问答题

本题用复选框来控制字体的显示，窗口中有一个标签和两个复选按钮，这两个复选按钮分别对应的字体的两个特点：加粗和倾斜，任意选中一个按钮或两个都选中，标签上的字符串就显示对应的字体。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class CheckBoxFrame extends JFrame implements ActionListener
public CheckBoxFrame()
setTitle("CheckBoxTest");
setSize(300,200);
addWindowListener(new WindowAdapter()
public void windowClosing(WindowEvent e)
System.exit(0);
);
JPanel p=new JPanel();
bold=addCheckBox(p,"Bold");
italic=addCheckBox(p,"Italic");
getContentPane().add(p,"South");
panel=new CheckBoxTestPanel();
getContentPane().add(panel,"Center");
public JCheckBox addCheckBox(JPanel p,String name)
JCheckBox c=new JCheckBox(name);
c.addActionListener( );
p.add(c);
return c;
public void______
int m=(bold.isSelected()Font.BOLD:0)+(italic.isSelected()Font.ITALIC:0);
panel.setFont(m);
private CheckBoxTestPanel panel;
private JCheckBox bold;
private JCheckBox italic;
class CheckBoxTestPanel extends JPanel
public CheckBoxTestPanel()
setFont(Font.PLAIN);
public void setFont(int m)
setFont(new Font("SansSerif",m,12));
repaint();
public void paintComponent(Graphics g)
super.paintComponent(g);
g.drawstring("The quick brown fox jumps over the lazy dog.",0,50);

public class java2
public static void main(String[]args)
JFrame frame=new CheckBoxFrame();
frame.show();