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Listening to JList Events with a ListSelectionListener

If you want to know when elements of a JList have been selected, you need to attach a ListSelectionListener to the JList or the ListSelectionModel. public interface ListSelectionListener extends EventListener {   public void valueChanged(ListSelectionEvent e); } import java.awt.BorderLayout; import javax.swing.JFrame; import javax.swing.JList; import javax.swing.JScrollPane; import javax.swing.event.ListSelectionEvent; import javax.swing.event.ListSelectionListener; public class SelectingJListSample {   public static void main(String args[]) {     String labels[] = { "A", "B", "C", "D", "E", "F", "G", "H" };     JFrame frame = new JFrame("Selecting JList");     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     JList jlist = new JList(labels);     JScrollPane scrollPane1 = new JScrollPane(jlist);     frame.add(scrollPane1, BorderLayout.CENTER);     ListSelectionListener listSelectionListener = new ListSelectionListener() {       public void valueChanged(ListSelectionEvent listSelectionEvent) {         System.out.println("First index: " + listSelectionEvent.getFirstIndex());         System.out.println(", Last index: " + listSelectionEvent.getLastIndex());         boolean adjust = listSelectionEvent.getValueIsAdjusting();         System.out.println(", Adjusting? " + adjust);         if (!adjust) {           JList list = (JList) listSelectionEvent.getSource();           int selections[] = list.getSelectedIndices();           Object selectionValues[] = list.getSelectedValues();           for (int i = 0, n = selections.length; i < n; i++) {             if (i == 0) {               System.out.println(" Selections: ");             }             System.out.println(selections[i] + "/" + selectionValues[i] + " ");           }         }       }     };     jlist.addListSelectionListener(listSelectionListener);     frame.setSize(350, 200);     frame.setVisible(true);   } }