Creating Action Listeners for JButtons in Java

When developing graphical user interfaces (GUIs) in Java, adding action listeners to buttons enables them to respond to user clicks and trigger specific actions within the program. Here's how to implement this functionality using two different methods:

1. Implements ActionListener Interface:

• Define a class that implements the ActionListener interface.
• For each button, use the addActionListener() method to register the class object as the action listener:

JButton jBtnSelection = new JButton("Selection");
jBtnSelection.addActionListener(this);

• Implement the actionPerformed(ActionEvent e) method in the class to handle button-click events.

2. Anonymous Inner Classes:

For each button, create an anonymous inner class that extends ActionListener and implements the actionPerformed(ActionEvent e) method to handle button clicks:

jBtnSelection.addActionListener(new ActionListener() {
  @Override
  public void actionPerformed(ActionEvent e) {
    selectionButtonPressed();
  }
} );

• Define the corresponding selectionButtonPressed() method to perform the desired action when the button is clicked.

2. Updated (Java 8 Lambda Expressions):

Using lambda expressions introduced in Java 8, you can simplify the anonymous inner class approach:

jBtnSelection.addActionListener(e -> selectionButtonPressed());

This lambda expression directly calls the selectionButtonPressed() method when the button is clicked, avoiding the need for an anonymous inner class.