import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

class Main implements ActionListener{
	
	public static void main(String args[]){
		Main main = new Main();
	}
	
	public Main(){
		JFrame frame = new JFrame();
		JPanel panel = new JPanel();
		
		JButton button1 = new JButton();
		button1.setText("Button 1");
		button1.addActionListener(this);
		
		JButton button2 = new JButton();
		button2.setText("Button 2");
		button2.addActionListener(this);
		
		panel.add(button1);
		panel.add(button2);
		
		frame.getContentPane().add(panel);
		
		frame.setSize(200,200);
		frame.setVisible(true);
	}
	
	public void actionPerformed(ActionEvent e){
		switch(e.getActionCommand()){
			case "Button 1":
				System.out.println("You clicked Button 1");
				break;
			case "Button 2":
				System.out.println("You clicked Button 2");
				break;
		}
	}
}

http://www.snippetcentral.net/java/multiple-jbuttons-with-a-single-actionlistener.html

This code snippet shows how to handle multiple JButtons with a single ActionListener.

Multiple JButtons With A Single ActionListener

Java