import java.awt.ItemSelectable;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.event.EventListenerList;
public class Main {
public static void main(String[] argv) throws Exception {
MyComponent component = new MyComponent();
JFrame f = new JFrame();
f.add(component);
f.setSize(300, 300);
f.setVisible(true);
}
}
class MyComponent extends JTextField implements ItemSelectable {
protected EventListenerList listenerList = new EventListenerList();
public Object[] getSelectedObjects() {
return new String[] { "a", "b", "c" };
}
public void addItemListener(ItemListener l) {
listenerList.add(ItemListener.class, l);
}
public void removeItemListener(ItemListener l) {
listenerList.remove(ItemListener.class, l);
}
void fireItemEvent(Object item, boolean sel) {
ItemEvent evt = new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, item,
sel ? ItemEvent.SELECTED : ItemEvent.DESELECTED);
Object[] listeners = listenerList.getListenerList();
for (int i = 0; i < listeners.length - 2; i += 2) {
if (listeners[i] == ItemListener.class) {
((ItemListener) listeners[i + 1]).itemStateChanged(evt);
}
}
}
}
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