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Listen to JComboBox with ItemListener

You can listen with an ActionListener or an ItemListener to find out when the selected item of the JComboBox changes. import java.awt.BorderLayout; import java.awt.ItemSelectable; import java.awt.event.ItemEvent; import java.awt.event.ItemListener; import javax.swing.JComboBox; import javax.swing.JFrame; public class ItemListenerSelectingComboSample {   static private String selectedString(ItemSelectable is) {     Object selected[] = is.getSelectedObjects();     return ((selected.length == 0) ? "null" : (String) selected[0]);   }   public static void main(String args[]) {     String labels[] = { "A", "B", "C", "D", "E", "F" };     JFrame frame = new JFrame("Selecting JComboBox");     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     JComboBox comboBox = new JComboBox(labels);     frame.add(comboBox, BorderLayout.SOUTH);     ItemListener itemListener = new ItemListener() {       public void itemStateChanged(ItemEvent itemEvent) {         int state = itemEvent.getStateChange();         System.out.println((state == ItemEvent.SELECTED) ? "Selected" : "Deselected");         System.out.println("Item: " + itemEvent.getItem());         ItemSelectable is = itemEvent.getItemSelectable();         System.out.println(", Selected: " + selectedString(is));       }     };     comboBox.addItemListener(itemListener);     frame.setSize(400, 200);     frame.setVisible(true);   } }