pass_text.setBounds(70, 85, 250, 20);


        calendario.setBounds(90, 120, 210, 25);


        yesButton.setBounds(70, 165, 100, 30);
        yesButton.addActionListener(this);

        noButton.setBounds(210, 165, 100, 30);
        noButton.addActionListener(this);

        container.add(logo);
        container.add(user_label);
        container.add(pass_label);
        container.add(user_text);
        container.add(pass_text);
        container.add(calendario);
        container.add(yesButton);
        container.add(noButton);
        ourFrame.setVisible(true);
    }

        @SuppressWarnings("deprecation")
        public void actionPerformed(ActionEvent e)
        {
            if (e.getSource() == yesButton)
        {
            String user = user_text.getText();
            String pass = pass_text.getText();
            Date oldDate = calendario.getDate();

            //CODIGO DA AÇÃO EX.:
            System.out.println("Confirmar!");
        }
        else if (e.getSource() == noButton)
        {
            System.exit(0);
        }

    }

    public static void main(String[] args)
    {   
        new loginPopup();
    }
}

Now I need to add the "Enter" part but I can’t do it