Friday Java Quiz: What Will The GUI Show?

1    import javax.swing.*; 
2    import java.awt.*; 
3    import java.awt.event.*; 
4     
5    public class Foo { 
6        public static void main(final String[] args) { 
7            EventQueue.invokeLater(new Runnable() { 
8                public void run() { 
9                    swingMain(); 
10               } 
11           }); 
12       } 
13    
14       private static void swingMain() { 
15           JFrame frame = new JFrame("Demo"); 
16           frame.setLayout(new FlowLayout()); 
17    
18           JTextField tf1 = new JTextField(20); 
19           final JTextField tf2 = new JTextField(20); 
20           JButton b = new JButton("Click Me"); 
21    
22           tf1.addFocusListener(new FocusAdapter() { 
23               @Override 
24               public void focusLost(FocusEvent e) { 
25                   tf2.setText("Lost Focus!"); 
26               } 
27           }); 
28    
29           b.addActionListener(new ActionListener() { 
30               public void actionPerformed(ActionEvent e) { 
31                   tf2.setText("Clicked!"); 
32               } 
33           }); 
34    
35           frame.add(tf1); 
36           frame.add(tf2); 
37           frame.add(b); 
38           frame.pack(); 
39           frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); 
40           frame.setVisible(true); 
41       } 
42   }

Q: If, after starting the above Swing program, you click on the JButton b, what will the JTextField jt2 show?
Lost Focus!
or
Clicked!

Strict rule apply: no compiling and running, no Googling, and your first answer is the final answer. You are allowed to read the Javadoc of the relevant classes though.

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Posted by Weiqi Gao on July 2, 2010 7:12:55 AM CDT #