Java Swing How to - Get selected value when selection changed

Question

We would like to know how to get selected value when selection changed.

Answer

import java.awt.BorderLayout;
import java.util.Arrays;
/*from   w ww . ja  v  a 2 s  .  c o m*/
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class Main extends JPanel {

  JList list;
  public Main() {
    super(new BorderLayout());
    String[] data = { "Math", "Computer", "Physics", "Chemistry" };
    list = new JList(data);
    list.addListSelectionListener(new SelectionHandler());
    JScrollPane jsp = new JScrollPane(list);
    this.add(jsp, BorderLayout.CENTER);
  }

  private class SelectionHandler implements ListSelectionListener {
    @Override
    public void valueChanged(ListSelectionEvent e) {
      if (!e.getValueIsAdjusting()) {
        System.out.println(Arrays.toString(list.getSelectedValues()));
      }
    }
  }

  public static void main(String[] args) {
    JFrame f = new JFrame("ListPanel");
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.add(new Main());
    f.pack();
    f.setVisible(true);

  }
}