Listening for Changes to the Selection in a JList Component : JList Selection « Swing « Java Tutorial

1. Java Tutorial
2. Swing
3. JList Selection

import javax.swing.JList;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class Main {
  public static void main(String[] argv) throws Exception {
    String[] items = { "A", "B", "C", "D" };
    JList list = new JList(items);
    list.addListSelectionListener(new MyListSelectionListener());
  }
}

class MyListSelectionListener implements ListSelectionListener {
  public void valueChanged(ListSelectionEvent evt) {
    if (!evt.getValueIsAdjusting()) {
      JList list = (JList) evt.getSource();
      Object[] selected = list.getSelectedValues();

      for (int i = 0; i < selected.length; i++) {
        Object sel = selected[i];
      }
    }
  }
}