Which listener should I use for JTextField?

Question

In my logo quiz game I have to take the value written in text Field when the user press ENTER key and compare it with the correct answer.Which listener should I use. I used Action listener but it's not working. I am new to programming.

 private JTextField textField=new JTextField("");
 textField.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            result();
        }
    });

    textField.setBounds(0, 241, 264, 31);
    getContentPane().add(textField);
    textField.setColumns(10);


  private void result(){

    answer=textField.getText();

    if(answer=="apple"){
        JOptionPane.showMessageDialog(this, "right answer");
    }
    else{
        JOptionPane.showMessageDialog(this, "wrong answer");
    }
}}