Java by API/java.awt/ActionListener

implements ActionListener

   <source lang="java">

import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JTextField; public class MainClass extends JPanel implements ActionListener {

 JTextField jtf = new JTextField(15);
 public MainClass() {

     add(jtf); 
     jtf.addActionListener(this); 
   } 
  
   // Show text when user presses ENTER. 
   public void actionPerformed(ActionEvent ae) { 
     System.out.println(jtf.getText()); 
   } 
 public static void main(String[] args) {
   JFrame frame = new JFrame();
   frame.getContentPane().add(new MainClass());
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.setSize(200, 200);
   frame.setVisible(true);
 }

}

      </source>