C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet>dir Volume in drive C has no label. Volume Serial Number is 2041-64E7 Directory of C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet 2009-07-02 23:54 . 2009-07-02 23:54 .. 2004-09-06 14:57 582 WelcomeApplet.html 2004-09-06 15:04 1,402 WelcomeApplet.java 2 File(s) 1,984 bytes 2 Dir(s) 2,557,210,624 bytes free C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet>javac WelcomeApplet.java C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet>dir Volume in drive C has no label. Volume Serial Number is 2041-64E7 Directory of C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet 2009-07-02 23:54 . 2009-07-02 23:54 .. 2009-07-02 23:54 975 WelcomeApplet$1.class 2009-07-02 23:54 1,379 WelcomeApplet.class 2004-09-06 14:57 582 WelcomeApplet.html 2004-09-06 15:04 1,402 WelcomeApplet.java 4 File(s) 4,338 bytes 2 Dir(s) 2,557,202,432 bytes free C:\Program Files\Java\jdk1.6.0_05\CoreJava\v1\v1ch2\WelcomeApplet>
這裏是Java文件的內容:
/**
@version 1.21 2002-06-19
@author Cay Horstmann
*/
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
public class WelcomeApplet extends JApplet
{
public void init()
{
setLayout(new BorderLayout());
JLabel label = new JLabel(getParameter("greeting"), SwingConstants.CENTER);
label.setFont(new Font("Serif", Font.BOLD, 18));
add(label, BorderLayout.CENTER);
JPanel panel = new JPanel();
JButton cayButton = new JButton("Cay Horstmann");
cayButton.addActionListener(makeURLActionListener(
"http://www.horstmann.com"));
panel.add(cayButton);
JButton garyButton = new JButton("Gary Cornell");
garyButton.addActionListener(makeURLActionListener(
"mailto:[email protected]"));
panel.add(garyButton);
add(panel, BorderLayout.SOUTH);
}
private ActionListener makeURLActionListener(final String u)
{
return new
ActionListener()
{
public void actionPerformed(ActionEvent event)
{
try
{
getAppletContext().showDocument(new URL(u));
}
catch(MalformedURLException e)
{
e.printStackTrace();
}
}
};
}
}
但在WelcomeApplet.java文件中沒有內部類,我用文件內容更新。 – omg 2009-07-02 15:59:40
是的,有。它是這樣開始的:return new ActionListener(){public void actionPerformed ... – 2009-07-02 16:05:20
您的applet中有一個內部類,它是您在makeURLActionListener()中創建的ActionListener - Metod是類的內聯定義。你說新的ActionListener()後跟{...}中的類定義,其中你實現了actionPerformed方法 – jitter 2009-07-02 16:05:36